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{{ClinPsy}}
  
{{ClinPsy}}
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{{Infobox Disease
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'''Rumination''' is an [[eating disorder]] characterized by having the contents of the [[stomach]] drawn back up into the [[mouth]], chewed for a second time, and [[swallowing|swallowed]] again.
  
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| Name = Rumination syndrome
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| Image = Rumination_manometry.jpg
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| Width = 243px
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| Caption = A [[:wikt:postprandial|postprandial]] [[manometry]] of a patient with rumination syndrome showing intra-abdominal pressure. The "spikes" are characteristic of the abdominal wall contractions responsible for the regurgitation in rumination.
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| alt = A line graph. The line has pronounced upwards spikes followed by less pronounced downward spikes. These spikes are separated by longer intermittent periods where the line is jagged, but roughly and statistically straight.
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| DiseasesDB = 34255
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| ICD10 = {{ICD10|P|92|1|p|90}}, {{ICD10|F|98|2|f|90}} |
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| ICD9 = {{ICD9|307.53}}
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| ICDO =
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| OMIM =
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| MedlinePlus = 001539
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| eMedicineSubj = article
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| eMedicineTopic = 916297
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| MeshID = D019959
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}}
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'''Rumination syndrome''', or '''Merycism''' is an under-diagnosed [[Chronic (medicine)|chronic]] [[eating disorder]],<!-- Seperation for a clean list of primary sources (sources agree on this first point and can be listed here conveniently)
   
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This is an ideal summary of rumination and cites many published sources. It is available on the journal's site for free
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In some animals, known as [[ruminant]]s, this is a natural and healthy part of [[digestion]] and is not considered an eating disorder. However, in other species (including humans), such behavior is atypical and potentially dangerous as the [[esophagus]] can be damaged by frequent exposure to [[stomach]] acids.
  
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--><ref name="pgradreview">{{citation
   
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| last1 = Papadopoulos | first1 = Vassilios
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Rumination is also associated with eating disorders such as anorexia nervosa, and can be the result of ones apprehension and nervousness after eating a normal meal. For those with purging behaviors, rumination can take place when the option of getting rid of a meal via throwing up is not available (thus, one might feel worried and visibly upset)
  
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| last2 = Mimidis | first2 = Konstantinos
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| title = The rumination syndrome in adults: A review of the pathophysiology, diagnosis and treatment
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| year = 2007
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| month = July-September
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| volume = 53
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| issue = 3
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| pages = 203&ndash;206
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| journal = Journal of Postgraduate Medicine
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| pmid = 17699999
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| doi = 10.4103/0022-3859.33868
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}}</ref><!--
   
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This reference sets out the criteria and characterizations of rumination syndrome in adolescents (As it was previously defined only in infants and the mentally/physically handicapped), in particular the signs and symptoms, causes, demographics, diagnostic criteria, and patient outcomes.
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--><ref name="nosology">{{citation
   
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| last1 = Chial | first1 = Heather J
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==Assessment==
  
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| last2 = Camilleri | first2 = Michael
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| last3 = Williams | first3 = Donald E
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| last4 = Litzinger | first4 = Kristi
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| last5 = Perrault | first5 = Jean
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| title = Rumination syndrome in children and adolescents: diagnosis, treatment, and prognosis
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| year = 2003
  +
| volume = 111
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| issue = 1
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| pages = 158&ndash;162
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| journal = Pediatrics
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| pmid = 12509570
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| url = http://pediatrics.aappublications.org/cgi/reprint/111/1/158
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| doi = 10.1542/peds.111.1.158
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}}</ref><!--
   
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ARTICLE CONTINUES HERE
   
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--> characterized by effortless [[regurgitation (digestion)|regurgitation]] of most meals following consumption. There is no [[retching]], [[nausea]], [[heartburn]], odours, or abdominal pains associated with the regurgitation, as there is with typical [[vomiting]]. The disorder has been historically documented as affecting only [[pediatrics|infant]]s, [[pediatrics|young children]], and people with [[Developmental disability|cognitive disabilities]] (where the prevalence is as high as 10% in institutionalized patients with various mental disabilities).
−
==Treatment==
  
  +
Today it is being diagnosed in increasing numbers of otherwise healthy adolescents and adults, though there is a lack of awareness of the condition by doctors, patients and the general public.
   
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Rumination syndrome presents itself in a variety of ways, especially when comparing an adult without a mental disability to an infant or to a mentally impaired individual. Like most eating disorders, rumination can adversely affect normal functioning and the social lives of individuals. It has been linked with depression.
   
  +
There is little comprehensive data regarding rumination syndrome in otherwise healthy individuals.
  +
Most people with the disorder are private about their illness, and are often misdiagnosed due to the number of symptoms, and the clinical similarities between rumination syndrome and other disorders of the stomach and esophogus, such as [[gastroparesis]] and [[bulimia nervosa]]. These include the acid-induced erosion of the [[esophagus]] and teeth (causing dental decay), [[halitosis]], [[malnutrition]], severe [[weight loss]] and an unquenchable appetite. Individuals may begin regurgitating within a minute following ingestion, and the full cycle of ingestion and regurgitation can mimic the [[binging and purging]] of bulimia.
  +
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Diagnosis of rumination syndrome is non-invasive, and based on a history of the individual. Treatment is promising, with upwards of 85% of individuals responding positively to treatment, including infants and the mentally handicapped.
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== Classification ==
  +
Rumination syndrome is classified as a functional eating disorder of the [[stomach]] and [[esophagus]], or a functional gastroduodenal disorder.<ref name="tacketal" /> It is grouped alongside other eating disorders such as bulimia and [[pica]],<ref name="icd10f" /><ref name="icd10p" /> which are themselves grouped under non-psychotic mental disorder.
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== Signs and symptoms ==
  +
  +
While the number and severity of symptoms varies among individuals, repetitive regurgitation of undigested food (known as rumination) after the start of a meal is always present.<ref name="pgradreview" /><ref name="nosology" /> In some individuals, the regurgitation is small, occurring over a long period of time following ingestion, and can be rechewed and swallowed. In others, the amount can be bilious and short lasting, and must be expelled.
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While some only experience symptoms following some meals, most experience episodes following any ingestion, from a single bite to a massive feast.<ref name="mayosymptoms">{{citation
  +
  +
| last1 = Camilleri | first1 = Michael
  +
| last2 = Seime | first2 = Richard J
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| title = Rumination Syndrome, symptoms
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| publisher = Mayo Clinic
  +
| location = Rochester, Minnesota
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| url =http://www.mayoclinic.org/rumination-syndrome/symptoms.html
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| accessdate = 2009-06-26}}
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</ref> However, some long-term patients will find a select couple of food or drink items that do not trigger a response.
  +
  +
Unlike typical vomiting, the regurgitation is typically described as effortless and unforced.<ref name="pgradreview" /> There is seldom nausea preceding the expulsion, and the undigested food lacks the bitter taste and odour of [[stomach acid]] and [[bile]].<ref name="pgradreview" />
  +
  +
Symptoms can begin to manifest at any point from the ingestion of the meal to 120&nbsp;minutes thereafter.<ref name="nosology" /> However, the more common range is between 30&nbsp;seconds to 1&nbsp;hour after the completion of a meal.<ref name="mayosymptoms" /> Symptoms tend to cease when the ruminated contents become acidic.<ref name="pgradreview" /><ref name="mayosymptoms" />
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Abdominal pain&nbsp;(38.1%), lack of fecal production or [[constipation]]&nbsp;(21.1%), nausea&nbsp;(17.0%), [[diarrhea]]&nbsp;(8.2%), bloating&nbsp;(4.1%), and dental decay&nbsp;(3.4%) are also described as common symptoms in day-to-day life.<ref name="nosology" /> These symptoms are not necessarily prevalent during regurgitation episodes, and can happen at any time. Weight loss is often observed (42.2%) at an average loss of 9.6&nbsp;kilograms, and is more common in cases where the disorder has gone undiagnosed for a longer period of time,<ref name="nosology" /> though this may be expected of the nutrition deficiencies that often accompany the disorder as a consequence of its symptoms.<ref name="nosology" /> Depression has also been linked with rumination syndrome,<ref>{{citation
  +
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| last1 = Amarnath | first1 = Rathna P
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| last2 = Abell | first2 = Thomas L
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| last5 = Malagelada | first5 = Juan-R
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| title = The rumination syndrome in adults. A characteristic manometric pattern.
  +
| year = 1986
  +
| month = October
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| volume = 105
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| issue = 4
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| pages = 513&ndash;518
  +
| journal = Annals of Internal Medicine
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| pmid = 3752757
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| url = http://www.annals.org/cgi/content/abstract/105/4/513
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| doi = 10.1059/0003-4819-105-4-513
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| doi_brokendate = 2009-09-30
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}}</ref> though its{{Clarify|date=October 2009}} effects on the disorder are unknown.<ref name="pgradreview" />
  +
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== Causes ==
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The cause of rumination syndrome is unknown. However, studies have drawn a correlation between hypothesized causes and the history of patients with the disorder. In infants and the cognitively impaired, the disease has normally been attributed to over-stimulation and under-stimulation from parents and caregivers, causing the individual to seek self-gratification and self-stimulus due to the lack or abundance of external stimuli. The disorder has also commonly been attributed to a bout of illness, a period of stress in the individual's recent past, and to changes in medication.<ref name="pgradreview" />
  +
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In adults and adolescents, hypothesized causes generally fall into one of either category: habit-induced, and trauma-induced. Habit-induced individuals generally have a past history of bulimia nervosa or of intentional regurgitation (magicians and professional regurgitators, for example), which though initially self-induced, forms a subconscious habit that can continue to manifest itself outside the control of the affected individual. Trauma-induced individuals describe an emotional or physical injury (such as recent surgery, psychological distress, concussions, deaths in the family, etc.), which preceded the onset of rumination, often by several months.<ref name="pgradreview" /><ref name="nosology" />
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== Diagnosis ==
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Rumination syndrome is diagnosed based on a complete history of the individual. Costly and invasive studies such as gastroduodenal manometry and esophageal PH testing are unnecessary and will often aid in misdiagnosis.<ref name="pgradreview" /> Based on typical observed features, several criteria have been suggested for diagnosing rumination syndrome.<ref name="nosology" /> The primary symptom, the regurgitation of recently ingested food, must be consistent, occurring for at least six&nbsp;weeks of the past twelve months. The regurgitation must begin within thirty&nbsp;minutes of the completion of a meal. Patients may either chew the regurgitated matter or expel it. The symptoms must stop within ninety&nbsp;minutes, or when the regurgitated matter becomes acidic. The symptoms must not be the result of a mechanical obstruction, and should not respond to the standard treatment for [[gastroesophageal reflux disease]].
  +
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In adults, the diagnosis is supported by the absence of classical or structural diseases of the gastrointestinal system. Supportive criteria include regurgitant that is not sour or acidic tasting,<ref name="emed" /> is generally odourless, is effortless,<ref name="mayosymptoms" /> or at most preceded by a belching sensation,<ref name="pgradreview" /> that there is no retching preceding the regurgitation,<ref name="pgradreview" /> and that the act is not associated with nausea or heartburn.<ref name="pgradreview" />
  +
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Patients visit an average of five physicians over 2.75 years before reaching being correctly diagnosed with rumination syndrome.<ref name="bulimia">{{citation
  +
  +
| last1 = LaRocca | first1 = Felix E
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| last2 = Della-Fera | first2 = Mary-Anne
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| title = Rumination: Its significance in adults with bulimia nervosa
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| year = 1986
  +
| month = October
  +
| volume = 27
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| issue = 3
  +
| pages = 209&ndash;212
  +
| journal = Psychosomatics
  +
| pmid = 3457391
  +
}}</ref>
  +
  +
=== Differential diagnosis ===
  +
Rumination syndrome in adults is a complicated disorder whose symptoms can mimic those of several other gastroesophogeal disorders and diseases. bulimia nervosa and gastroparesis are especially prevalent among the misdiagnoses of rumination.<ref name="pgradreview" />
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[[Bulimia nervosa]], among adults and especially adolescents, is by far the most common misdiagnosis patients will hear during their experiences with rumination syndrome. This is due to the similarities in symptoms to an outside observer - "vomiting" (purging) following food intake (binging) - which in long-term patients may include ingesting copious amounts to offset malnutrition (followed by a hasty retreat to the washroom), and a lack of willingness to expose their condition and its symptoms. While it has been suggested that there is a connection between rumination and bulimia,<ref name="bulimia" /><ref name="obrien">{{citation
  +
  +
| last1 = O'Brien | first1 = Michael D
  +
| last2 = Bruce | first2 = Barbara K
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| last3 = Camilleri | first3 = Michael
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| title = The rumination syndrome: Clinical features rather than manometric diagnosis
  +
| year = 1995
  +
| month = March
  +
| volume = 108
  +
| issue = 4
  +
| pages = 1024&ndash;1029
  +
| journal = Gastroenterology
  +
| pmid = 7698568
  +
| doi = 10.1016/0016-5085(95)90199-X
  +
}}</ref> unlike bulimia, rumination is not self-inflicted. Adult and adolescents with rumination syndrome are generally well aware of their gradually increasing malnutrition, but are unable to control the reflex. In contrast, those with bulimia intentionally induce vomiting, and seldom re-swallow food.<ref name="pgradreview" />
  +
  +
[[Gastroparesis]] is another common misdiagnosis.<ref name="pgradreview" /> Like rumination syndrome, patients with gastroparesis often bring up food following the ingestion of a meal. Unlike rumination, gastroparesis causes [[vomiting]] (in contrast to [[regurgitation (digestion)|regurgitation]]) of food, which is not being digested further, from the stomach . This vomiting occurs several hours after a meal is ingested, is preceded by nausea and retching, and has the bitter or sour taste typical of vomit.<ref name="mayosymptoms" />
  +
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== Pathophysiology ==
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Rumination syndrome is a poorly understood disorder, and a number of theories have speculated the mechanisms that cause the regurgitation,<ref name="nosology" /> which is a unique symptom to this disorder. While no theory has gained a consensus, some are more notable and widely published than others.<ref name="pgradreview" />
  +
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The most widely documented mechanism is that the ingestion of food causes [[stomach|gastric]] distention (stretching), which is followed by abdominal compression and the simultaneous relaxation of the [[Lower esophageal sphincter]] (LES). This creates a common cavity between the stomach and the [[oropharynx]] that allows the partially digested material to return to the mouth. There are several offered explanations for the sudden relaxation of the LES.<ref name="emed">
  +
{{citation
  +
  +
| last1 = Ellis | first1 = Cynthia R
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| last2 = Schnoes | first2 = Connie J
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| title = Eating Disorder, Rumination
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| year = 2009
  +
| journal = Medscape Pediatrics
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| url = http://emedicine.medscape.com/article/916297-overview
  +
| accessdate = 2009-09-07
  +
}}</ref> Among these explanations is that it is a learned voluntary relaxation, which is common in those with or having had bulimia. While this relaxation may be voluntary, the overall process of rumination is still generally involuntary. Relaxation due to intra-abdominal pressure is another proposed explanation, which would make abdominal compression the primary mechanism. The third is an adaptation of the belch reflex, which is the most commonly described mechanism. The swallowing of air immediately prior to regurgitation causes the activation of the belching reflex that triggers the relaxation of the LES. Patients often describe a feeling similar to the onset of a belch preceding rumination.<ref name="pgradreview" />
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== Treatment and prognosis ==
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There is presently no known cure for rumination. [[Proton pump inhibitors]] and other medications have been used to little or no effect.<ref name="breathingtech">{{citation
  +
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| last1 = Chitkara | first = Denesh K
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| last2 = van Tilburg | first2 = Miranda
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| last3 = Whitehead | first3 = William E
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| last4 = Talley | first4 = Nicholas
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| title = Teaching diaphragmatic breathing for rumination syndrome
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| year = 2006
  +
| volume = 101
  +
| issue = 11
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| pages = 2449&ndash;2452
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| journal = Gastroenterology
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| pmid = 17090274
  +
}}</ref>
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Treatment is different for infants and the mentally handicapped than for adults and adolescents of normal intelligence.
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Among the former two, behavioral and mild aversive training has shown to cause improvement in most cases.<ref name="aversive" /> Aversive training involves associating the ruminating behavior with negative results, and rewarding good behavior and eating. Placing a sour or bitter taste on the tongue when the individual begins the movements or breathing patterns typical of his or her ruminating behavior is the generally accepted method for aversive training,<ref name="aversive">{{citation
  +
  +
| last1 = Wagaman | first1 = JR
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| last2 = Williams | first2 = DE
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| last3 = Camilleri | first3 = M
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| title = Behavioral intervention for the treatment of rumination
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| year = 1998
  +
| volume = 27
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| pages = 596&ndash;598
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| journal = Pediatric Gastroenterology and Nutrition
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| pmid = 9822330
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| doi = 10.1097/00005176-199811000-00019
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| issue = 5
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}}</ref>
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although some older studies advocate the use of pinching.{{Citation needed|date=September 2009}}
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In patients of normal intelligence, rumination is not an intentional behavior and is habitually reversed using diaphragmatic breathing to counter the urge to regurgitate.<ref name="breathingtech" /> Alongside reassurance, explanation and habit reversal, patients are shown how to breathe using their [[Thoracic diaphragm|diaphragms]] prior to and during the normal rumination period.<ref name="breathingtech" /><ref>{{citation
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| last1 = Johnson | first1 = WG
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| last2 = Corrigan | first2 = SA
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| last3 = Crusco | first3 = AH
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| last4 = Jarell | first4 = MP
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| title = Behavioral assessment and treatment of postprandial regurgitation
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| year = 1987
  +
| volume = 9
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| issue = 6
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| pages = 679&ndash;684
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| journal = Gastroenterology
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| pmid = 3443732
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}}</ref> A similar breathing pattern can be used to prevent normal vomiting. Breathing in this method works by physically preventing the abdominal contractions required to expel stomach contents.
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Supportive therapy and diaphragmatic breathing has shown to cause improvement in 56% of cases, and total cessation of symptoms in an additional 30% in one study of 54 adolescent patients who were followed up 10 months after initial treatments.<ref name="nosology" /> Patients who successfully use the technique often notice an immediate change in health for the better.<ref name="breathingtech" /> Individuals who have had bulimia or who intentionally induced vomiting in the past have a reduced chance for improvement due to the reinforced behavior.<ref name="bulimia" /><ref name="breathingtech" /> The technique is not used with infants or young children due to the complex timing and concentration required for it to be successful. Most infants grow out of the disorder within a year or with aversive training.<ref name="ininfants" />
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== Epidemiology ==
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[[Image:Rumination distribution by age.png|thumb|180px|alt=A chart visualizing the distribution of patients (by age) at the diagnosis of rumination syndrome. It is a bar graph, representing ages between newborn and 20. No patients under 5 were used. The graph peaks in the 14 to 18 years range, with the most patients being diagnosed at 17 (20 of the 145 patients). Moving away from 17 years of age, the number of patients diagnosed tapers off gradually.|Age distribution at diagnosis.<ref name="nosology" />]]
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Rumination disorder was initially documented<ref name="ininfants">{{citation
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  +
| last1 = Rasquin-Weber | first = A
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| last2 = Hyman | first2 = PE
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| last3 = Cucchiara | first3 = S
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| title = Childhood functional gastrointestinal disorders
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| year = 1999
  +
| volume = 45 (Supplement 2)
  +
| pages = 1160&ndash;1168
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| journal = Gut
  +
| pmid = 10457047
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| last4 = Fleisher
  +
| last5 = Hyams
  +
| last6 = Milla
  +
| last7 = Staiano
  +
}}</ref><ref name="hcchildren">{{citation
  +
  +
| last = Sullivan | first = PB
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| title = Gastrointestinal problems in the neurologically impaired child
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| year = 1997
  +
| volume = 11
  +
| issue = 3
  +
| pages = 529&ndash;546
  +
| journal = Baillieres Clinical Gastroenterology
  +
| pmid = 9448914
  +
| doi = 10.1016/S0950-3528(97)90030-0
  +
}}</ref>
  +
as affecting newborns,<ref name="icd10p">{{citation
  +
  +
| title = ICD-10 entries for rumination syndrome - P92.1
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| url = http://apps.who.int/classifications/apps/icd/icd10online/?gp90.htm+p921
  +
| accessdate = 2009-08-10
  +
}}</ref>
  +
infants, children<ref name="icd10f">{{citation
  +
  +
| title = ICD-10 entries for rumination syndrome - F98.2
  +
| url = http://apps.who.int/classifications/apps/icd/icd10online/?gf90.htm+f982
  +
| accessdate = 2009-08-10
  +
}}</ref>
  +
and individuals with mental and functional disabilities (the cognitively handicapped).<ref name="hcchildren" /><ref name="handicapped">{{citation
  +
  +
| last1 = Rogers | first = B
  +
| last2 = Stratton | first2 = P
  +
| last3 = Victor | first3 = J
  +
| last4 = Cennedy | first4 = B
  +
| last5 = Andres | first5 = M
  +
| title = Chronic regurgitation among persons with mental retardation: A need for combined medical and interdisciplinary strategies
  +
| year = 1992
  +
| volume = 96
  +
| issue = 5
  +
| pages = 522&ndash;527
  +
| journal = American Journal of Mental Retardation
  +
| pmid = 1562309
  +
}}</ref>
  +
It has since been recognized to occur in both males and females of all ages and cognitive abilities.<ref name="pgradreview" /><ref name="kolden" />
  +
  +
Among the latter, it is described with almost equal prevalence among infants (6&ndash;10% of the population) and institutionalized adults (8&ndash;10%).<ref name="pgradreview" />
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In infants, it typically occurs within the first 3&ndash;12 months of age.<ref name="<ref name="ininfants" />
  +
  +
The occurrence of rumination syndrome within the general population has not been defined.<ref name="tacketal" /> Rumination is sometimes described as rare<ref name="pgradreview" />, but has also been described as not rare, but rather rarely recognized.<ref name="foxetal" />
  +
The disorder has a female predominance.<ref name="tacketal">{{citation
  +
  +
| last = Tack | first1 = Jan
  +
| last2 = Talley | first2 = Nicholas J
  +
| last3 = Camilleri | first3 = Michael
  +
| last4 = Holtmann | first4 = Gerald
  +
| last5 = Hu | first5 = Pinjin
  +
| last6 = Malagelada | first6 = Juan-R
  +
| last7 = Stanghellini | first7 = Vincenzo
  +
| title = Functional gastroduodenal disorders
  +
| year = 2006
  +
| volume = 130
  +
| issue = 5
  +
| pages = 1466&ndash;1479
  +
| journal = Gastroenterology
  +
| pmid = 16678560
  +
| doi = 10.1053/j.gastro.2005.11.059
  +
| url = http://www.romecriteria.org/pdfs/p1466FunctionalGastroduodenal1.pdf
  +
}}</ref> The typical age of adolescent onset is 12.9, give or take 0.4 years (±), with males affected sooner than females (11.0 ± 0.8 for males versus 13.8 ± 0.5 for females).<ref name="nosology" />
  +
  +
There is little evidence concerning the impact of hereditary influence in rumination syndrome.<ref name="emed" /> However, case reports involving entire families with rumination exist.<ref name="historiccases" />
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  +
== History ==
  +
The term ''Rumination'' is derived from the Latin word "''ruminare''", which means ''to chew the cud''.<ref name="historiccases" /> First described in ancient times, and mentioned in the writings of Aristotle, rumination syndrome was clinically documented in 1618 by Italian anatomist [[Hieronymus Fabricius|Fabricus ab Aquapendende]], who wrote of the symptoms in a patient of his.<ref name="kolden">{{citation
  +
  +
| last = Olden
  +
| first = Kevin W
  +
| title = Rumination
  +
| year = 2001
  +
| volume = 4
  +
| issue = 4
  +
| pages = 351&ndash;358
  +
| journal = Current Treatment Options in Gastroenterology
  +
| pmid = 11469994
  +
| url = http://resources.metapress.com/pdf-preview.axd?code=08222k1110283n0m&size=largest
  +
| doi = 10.1007/s11938-001-0061-z
  +
}}</ref><ref name="historiccases">{{citation
  +
  +
| last = Brockbank | first = EM
  +
| title = Merycism or rumination in man
  +
| year = 1907
  +
| volume = 1
  +
| issue = 2408
  +
| pages = 421&ndash;427
  +
| journal = British Medical Journal
  +
| pmc = 2356806
  +
| doi = 10.1136/bmj.1.2408.421
  +
}}</ref>
  +
  +
Among the earliest cases of rumination was that of a physician in the nineteenth century, [[Charles-Édouard Brown-Séquard]], who acquired the condition as the result of experiments upon himself. As a way of evaluating and testing the acid response of the stomach to various foods, the doctor would swallow sponges tied to a string, then intentionally regurgitate them to analyze the contents. As a result of these experiments, the doctor eventually regurgitated his meals habitually by reflex.<ref>{{citation
  +
  +
| last = Kanner | first = L
  +
| title = Historical notes on rumination in man
  +
| year = 1936
  +
| month = February
  +
| volume = 43
  +
| issue = 2
  +
| pages = 27&ndash;60
  +
| journal = Medical Life
  +
| oclc = 11295688
  +
}}</ref>
  +
  +
Numerous case reports exist from before the twentieth century, but were influenced greatly by the methods and thinking used in that time. By the early twentieth century, it was becoming increasingly evident that rumination presented itself in a variety of ways in response to a variety of conditions.<ref name="kolden" /> Although still considered a disorder of infancy and cognitive disability at that time, the difference in presentation between infants and adults was well established.<ref name="historiccases" />
  +
  +
Studies of rumination in otherwise healthy adults became decreasingly rare starting in the 1900s, and the majority of published reports analyzing the syndrome in mentally healthy patients appeared thereafter. At first, adult rumination was described and treated as a benign condition. It is now described as otherwise.<ref>{{citation
  +
  +
| last = Sidhu | first = Shawn S
  +
| last2 = Rick | first2 = James R
  +
| title = Erosive eosinophilic esophagitis in rumination syndrome
  +
| year = 2009
  +
| volume = 22
  +
| issue = 1
  +
| article = 2
  +
| journal = Jefferson Journal of Psychiatry
  +
| issn =1935-0783
  +
| url = http://jdc.jefferson.edu/cgi/viewcontent.cgi?article=1028&context=jeffjpsychiatry
  +
}}</ref> While the base of patients to examine has gradually increased as more and more people come forward with their symptoms, awareness of the condition by the medical community and the general public is still limited.<ref name="pgradreview" /><ref name="foxetal">{{citation
  +
  +
| last1 = Fox | first1 = Mark
  +
| last2 = Young | first2 = Alasdair
  +
| last3 = Anggiansah | first3 = Roy
  +
| last4 = Anggiansah | first4 = Angela
  +
| last5 = Sanderson | first5 = Jeremy
  +
| title = A 22 year old man with persistent regurgitation and vomiting: case outcome
  +
| year = 2006
  +
| volume = 333
  +
| issue = 7559
  +
| page = 133
  +
| journal = British Medical Journal
  +
| pmid = 16840471
  +
| url = http://www.labmeeting.com/paper/8505339/fox-2006-a-22-year-old-man-with-persistent-regurgitation-and-vomiting-case-outcome
  +
| doi = 10.1136/bmj.333.7559.133
  +
}}
  +
</ref><ref>{{citation
  +
  +
| last1 = Camilleri | first1 = Michael
  +
| last2 = Seime | first2 = Richard J
  +
| title = Rumination Syndrome, an overview
  +
| publisher = Mayo Clinic
  +
| location = Rochester, Minnesota
  +
| url = http://www.mayoclinic.org/rumination-syndrome/
  +
| accessdate = 2009-06-26
  +
}}</ref><ref>{{citation
  +
  +
| last = Parry-Jones
  +
| first = B
  +
| title = Merycism or rumination disorder. A historical investigation and current assessment
  +
| year = 1994
  +
| volume = 165
  +
| pages = 303&ndash;314
  +
| journal = British Journal of Psychiatry
  +
| pmid = 7994499
  +
| doi = 10.1192/bjp.165.3.303
  +
| issue = 3
  +
}}</ref>
  +
  +
== In other animals ==
  +
  +
The chewing of cud by animals such as cows, goats, and giraffes is considered normal behavior. These animals are known as [[ruminants]].<ref name="emed" /> Such behavior, though termed rumination, is not related to human rumination syndrome, but is ordinary behavior nonetheless. Involuntary rumination, similar to what is seen in humans, has been described in [[gorilla]]s and other [[primate]]s.<ref name="ingorillas">{{citation
  +
  +
| last = Hill | first = SP
  +
| title = Do gorillas regurgitate potentially-injurious stomach acid during 'regurgitation and reingestion?'
  +
| year = 2009
  +
| month = May
  +
| volume = 18
  +
| issue = 2
  +
| pages = 123&ndash;127
  +
| journal = Animal Welfare
  +
| issn = 0962-7286
  +
| url = http://openurl.ingenta.com/content?genre=article&issn=0962-7286&volume=18&issue=2&spage=123&epage=127
  +
}}</ref>
   
 
==See also==
  
==See also==
Line 19: Line 412:
   
   
  +
==References==
  +
{{reflist|2}}
   
  +
==External links==
  +
* [http://www.mayoclinic.org/rumination-syndrome/ MayoClinic.org Pediatrics - Rumination Syndrome] - The Mayo Clinic website provides a clear and concise overview of the disorder.
  +
* [http://my.webmd.com/content/article/60/67120.htm WedMD - Rumination disorder] - Web MD. Provides an general overview of the disease.
   
  +
{{Mental and behavioral disorders}}
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[[Category:Diseases]]
  
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{{Certain conditions originating in the perinatal period}}
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{{DEFAULTSORT:Rumination Syndrome}}
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[[Category:Mental disorders]]
 
[[Category:Eating disorders]]
  
[[Category:Eating disorders]]
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[[de:Essstörung]]
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{{enWP|Rumination syndrome}}

Revision as of 16:25, 16 January 2010

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Rumination_manometry.jpg|
Rumination syndrome
ICD-10 P921, F982
ICD-9 307.53
OMIM [1]
DiseasesDB 34255
MedlinePlus 001539
eMedicine article/916297
MeSH {{{MeshNumber}}}

Rumination syndrome, or Merycism is an under-diagnosed chronic eating disorder,[1][2] characterized by effortless regurgitation of most meals following consumption. There is no retching, nausea, heartburn, odours, or abdominal pains associated with the regurgitation, as there is with typical vomiting. The disorder has been historically documented as affecting only infants, young children, and people with cognitive disabilities (where the prevalence is as high as 10% in institutionalized patients with various mental disabilities). Today it is being diagnosed in increasing numbers of otherwise healthy adolescents and adults, though there is a lack of awareness of the condition by doctors, patients and the general public.

Rumination syndrome presents itself in a variety of ways, especially when comparing an adult without a mental disability to an infant or to a mentally impaired individual. Like most eating disorders, rumination can adversely affect normal functioning and the social lives of individuals. It has been linked with depression.

There is little comprehensive data regarding rumination syndrome in otherwise healthy individuals. Most people with the disorder are private about their illness, and are often misdiagnosed due to the number of symptoms, and the clinical similarities between rumination syndrome and other disorders of the stomach and esophogus, such as gastroparesis and bulimia nervosa. These include the acid-induced erosion of the esophagus and teeth (causing dental decay), halitosis, malnutrition, severe weight loss and an unquenchable appetite. Individuals may begin regurgitating within a minute following ingestion, and the full cycle of ingestion and regurgitation can mimic the binging and purging of bulimia.

Diagnosis of rumination syndrome is non-invasive, and based on a history of the individual. Treatment is promising, with upwards of 85% of individuals responding positively to treatment, including infants and the mentally handicapped.

Classification

Rumination syndrome is classified as a functional eating disorder of the stomach and esophagus, or a functional gastroduodenal disorder.[3] It is grouped alongside other eating disorders such as bulimia and pica,[4][5] which are themselves grouped under non-psychotic mental disorder.

Signs and symptoms

While the number and severity of symptoms varies among individuals, repetitive regurgitation of undigested food (known as rumination) after the start of a meal is always present.[1][2] In some individuals, the regurgitation is small, occurring over a long period of time following ingestion, and can be rechewed and swallowed. In others, the amount can be bilious and short lasting, and must be expelled. While some only experience symptoms following some meals, most experience episodes following any ingestion, from a single bite to a massive feast.[6] However, some long-term patients will find a select couple of food or drink items that do not trigger a response.

Unlike typical vomiting, the regurgitation is typically described as effortless and unforced.[1] There is seldom nausea preceding the expulsion, and the undigested food lacks the bitter taste and odour of stomach acid and bile.[1]

Symptoms can begin to manifest at any point from the ingestion of the meal to 120 minutes thereafter.[2] However, the more common range is between 30 seconds to 1 hour after the completion of a meal.[6] Symptoms tend to cease when the ruminated contents become acidic.[1][6]

Abdominal pain (38.1%), lack of fecal production or constipation (21.1%), nausea (17.0%), diarrhea (8.2%), bloating (4.1%), and dental decay (3.4%) are also described as common symptoms in day-to-day life.[2] These symptoms are not necessarily prevalent during regurgitation episodes, and can happen at any time. Weight loss is often observed (42.2%) at an average loss of 9.6 kilograms, and is more common in cases where the disorder has gone undiagnosed for a longer period of time,[2] though this may be expected of the nutrition deficiencies that often accompany the disorder as a consequence of its symptoms.[2] Depression has also been linked with rumination syndrome,[7] though its

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effects on the disorder are unknown.[1]

Causes

The cause of rumination syndrome is unknown. However, studies have drawn a correlation between hypothesized causes and the history of patients with the disorder. In infants and the cognitively impaired, the disease has normally been attributed to over-stimulation and under-stimulation from parents and caregivers, causing the individual to seek self-gratification and self-stimulus due to the lack or abundance of external stimuli. The disorder has also commonly been attributed to a bout of illness, a period of stress in the individual's recent past, and to changes in medication.[1]

In adults and adolescents, hypothesized causes generally fall into one of either category: habit-induced, and trauma-induced. Habit-induced individuals generally have a past history of bulimia nervosa or of intentional regurgitation (magicians and professional regurgitators, for example), which though initially self-induced, forms a subconscious habit that can continue to manifest itself outside the control of the affected individual. Trauma-induced individuals describe an emotional or physical injury (such as recent surgery, psychological distress, concussions, deaths in the family, etc.), which preceded the onset of rumination, often by several months.[1][2]

Diagnosis

Rumination syndrome is diagnosed based on a complete history of the individual. Costly and invasive studies such as gastroduodenal manometry and esophageal PH testing are unnecessary and will often aid in misdiagnosis.[1] Based on typical observed features, several criteria have been suggested for diagnosing rumination syndrome.[2] The primary symptom, the regurgitation of recently ingested food, must be consistent, occurring for at least six weeks of the past twelve months. The regurgitation must begin within thirty minutes of the completion of a meal. Patients may either chew the regurgitated matter or expel it. The symptoms must stop within ninety minutes, or when the regurgitated matter becomes acidic. The symptoms must not be the result of a mechanical obstruction, and should not respond to the standard treatment for gastroesophageal reflux disease.

In adults, the diagnosis is supported by the absence of classical or structural diseases of the gastrointestinal system. Supportive criteria include regurgitant that is not sour or acidic tasting,[8] is generally odourless, is effortless,[6] or at most preceded by a belching sensation,[1] that there is no retching preceding the regurgitation,[1] and that the act is not associated with nausea or heartburn.[1]

Patients visit an average of five physicians over 2.75 years before reaching being correctly diagnosed with rumination syndrome.[9]

Differential diagnosis

Rumination syndrome in adults is a complicated disorder whose symptoms can mimic those of several other gastroesophogeal disorders and diseases. bulimia nervosa and gastroparesis are especially prevalent among the misdiagnoses of rumination.[1]

Bulimia nervosa, among adults and especially adolescents, is by far the most common misdiagnosis patients will hear during their experiences with rumination syndrome. This is due to the similarities in symptoms to an outside observer - "vomiting" (purging) following food intake (binging) - which in long-term patients may include ingesting copious amounts to offset malnutrition (followed by a hasty retreat to the washroom), and a lack of willingness to expose their condition and its symptoms. While it has been suggested that there is a connection between rumination and bulimia,[9][10] unlike bulimia, rumination is not self-inflicted. Adult and adolescents with rumination syndrome are generally well aware of their gradually increasing malnutrition, but are unable to control the reflex. In contrast, those with bulimia intentionally induce vomiting, and seldom re-swallow food.[1]

Gastroparesis is another common misdiagnosis.[1] Like rumination syndrome, patients with gastroparesis often bring up food following the ingestion of a meal. Unlike rumination, gastroparesis causes vomiting (in contrast to regurgitation) of food, which is not being digested further, from the stomach . This vomiting occurs several hours after a meal is ingested, is preceded by nausea and retching, and has the bitter or sour taste typical of vomit.[6]

Pathophysiology

Rumination syndrome is a poorly understood disorder, and a number of theories have speculated the mechanisms that cause the regurgitation,[2] which is a unique symptom to this disorder. While no theory has gained a consensus, some are more notable and widely published than others.[1]

The most widely documented mechanism is that the ingestion of food causes gastric distention (stretching), which is followed by abdominal compression and the simultaneous relaxation of the Lower esophageal sphincter (LES). This creates a common cavity between the stomach and the oropharynx that allows the partially digested material to return to the mouth. There are several offered explanations for the sudden relaxation of the LES.[8] Among these explanations is that it is a learned voluntary relaxation, which is common in those with or having had bulimia. While this relaxation may be voluntary, the overall process of rumination is still generally involuntary. Relaxation due to intra-abdominal pressure is another proposed explanation, which would make abdominal compression the primary mechanism. The third is an adaptation of the belch reflex, which is the most commonly described mechanism. The swallowing of air immediately prior to regurgitation causes the activation of the belching reflex that triggers the relaxation of the LES. Patients often describe a feeling similar to the onset of a belch preceding rumination.[1]

Treatment and prognosis

There is presently no known cure for rumination. Proton pump inhibitors and other medications have been used to little or no effect.[11] Treatment is different for infants and the mentally handicapped than for adults and adolescents of normal intelligence. Among the former two, behavioral and mild aversive training has shown to cause improvement in most cases.[12] Aversive training involves associating the ruminating behavior with negative results, and rewarding good behavior and eating. Placing a sour or bitter taste on the tongue when the individual begins the movements or breathing patterns typical of his or her ruminating behavior is the generally accepted method for aversive training,[12] although some older studies advocate the use of pinching.[citation needed] In patients of normal intelligence, rumination is not an intentional behavior and is habitually reversed using diaphragmatic breathing to counter the urge to regurgitate.[11] Alongside reassurance, explanation and habit reversal, patients are shown how to breathe using their diaphragms prior to and during the normal rumination period.[11][13] A similar breathing pattern can be used to prevent normal vomiting. Breathing in this method works by physically preventing the abdominal contractions required to expel stomach contents.

Supportive therapy and diaphragmatic breathing has shown to cause improvement in 56% of cases, and total cessation of symptoms in an additional 30% in one study of 54 adolescent patients who were followed up 10 months after initial treatments.[2] Patients who successfully use the technique often notice an immediate change in health for the better.[11] Individuals who have had bulimia or who intentionally induced vomiting in the past have a reduced chance for improvement due to the reinforced behavior.[9][11] The technique is not used with infants or young children due to the complex timing and concentration required for it to be successful. Most infants grow out of the disorder within a year or with aversive training.[14]

Epidemiology

File:Rumination distribution by age.png

Age distribution at diagnosis.[2]

Rumination disorder was initially documented[14][15] as affecting newborns,[5] infants, children[4] and individuals with mental and functional disabilities (the cognitively handicapped).[15][16] It has since been recognized to occur in both males and females of all ages and cognitive abilities.[1][17]

Among the latter, it is described with almost equal prevalence among infants (6–10% of the population) and institutionalized adults (8–10%).[1] In infants, it typically occurs within the first 3–12 months of age.[18]

The occurrence of rumination syndrome within the general population has not been defined.[3] Rumination is sometimes described as rare[1], but has also been described as not rare, but rather rarely recognized.[19] The disorder has a female predominance.[3] The typical age of adolescent onset is 12.9, give or take 0.4 years (±), with males affected sooner than females (11.0 ± 0.8 for males versus 13.8 ± 0.5 for females).[2]

There is little evidence concerning the impact of hereditary influence in rumination syndrome.[8] However, case reports involving entire families with rumination exist.[20]

History

The term Rumination is derived from the Latin word "ruminare", which means to chew the cud.[20] First described in ancient times, and mentioned in the writings of Aristotle, rumination syndrome was clinically documented in 1618 by Italian anatomist Fabricus ab Aquapendende, who wrote of the symptoms in a patient of his.[17][20]

Among the earliest cases of rumination was that of a physician in the nineteenth century, Charles-Édouard Brown-Séquard, who acquired the condition as the result of experiments upon himself. As a way of evaluating and testing the acid response of the stomach to various foods, the doctor would swallow sponges tied to a string, then intentionally regurgitate them to analyze the contents. As a result of these experiments, the doctor eventually regurgitated his meals habitually by reflex.[21]

Numerous case reports exist from before the twentieth century, but were influenced greatly by the methods and thinking used in that time. By the early twentieth century, it was becoming increasingly evident that rumination presented itself in a variety of ways in response to a variety of conditions.[17] Although still considered a disorder of infancy and cognitive disability at that time, the difference in presentation between infants and adults was well established.[20]

Studies of rumination in otherwise healthy adults became decreasingly rare starting in the 1900s, and the majority of published reports analyzing the syndrome in mentally healthy patients appeared thereafter. At first, adult rumination was described and treated as a benign condition. It is now described as otherwise.[22] While the base of patients to examine has gradually increased as more and more people come forward with their symptoms, awareness of the condition by the medical community and the general public is still limited.[1][19][23][24]

In other animals

The chewing of cud by animals such as cows, goats, and giraffes is considered normal behavior. These animals are known as ruminants.[8] Such behavior, though termed rumination, is not related to human rumination syndrome, but is ordinary behavior nonetheless. Involuntary rumination, similar to what is seen in humans, has been described in gorillas and other primates.[25]

See also


References

  1. ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 Papadopoulos, Vassilios; Mimidis, Konstantinos (July-September 2007), "The rumination syndrome in adults: A review of the pathophysiology, diagnosis and treatment", Journal of Postgraduate Medicine 53 (3): 203–206, doi:10.4103/0022-3859.33868, PMID 17699999 
  2. ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 Chial, Heather J; Camilleri, Michael; Williams, Donald E; Litzinger, Kristi; Perrault, Jean (2003), "Rumination syndrome in children and adolescents: diagnosis, treatment, and prognosis", Pediatrics 111 (1): 158–162, doi:10.1542/peds.111.1.158, PMID 12509570, http://pediatrics.aappublications.org/cgi/reprint/111/1/158 
  3. ↑ 3.0 3.1 3.2 Tack, Jan; Talley, Nicholas J; Camilleri, Michael; Holtmann, Gerald; Hu, Pinjin; Malagelada, Juan-R; Stanghellini, Vincenzo (2006), "Functional gastroduodenal disorders", Gastroenterology 130 (5): 1466–1479, doi:10.1053/j.gastro.2005.11.059, PMID 16678560, http://www.romecriteria.org/pdfs/p1466FunctionalGastroduodenal1.pdf 
  4. ↑ 4.0 4.1 ICD-10 entries for rumination syndrome - F98.2, http://apps.who.int/classifications/apps/icd/icd10online/?gf90.htm+f982, retrieved on 2009-08-10 
  5. ↑ 5.0 5.1 ICD-10 entries for rumination syndrome - P92.1, http://apps.who.int/classifications/apps/icd/icd10online/?gp90.htm+p921, retrieved on 2009-08-10 
  6. ↑ 6.0 6.1 6.2 6.3 6.4 Camilleri, Michael; Seime, Richard J, Rumination Syndrome, symptoms, Rochester, Minnesota: Mayo Clinic, http://www.mayoclinic.org/rumination-syndrome/symptoms.html, retrieved on 2009-06-26 
  7. ↑ Amarnath, Rathna P; Abell, Thomas L (October 1986), "The rumination syndrome in adults. A characteristic manometric pattern.", Annals of Internal Medicine 105 (4): 513–518, doi:10.1059/0003-4819-105-4-513 (inactive 2009-09-30), PMID 3752757, http://www.annals.org/cgi/content/abstract/105/4/513 
  8. ↑ 8.0 8.1 8.2 8.3 Ellis, Cynthia R; Schnoes, Connie J (2009), "Eating Disorder, Rumination", Medscape Pediatrics, http://emedicine.medscape.com/article/916297-overview, retrieved on 2009-09-07 
  9. ↑ 9.0 9.1 9.2 LaRocca, Felix E; Della-Fera, Mary-Anne (October 1986), "Rumination: Its significance in adults with bulimia nervosa", Psychosomatics 27 (3): 209–212, PMID 3457391 
  10. ↑ O'Brien, Michael D; Bruce, Barbara K; Camilleri, Michael (March 1995), "The rumination syndrome: Clinical features rather than manometric diagnosis", Gastroenterology 108 (4): 1024–1029, doi:10.1016/0016-5085(95)90199-X, PMID 7698568 
  11. ↑ 11.0 11.1 11.2 11.3 11.4 Chitkara, Denesh K; van Tilburg, Miranda; Whitehead, William E; Talley, Nicholas (2006), "Teaching diaphragmatic breathing for rumination syndrome", Gastroenterology 101 (11): 2449–2452, PMID 17090274 
  12. ↑ 12.0 12.1 Wagaman, JR; Williams, DE; Camilleri, M (1998), "Behavioral intervention for the treatment of rumination", Pediatric Gastroenterology and Nutrition 27 (5): 596–598, doi:10.1097/00005176-199811000-00019, PMID 9822330 
  13. ↑ Johnson, WG; Corrigan, SA; Crusco, AH; Jarell, MP (1987), "Behavioral assessment and treatment of postprandial regurgitation", Gastroenterology 9 (6): 679–684, PMID 3443732 
  14. ↑ 14.0 14.1 Rasquin-Weber, A; Hyman, PE; Cucchiara, S; Fleisher; Hyams; Milla; Staiano (1999), "Childhood functional gastrointestinal disorders", Gut 45 (Supplement 2): 1160–1168, PMID 10457047 
  15. ↑ 15.0 15.1 Sullivan, PB (1997), "Gastrointestinal problems in the neurologically impaired child", Baillieres Clinical Gastroenterology 11 (3): 529–546, doi:10.1016/S0950-3528(97)90030-0, PMID 9448914 
  16. ↑ Rogers, B; Stratton, P; Victor, J; Cennedy, B; Andres, M (1992), "Chronic regurgitation among persons with mental retardation: A need for combined medical and interdisciplinary strategies", American Journal of Mental Retardation 96 (5): 522–527, PMID 1562309 
  17. ↑ 17.0 17.1 17.2 Olden, Kevin W (2001), "Rumination", Current Treatment Options in Gastroenterology 4 (4): 351–358, doi:10.1007/s11938-001-0061-z, PMID 11469994, http://resources.metapress.com/pdf-preview.axd?code=08222k1110283n0m&size=largest 
  18. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named <ref name=
  19. ↑ 19.0 19.1 Fox, Mark; Young, Alasdair; Anggiansah, Roy; Anggiansah, Angela; Sanderson, Jeremy (2006), "A 22 year old man with persistent regurgitation and vomiting: case outcome", British Medical Journal 333 (7559): 133, doi:10.1136/bmj.333.7559.133, PMID 16840471, http://www.labmeeting.com/paper/8505339/fox-2006-a-22-year-old-man-with-persistent-regurgitation-and-vomiting-case-outcome 
  20. ↑ 20.0 20.1 20.2 20.3 Brockbank, EM (1907), "Merycism or rumination in man", British Medical Journal 1 (2408): 421–427, doi:10.1136/bmj.1.2408.421 
  21. ↑ Kanner, L (February 1936), "Historical notes on rumination in man", Medical Life 43 (2): 27–60, OCLC 11295688 
  22. ↑ Sidhu, Shawn S; Rick, James R (2009), "Erosive eosinophilic esophagitis in rumination syndrome", Jefferson Journal of Psychiatry 22 (1), ISSN 1935-0783, http://jdc.jefferson.edu/cgi/viewcontent.cgi?article=1028&context=jeffjpsychiatry 
  23. ↑ Camilleri, Michael; Seime, Richard J, Rumination Syndrome, an overview, Rochester, Minnesota: Mayo Clinic, http://www.mayoclinic.org/rumination-syndrome/, retrieved on 2009-06-26 
  24. ↑ Parry-Jones, B (1994), "Merycism or rumination disorder. A historical investigation and current assessment", British Journal of Psychiatry 165 (3): 303–314, doi:10.1192/bjp.165.3.303, PMID 7994499 
  25. ↑ Hill, SP (May 2009), "Do gorillas regurgitate potentially-injurious stomach acid during 'regurgitation and reingestion?'", Animal Welfare 18 (2): 123–127, ISSN 0962-7286, http://openurl.ingenta.com/content?genre=article&issn=0962-7286&volume=18&issue=2&spage=123&epage=127 

External links

Template:Mental and behavioral disorders Template:Certain conditions originating in the perinatal period



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