Rumination syndrome, or Merycism, is an under-diagnosed chronic motility
disorder characterized by effortless regurgitation of most meals following
consumption, due to the involuntary contraction of the muscles around the
abdomen. There is no retching, nausea, heartburn, odour, or abdominal pain
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. 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, with especially high contrast existing between the
presentation of the typical adult sufferer without a mental disability and
the presentation of an infant and/or mentally impaired sufferer. Like related
gastrointestinal disorders, rumination can adversely affect normal functioning
and the social lives of individuals. It has been linked with depression.
Little comprehensive data regarding rumination syndrome in otherwise healthy
individuals exists because most sufferers 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 esophagus, such as gastroparesis and bulimia nervosa. These
symptoms include the acid-induced erosion of the esophagus and enamel,
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 a condition which
affects the functioning of the stomach and esophagus, also known as a
functional gastroduodenal disorder. In patients that have a history of eating
disorders, Rumination syndrome is grouped alongside eating disorders such
as bulimia and pica, which are themselves grouped under non-psychotic
mental disorder. In most healthy adolescents and adults who have no
mental disability, Rumination syndrome is considered a motility disorder
instead of an eating disorder, because the patients tend to have had no control
over its occurrence and have had no history of eating disorders.
Signs and symptoms While the number and severity of
symptoms varies among individuals, repetitive regurgitation of undigested
food after the start of a meal is always present. 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. 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. There is seldom nausea preceding the expulsion, and the
undigested food lacks the bitter taste and odour of stomach acid and bile.
Symptoms can begin to manifest at any point from the ingestion of the meal to
120 minutes thereafter. However, the more common range is between 30 seconds
to 1 hour after the completion of a meal. Symptoms tend to cease when the
ruminated contents become acidic. Abdominal pain, lack of fecal production
or constipation, nausea, diarrhea, bloating, and dental decay are also
described as common symptoms in day-to-day life. These symptoms are not
necessarily prevalent during regurgitation episodes, and can happen
at any time. Weight loss is often observed 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, though this may be expected of the nutrition
deficiencies that often accompany the disorder as a consequence of its
symptoms. Depression has also been linked with rumination syndrome, though
the effects of it on rumination syndrome are unknown.
Acid erosion of the teeth can be a feature of rumination, as can halitosis.
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.
In adults and adolescents, hypothesized causes generally fall into one of either
category: habit-induced, and trauma-induced. Habit-induced
individuals generally have a history of bulimia nervosa or of intentional
regurgitation, 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, which preceded the onset of rumination, often by several months.
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. Based on typical observed features, several
criteria have been suggested for diagnosing rumination syndrome. 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 30 minutes of the completion of a meal.
Patients may either chew the regurgitated matter or expel it. The
symptoms must stop within 90 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 a regurgitant that does not taste sour or
acidic, is generally odourless, is effortless, or at most preceded by a
belching sensation, that there is no retching preceding the regurgitation,
and that the act is not associated with nausea or heartburn.
Patients visit an average of five physicians over 2.75 years before being
correctly diagnosed with rumination syndrome.
= 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.
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" following food intake—which, in long-term patients, may
include ingesting copious amounts to offset malnutrition, 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, unlike
bulimia, rumination is not self-inflicted. Adults 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.
Gastroparesis is another common misdiagnosis. Like rumination syndrome,
patients with gastroparesis often bring up food following the ingestion of a
meal. Unlike rumination, gastroparesis causes vomiting of food, which is not
being digested further, from the stomach. This vomiting occurs several
hours after a meal is ingested, preceded by nausea and retching, and has the
bitter or sour taste typical of vomit. Pathophysiology
Rumination syndrome is a poorly understood disorder, and a number of
theories have speculated the mechanisms that cause the regurgitation, which is a
unique symptom to this disorder. While no theory has gained a consensus, some
are more notable and widely published than others.
The most widely documented mechanism is that the ingestion of food causes
gastric distention, which is followed by abdominal compression and the
simultaneous relaxation of the lower esophageal sphincter. 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. 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.
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. Treatment is different for infants and the mentally
handicapped than for adults and adolescents of normal intelligence. For
adults and adolescents,Biofeedback and relaxation techniques, to be practice
after eating or whenever regurgitation occurs, has proven to be most effective.
Among infants and the mentally handicapped, behavioral and mild
aversive training has been shown to cause improvement in most cases.
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, although some older studies advocate the use of
pinching. In patients of normal intelligence, rumination is not an
intentional behavior and is habitually reversed using diaphragmatic breathing
to counter the urge to regurgitate. Alongside reassurance, explanation and
habit reversal, patients are shown how to breathe using their diaphragms prior
to and during the normal rumination period. 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. Patients who successfully
use the technique often notice an immediate change in health for the
better. Individuals who have had bulimia or who intentionally induced vomiting in
the past have a reduced chance for improvement due to the reinforced
behavior. 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.
Epidemiology Rumination disorder was initially
documented as affecting newborns, infants, children and individuals with
mental and functional disabilities. It has since been recognized to occur in
both males and females of all ages and cognitive abilities.
Among the latter, it is described with almost equal prevalence among infants
and institutionalized adults. In infants, it typically occurs within the
first 3–12 months of age. The occurrence of rumination syndrome
within the general population has not been defined. Rumination is sometimes
described as rare, but has also been described as not rare, but rather rarely
recognized. The disorder has a female predominance. The typical age of
adolescent onset is 12.9, give or take 0.4 years, with males affected sooner
than females. There is little evidence concerning the
impact of hereditary influence in rumination syndrome. However, case
reports involving entire families with rumination exist.
History The term rumination is derived from the
Latin word ruminare, which means to chew the cud. 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.
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.
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.
Although still considered a disorder of infancy and cognitive disability at that
time, the difference in presentation between infants and adults was well
established. 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. 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. 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. Such behavior, though
termed rumination, is not related to human rumination syndrome, but is
ordinary. Involuntary rumination, similar to what is seen in humans, has
been described in gorillas and other primates.
References The Children's Hospital of Philadelphia
External links MayoClinic.org Pediatrics - Rumination
Syndrome - The Mayo Clinic website provides a clear and concise overview of
the disorder. WedMD - Rumination disorder - Web MD.
Provides a general overview of the disease.