Rumination syndrome

Clinical

• frequent regurgitation of previously ingested food into the mouth that then is rechewed and either swallowed or spit out.
• effortless, not associated with forceful emesis. The infant appears satisfied and calm.
• believed to be a behavioral mechanism for self-stimulation and pleasurable sensation.
• Although children who have rumination often mouth their fingers and fists to initiate a gag reflex, some children learn to ruminate without obvious stimulation
• Chronic rumination may result in malnutrition, electrolyte disturbances, and esophagitis and is associated with a mortality rate of 15% to 25%. 
• Motility studies have revealed that rumination is associated with voluntary abdominal wall contraction and  pharyngeal maneuvers that decrease upper esophageal sphincter pressure.

Who?

• Typically, rumination begins at 5 months of age, although it may begin at any age
• most frequently in mentally retarded children
• Mentally healthy infants who are abused or neglected and preterm neonates who have limited contact with their parents also are at risk for developing rumination syndrome.
• 5 times more common among males than females.
• Rumination responds to increased personal attention and negative reinforcement.

Associations

• can be associated with gastroesophageal reflux and bulimia, making the distinctions between these disorders difficult.

Differential

• Achalasia is characterized by increased lower esophageal pressure, absent or incomplete relaxation of the lower esophageal sphincter, and defective esophageal peristalsis and megaesophagus. Symptoms are insidious in onset and include vomiting, dysphagia, weight loss, slow eating, and failure to thrive. In younger children, coughing, choking, and recurrent pneumonia may be more prominent.
• Gastric outlet obstruction presents with forceful nonbilious emesis, anorexia, and weight loss. Abdominal pain and distension may be noted.
• Sandifer syndrome is associated with reflux and is characterized by abnormal movement of the head and neck that results in unusual posturing. It usually consists of sudden extension of the head and neck into the position of opisthotonos. The movement is not related to the activity, but typically it resolves during sleep. Sandifer syndrome is thought to result in enhanced esophageal clearance of refluxed material.
• Many infants who have physiologic gastroesophageal reflux (GER) manifest no symptoms other than emesis and may appear to ruminate. Dysphagia for both solids and liquids may occur in older children. GER occurs in children who have rumination and vice versa, but GER is not associated with repetitive contractions of the abdominal musculature and often results in irritability rather than a calming effect.
   

References:
Fleisher DR. Functional vomiting disorders in infancy: innocent
vomiting, nervous vomiting, and infantile rumination syndrome. J
Pediatr. 1994;125:S84-S94
Herbst J, Friedland GW, Zboralske FF. Hiatal hernia and "rumination"
in infants and children. J Pediatr. 1971;78:261-265
Mayes SD, Humphrey FJ II, Hanford HA, Mitchell JF. Rumination
disorder: differential diagnosis. J Am Acad Child Adolesc Psychiatry.
1988;27:300-302