Rumination : A Critical Review of Diagnosis and Treatment

umination, an uncommon disorder occurring from infancy throughout adulthood, is derived rom the Latin ruminare, "to chew the cud." Merycism, derived from the Helenic, is the act of postingestive regurgitation of food from the stomach back into the mouth, followed by chewing and reswallowing [1]. The two terms are often used interchangeably. Rumination is associated with medical complications such as aspiration pneumonia, electrolyte abnormalities, and dehydration [2] and is considered in the differential diagnosis of vomiting [3] and failure to thrive [4] in infants and young children. From latency through adulthood, rumination frequently has a benign course [5]. Recently it has been associated with bulimia [6,7], anorexia nervosa, and depression [5,105,109]. Past studies have ascribed the disorder to lack of emotional reciprocity and attunement between mother and child stemming primarily from maternal depression and anxiety [8-10]. Medical disorders such as gastroesophageal reflux and hiatal hernia [2,8,11,12], also are present in the population of ruminating children. Applications of formal behavioral contingencies in treatment have led to describing ruminatory activity as a habit disorder [13-15]. In DSM III [16] rumination is designated as a disorder of infancy [307.53]. The infant shows "a characteristic position of straining and arching the back with sucking tongue movements and the gaining of satisfaction with rumination" [16]. Diagnostic criteria include repeated regurgitation without nausea or associated gastrointestinal illness for at least one month following a period of normal functioning. Weight loss or failure to make expected weight gain occur often [16]. Irritability is noted between regurgitations and hunger is often inferred by the observer. Although the disorder occurs most frequently after 3 months of age, it has been reported in a 3-week old infant [17] and in the neonatal intensive care unit [4]. Consequent failure to thrive with malnutrition may produce severe developmental delays [15]. Rumination has been described in families over four generations, and learning to ruminate by imitation has been suggested [18]. Rumination may be underreported, with only complicated cases (malnutrition, electrolyte disturbances, hiatal hernia) referred to a gastroenterologist and minor cases treated by parent or primary physician. Rumination in anorexia nervosa and bulimia may be underreported due to omission of inquiry in the systematic medical history and reluctance of patients to volunteer specific clinical information [5,6,7,109]. The course of rumination may depend on the age of the patient and the severity of the complications. Mortality can be as high as 25% to 40% in infants [19]. Although the infant may manifest hyperphagia, postingestive regurgitation leads to progressive malnutrition (ie, a sham eating sequence). In the ruminating adolescent bulimia and affective disorder may be present [7]. Rumination in adults has been associated with gastric