THE SALIVARY GLANDS AND EATING DISORDERS   The spectrum of eating disorders with its psychiatric implications is most frequently seen in young females pursuing thinness. It includes anorexia nervosa (AN) and bulimia nervosa (BN). Patients with AN refuse to maintain normal weight and are visibly thin, have a disturbance in the perception of their weight with an intense fear of obesity, and demonstrate amenorrhea over 3 consecutive cycles. Conversely, BN patients are not underweight and indulge in uncontrolled recurrent episodes of high caloric binge eating. Similar weight concerns lead to forced vomiting following the binges. A high incidence of crossover (AN/BN) exists between AN and BN patients.   The Salivary Gland Center (SGC) has noted salivary gland swellings in patients with BN and AN/BN, but not in patients who do not vomit (AN). Diffuse asymptomatic non-inflammatory salivary gland swellings, usually bilateral parotid and occasionally submandibular, are observed and are directly proportional to the incidence of vomiting. Sialograms are normal, but CT scans confirm the existence of enlarged glands. Microscopically, normal parenchymal architecture with hypertrophy of acinar units has been reported. A work hypertrophy from cholinergic stimulation causing increased salivation during repetitive emesis or an autonomic neuropathy may be etiologic factors. Orally, normal salivary flow from patent non-inflamed duct orifices is evident. The oft-described dental erosions caused by gastric acids can be prevented by good oral hygiene.   Serum chemistry is a vital factor in the diagnosis of BN and AN/BN. Vomiting leads to hypokalemia, hyponatremia and hypochloremia. Elevated bicarbonate levels with metabolic alkalosis can be present. Hyperamylasemia (salivary in origin) is often detected. Cardiac arrythmias, hypotension, hypothermia, and dependent edema are further clinical markers.   Because sialadenopathy is a feature, early recognition of these eating disorders can be facilitated by the SGC. Diagnosis is imperative because the inevitable complications (electrolyte imbalance, cardiovascular abnormalities, emaciation, severe depression, etc.) can be life threatening and mandate hospitalization for successful treatment.   Treatment for the salivary gland swellings requires diet correction and discontinuance of vomiting. Swellings will usually recede. Psychiatric care is necessary and involves individual, family and behavioral therapies. Antidepressant drugs are some value.     Louis Mandel, DDS Director, Salivary Gland Center (212) 305-9982