CPG for Eating Disorders

7.3. Differential Diagnosis of Eating disordersDespite the existence of certain well-defined diagnostic criteria for eating disorders, inclinical practice there are often difficulties relating to the differential diagnosis with otherconditions that require rigorous clinical assessment.In regards with AN, the differential diagnosis must be made with those pathologies that canpresent significant appetite loss and weight loss, even though the main features of AN, such asbody image distortion, the desire to perpetuate weight loss and the fear of becoming fat, are notpresent in all cases:• Mental disorders: depression, anxiety, psychotic disorders and substance abuse• Diabetes mellitus• Tuberculosis• Hyperthyroidism• Neoplasias of the central nervous system• Less frequent: lymphomas, sarcoidosis, Addison’s disease, celiac disease, superiormesenteric artery syndrome (it may sometimes be a complication of AN), AIDS, lactoseintolerance, panhypopituitarism, etc.The differential diagnosis of AN is especially indicated in adult patients, given the atypicalage of onset of the disorder.The differential diagnosis of BN is more limited than AN and includes organic conditionsthat present hyperphagia and weight gain:• Diabetes mellitus• Hypothyroidism• Kleine-Levin Syndrome (idiopathic disorder that especially affects men aged 20-30 yearsand that presents with hypersomnia and hyperphagia).• Hypothalamic lesions• Tumours causing hyperphagia• Major depression, atypical depression, borderline personality disorder (BPD).The differential diagnosis of EDNOS must be performed with pathologies that may presentwith weight loss or gain and/or decreased or increased appetite. The differential trait of EDNOSis body-scheme distortion and excessive and irrational focus on weight and diet.In BED, the differential diagnosis must be performed with the same pathologies describedfor BN and with clinical pictures of impulse control disturbance that may present with bingeeatingepisodes, such as those that occur in BPD.CLINICAL PRACTICE GUIDELINE FOR EATING DISORDERS76