Anorexia nervosa or pediatric acute-onset neuropsychiatric syndrome? A case report

Pediatric Acute-Onset Neuropsychiatric Syndrome (PANS) is a rare heterogeneous condition characterized by rapid onset obsessions/compulsions and/or food restriction with at least two accompanying acute-onset neuropsychiatric symptoms. PANS is currently considered an exclusionary diagnosis with considerable overlap with psychiatric disorders including obsessive compulsive disorder, tics, and eating disorders. Little is known about the crossover between eating disorders and PANS, and there is minimal guidance on diagnostic and treatment considerations for these patients. This case report describes a 9-year-old female who presented for an initial assessment to a specialty outpatient eating disorder treatment center due to restrictive eating, fear of weight gain, body image disturbance, and obsessive-compulsive compensatory behaviors. She met diagnostic criteria for other specified feeding and eating disorder (OSFED)/atypical nervosa (AAN) and received family-based treatment (FBT) to target food restriction through parent-led refeeding. Despite weight stabilization and nutritional improvement in FBT, the patient experienced severe progressive functional deterioration. The patient was subsequently evaluated by an immune behavioral health (IBH) clinic and diagnosed with PANS. Treatment included gradual transition in care from the eating disorder clinic for AAN to IBH and sleep clinics for management of remaining neuropsychiatric symptoms. This report highlights a unique case of a patient with PANS features and body image/weight-driven food refusal. This case has potential implications for how eating disorder specialty providers asses for possible overlapping PANS. Criteria prompting consideration for PANS may include a combination of acute-onset restrictive eating, prepubertal body image disturbance, and progressive functional impairment and/or developmental regression despite weight restoration. This case also highlights implications of care coordination and triage across specialty clinics.