Multidisciplinary Diagnostic and Rechallenge Workflow for Suspected Escitalopram-Associated Neutropenia in Adolescent...

Selective serotonin reuptake inhibitors are evidence-based pharmacologic treatments for obsessive-compulsive disorder (OCD) in adolescents; however, hematologic adverse effects such as leukopenia and neutropenia are rare and incompletely characterized. Management becomes particularly challenging when an effective medication is suspected to contribute to clinically significant hematologic abnormalities. This case report describes a multidisciplinary diagnostic and monitoring workflow for evaluating suspected escitalopram-associated neutropenia in a 14-year-old female with moderate-to-severe OCD and substantial functional impairment. The patient was initially treated with escitalopram, titrated from 10 mg/day to 20 mg/day, resulting in a 39-55% reduction in symptom severity as assessed by retrospectively reconstructed Children's Yale-Brown Obsessive Compulsive Scale (CY-BOCS) scores. Persistent leukopenia and neutropenia identified during routine complete blood count (CBC) monitoring prompted escitalopram discontinuation and a structured multidisciplinary evaluation involving hematology, rheumatology, infectious diseases, allergy and immunology, endocrinology, neurology, and cardiology. Extensive investigations, including laboratory testing, peripheral blood smear examination, brain magnetic resonance imaging, and pelvic ultrasonography, did not identify a definitive alternative etiology. Following medication discontinuation, white blood cell counts did not normalize and OCD symptoms relapsed despite cognitive behavioral therapy with exposure and response prevention, delivered in nine weekly sessions by a clinical psychologist. After multidisciplinary risk-benefit assessment and shared decision-making with the patient and legal guardian, escitalopram rechallenge was initiated using gradual dose escalation from 5 mg/day to 20 mg/day over three weeks, with weekly CBC monitoring, predefined stopping criteria, and infection surveillance. The final CY-BOCS score improved to 11/40 (65% reduction from baseline), while hematologic parameters remained stable. The procedural objective of this report is to present a reproducible multidisciplinary framework for diagnostic evaluation, risk stratification, monitoring, and cautious pharmacologic rechallenge in adolescents with suspected SSRI-associated hematologic abnormalities.