Case Report: Severe adolescent-onset schizophrenia with Capgras syndrome and remission during clozapine-centered treatment after earthquake-related displacement and peer victimization.

Adolescent first-episode psychosis may combine schizophrenia-spectrum, affective, trauma-related, and developmental features, and Capgras syndrome is uncommon in this age group. We report a confidentially de-identified case of a 16-year-old female high-school student with no previous psychiatric admission or known substance use who developed severe insomnia, reduced self-care, external auditory hallucinations, paranoid and referential ideation, Capgras-type misidentification of her father, and a multithemed bizarre delusional system after cumulative psychosocial stressors including earthquake-related displacement, relocation, school transition, peer exclusion, appearance-related mockery, and family-school conflict. Laboratory tests, brain magnetic resonance imaging, electroencephalography, substance screening, and child neurology consultation were unrevealing. DSM-5-TR schizophreniform disorder was the initial working diagnosis; bipolar disorder with psychotic features, schizoaffective disorder, brief psychotic disorder, trauma-related or dissociative phenomena, substance/medication-induced psychosis, autoimmune encephalitis, and temporal lobe epilepsy were considered. Risperidone- and olanzapine-based treatment produced partial but insufficient improvement. Clozapine was initiated at admission week 8 and titrated to 175 mg/day over approximately 4 weeks. Marked improvement was observed by week 2 of clozapine-centered treatment and remission by week 4. At admission week 12, the Clinical Global Impression-Severity score was 1, the Positive and Negative Syndrome Scale score was 45, and the Young Mania Rating Scale score was 4. At 8-month follow-up, the patient remained clinically stable on clozapine 175 mg/day, and the diagnosis was maintained as schizophrenia because the longitudinal course exceeded 6 months. This case highlights the diagnostic complexity of adolescent-onset psychosis with Capgras syndrome, the need to distinguish contextual stressors from primary etiology, and the cautious, monitored consideration of clozapine when severe schizophrenia-spectrum psychosis shows insufficient response to standard antipsychotic trials.