-Case Reports-

New-Onset Schizophrenia in an Adolescent after COVID-19

Masatsugu Ishii^1,*, Kakusho C Nakajima-Ohyama^2,3,*, Hayato Saito^2,4, Tomoyuki Ohya², Shotaro Uchiyama^2,3, Mizuho Takahashi^5,6, Masanori Sakamaki⁵, Akihiro Watanabe¹, Jun-ichi Inoue¹, Tetsuro Sekine⁷, Amane Tateno² and Yasuhiro Kishi³

¹Department of Emergency and Critical Care Medicine, Nippon Medical School Musashi Kosugi Hospital, Kanagawa, Japan
²Department of Neuropsychiatry, Nippon Medical School Hospital, Tokyo, Japan
³Department of Neuropsychiatry, Nippon Medical School Musashi Kosugi Hospital, Kanagawa, Japan
⁴Department of Mental Health, Nippon Medical School Chiba Hokusoh Hospital, Chiba, Japan
⁵Department of Neurology, Nippon Medical School Musashi Kosugi Hospital, Kanagawa, Japan
⁶Department of Neurology, Nippon Medical School Hospital, Tokyo, Japan
⁷Department of Radiology, Nippon Medical School Musashi Kosugi Hospital, Kanagawa, Japan
^*Contributed equally

Schizophrenia develops during adolescence. Maternal infections during the fetal period increase the incidence of schizophrenia in children, which suggests that the pathogenesis involves neuroinflammation. Here, we report a case of new-onset schizophrenia in a 16-year-old boy after COVID-19. After developing COVID-19, he entered a catatonic state 4 days later and was hospitalized. Benzodiazepines alleviated his catatonia, but hallucinations and delusions persisted. Encephalitis and epilepsy were excluded by magnetic resonance imaging (MRI), encephalography, and cerebrospinal fluid examination. Psychosis persisted after the virus titer declined and the inflammatory response subsided. Moreover, the patient exhibited delusions of control-a Schneider's first-rank symptom. Schizophrenia was diagnosed, and olanzapine improved his symptoms. He had a brief history of insomnia before COVID-19 but his symptoms did not satisfy the ultra-high-risk criteria. However, COVID-19 may have facilitated development of schizophrenia through neuroinflammation and volume reduction in the gray matter of the right medial temporal lobe. This case demonstrates that infectious diseases in adolescents should be carefully managed, to prevent schizophrenia.

J Nippon Med Sch 2025; 92: 287-295

Keywords
schizophrenia, COVID-19, first-episode psychosis, neuroinflammation

Correspondence to
Kakusho C Nakajima-Ohyama, MD, PhD, Department of Neuropsychiatry, Nippon Medical School Musashi Kosugi Hospital, 1-383 Kosugi-cho, Nakahara-ku, Kawasaki, Kanagawa 211-8533, Japan
kakusho-ohyama@nms.ac.jp

Received, August 11, 2023
Accepted, February 9, 2024