Psychosis in primary angiitis of the central nervous system involving bilateral thalami: a case report.

OBJECTIVE

To report a case of primary angiitis of the central nervous system (PACNS), a rare inflammatory disease restricted to the central nervous system (CNS), with unusual clinical presentation mimicking schizophrenia.

METHOD: Case report.

RESULTS

A 45-year-old male presented with alteration of consciousness and confusion. Brain magnetic resonance imaging (MRI) scan showed a mass-like enhancing lesion involving bilateral thalami, and biopsy revealed findings compatible with PACNS. The patient was treated with corticosteroids. Psychotic symptoms crystallized over the initial 2 months after the diagnosis and persisted for over a year. Severity of his symptoms improved with gradual normalization of the radiologic findings and antipsychotic medication.

CONCLUSION

Our case highlights the importance of considering PACNS as a differential diagnosis of a tumor-like mass lesion in the CNS and the significance of thalamic involvement in the pathogenesis of psychotic symptoms including delusions and hallucinations.