Dandy-Walker Malformation-Like Condition Revealed by Refractory Schizophrenia: A Case Report and Literature Review.

INTRODUCTION: Dandy-Walker malformation is a rare congenital malformation involving cystic dilatation of the fourth ventricle, enlarged posterior fossa, complete or partial agenesis of the cerebellar vermis, elevated tentorium cerebelli, and hydrocephalus. Previous research highlighted a possible role for the cerebellum in schizophrenia as well as the contribution of underlying brain malformations to treatment resistance. Here, we present a case of a Dandy-Walker malformation-like condition revealed by a refractory schizophrenia in a 24-year-old male patient. We also conduct a literature review of all previously published case reports or case series of co-occurring posterior fossa abnormalities and schizophrenia or psychosis using a PubMed search query to better understand the potential link between these two disorders.

CASE PRESENTATION: A 9-month hospital stay was needed to address the treatment-resistant psychotic symptoms, and the patient continued to experience moderate symptoms despite the prescription of various antipsychotic and antidepressant medications. After an irregular initial medical follow-up, the patient is currently treated with 350 mg daily clozapine and 20 mg daily prazepam and still exhibits moderate anxiety without delirious thoughts, however allowing him to re-enroll at the university. Regarding the literature, 24 cases published between 1996 and 2017 were identified, reviewed and compared to the present case report.

DISCUSSION: This case report and literature review further illuminates the pathophysiology of psychotic disorders including the potential role of the cerebellum, reinforces the importance of a multidisciplinary approach for the neurological and psychiatric management of patients with schizophrenia, and highlights optimal pharmacological management strategies for treatment-resistant schizophrenia.