Isovaleric Acidemia Coexisting with Schizophrenia: A Case Study

Overview

This case study describes a 25-year-old man diagnosed with both isovaleric acidemia (IVA) and schizophrenia, highlighting the complex interplay between metabolic disorders and psychiatric conditions. The patient exhibited typical IVA metabolic abnormalities alongside chronic schizophrenia symptoms, including delusions and hallucinations, with multiple hospitalizations and treatment adjustments.

Background

Schizophrenia is a severe psychiatric disorder with multifactorial etiology, often accompanied by chronic comorbidities including neurological diseases. Isovaleric acidemia (IVA) is a rare autosomal recessive metabolic disorder caused by deficiency of isovaleryl-CoA dehydrogenase, leading to toxic metabolite accumulation and neurological manifestations. IVA presents in acute neonatal or chronic intermittent forms and may remain asymptomatic in some patients. The metabolic dysregulation in IVA may contribute to neurodevelopmental abnormalities, potentially linking it to schizophrenia pathophysiology.

Data Highlights

Key Findings

• The patient was diagnosed with IVA in childhood following recurrent vomiting and confirmed by elevated isovaleryl-carnitine and genetic testing.
• Schizophrenia symptoms emerged at age 18, including persecutory delusions, thought broadcasting, social withdrawal, and auditory hallucinations.
• Multiple psychiatric hospitalizations occurred with varied antipsychotic and mood stabilizer regimens, showing partial symptom control but persistent psychosis.
• Neurological events included syncopal episodes with limb stiffness, raising concerns about seizure risk and influencing medication adjustments.
• Laboratory findings showed elevated lactate and serum ammonia, consistent with metabolic disturbance from IVA.
• Neuroimaging and EEG were normal, suggesting no structural brain abnormalities despite clinical symptoms.

Clinical Implications

Clinicians should consider metabolic disorders such as IVA in patients presenting with psychiatric symptoms, especially when neurological signs or metabolic abnormalities are present. Careful selection and monitoring of psychotropic medications are essential due to potential seizure risk and metabolic interactions. Multidisciplinary management integrating metabolic and psychiatric care may improve outcomes in such complex cases.

Conclusion

This case highlights the rare coexistence of IVA and schizophrenia, suggesting a possible metabolic contribution to psychiatric pathology. Recognition of such associations is important for comprehensive diagnosis and tailored treatment strategies.

References

1. Schizophrenia and Comorbidities Overview, 2022 -- Impact and Associations
2. IVA Discovery and Genetic Basis, 1966/Recent Reviews -- Isovaleric Acidemia Pathophysiology
3. UK Cohort Study on Neurological Disease Risk in Schizophrenia, 2020 -- Neurological Comorbidities
4. Metabolic Syndrome Prevalence in Schizophrenia, 2019 -- Metabolic Comorbidities