Understanding Psychosis in a Veteran With a History of Combat and Multiple Sclerosis

Discussion

Presently, treatment preferences for MS-related psychosis are divided between atypical antipsychotics and glucocorticoids. Some suggest that the treatment remains similar between MS-related psychosis and primary psychotic disorders in that atypical antipsychotics are the standard of care.¹² A variety of atypical antipsychotics have been used successfully in case reports, including zipradisone, risperidone, olanzapine, quetiapine, and aripiprazole.^13,14 First-generation antipsychotics and other psychotropic drugs that can precipitate extra-pyramidal AEs are not recommended given their potential additive effect to motor deficits associated with MS.¹² Alternatively, several case reports have found that MS-related psychotic symptoms respond to glucocorticoids more effectively, while cautioning that glucocorticoids can precipitate psychosis and depression.^15,16 One review article found that 90% of patients who received corticosteroids saw an improvement in their psychotic symptoms.²

Finally, it is possible that our patient’s neuropsychiatric symptoms can be explained by autoantibody formation in response to toxin exposure during his time in Afghanistan. In a pilot study of veterans with GWI, Abou-Donia and colleagues found 2-to-9 fold increase in autoantibody reactivity levels of the following neuronal and glial-specific proteins relative to healthy controls: neurofilament triplet proteins, tubulin, microtubule-associated tau proteins, microtubule-associated protein-2, myelin basic protein, myelin-associated glycoprotein, glial fibrillary acidic protein, and calcium-calmodulin kinase II.^17,18 Many of these autoantibodies are longstanding explicit markers for neurodegenerative disorders, given that they target proteins and antigens that support axonal transport and myelination. Still Gulf War veteran status has yet to be explicitly linked to an increased risk of MS,¹⁹ making this hypothesis less likely for our patient. Future research should address the clinical and therapeutic implications of different autoantibody levels in combat veterans with psychosis.

Conclusion

For patients with MS, mood disorder and psychotic symptoms should warrant a MRI given the possibility of a psychiatric manifestation of MS relapse. Ultimately, our patient’s presentation was inconsistent with the expected clinical presentations of both a primary psychotic disorder and psychosis as a manifestation of MS. His late age at his first psychotic break is atypical for primary psychotic disease, and the lack of MRI imaging done at his initial psychotic episodes cannot exclude a primary MS diagnosis. Still, his lack of MRI findings at his most recent hospitalization, negative symptomatology, and strong history of schizophrenia make a primary psychotic disorder likely.

Following his future clinical course will be necessary to determine the etiology of his psychotic episodes. Future episodes of psychosis with neurologic symptoms would suggest a primary MS diagnosis and potential benefit of immunosuppressant treatment, whereas repeated psychotic breaks with minimal temporal lobe involvement or demyelination as seen on MRI would be suspicious for separate MS and psychotic disease processes. Further research on treatment regimens for patients experiencing psychosis as a manifestation of MS is still necessary.