Immune checkpoint inhibitor-related myositis: case series and review of current diagnostic and therapeutic recommendations
DOI:
https://doi.org/10.67667/NEU.v27i2.239Keywords:
immune checkpoint inhibitors, immunotherapy, myositis, myocarditis, neurological complicationsAbstract
Background: Immune checkpoint inhibitors (ICI) have significantly improved survival in numerous malignancies, but carry a significant risk of severe immune-mediated adverse events. Neurological complications are relatively rare, but are associated with a high risk of disability and significant mortality.
Objective: To present two clinical cases of patients who developed severe immune-mediated myositis following ICI therapy and to summarize the current recommendations for diagnosis and treatment.
Methods: Two patients on Nivolumab/Ipilimumab or Pembrolizumab treatment developed myositis, predominantly affecting the bulbar and respiratory muscles. The diagnostic approach included clinical assessment, laboratory investigations, electromyography, imaging studies, and cardiological screening. A review of current literature on the diagnosis and treatment of neurological immune-mediated complications was performed.
Results: Both patients developed severe immune-related myositis with bulbar and respiratory muscle weakness, markedly elevated muscle enzyme levels, and electromyographic findings consistent with myogenic injury. Despite the timely initiation of immunosuppressive therapy, both of them had a fatal outcome.
Conclusion: ICI-related myositis is a rare, but potentially life-threatening complication that requires early recognition, prompt discontinuation of immunotherapy, appropriate immunosuppressive treatment, and a multidisciplinary approach involving neurologists, oncologists and cardiologists. Active screening for concomitant myocarditis is essential for improving patient outcomes.
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