A rare case of musk myasthenia gravis in a HIV patient

Abstract

Autoimmune disorders have been frequently described in HIV patients but there has been little research on the association between HIV and myasthenia gravis. MuSK myasthenia gravis coexisting with HIV is an even rarer entity. 50 years old lady with HIV and baseline CD4 count of 170, on antiretroviral therapy from 1.5 years, presented with complaints of difficulty swallowing, change in voice and intermittent double vision since 10 months. There was a history of fluctuations. On examination she had bilateral mild lateral gaze palsy with mild asymmetric bifacial weakness. Her gag reflex was weak on both sides. Her CD4 count done 6 months back had increased to 477 and her MRI brain was normal. Myasthenia gravis was strongly suspected. Repetitive Nerve Stimulation showed a decremental response in bilateral median innervated muscles. Her MuSK antibody was positive and Ach receptor antibody was negative, which confirmed the diagnosis of MuSK myasthenia gravis. There was improvement with addition of pyridostigmine and she was later discharged on Pyridostigmine, Prednisolone and Azathioprine. On follow up, the patient is showing sustained improvement. Autoimmune disorders are being increasingly reported with HIV infection since the advent of HAART. MuSK myasthenia gravis with HIV has been reported in very few case reports. The use of immunosuppressants in the treatment of these conditions should be carefully evaluated.