Objective:

Not applicable. 

Background:

Hydroxychloroquine is a rare cause of vacuolar myopathy generally presenting as mild to moderate proximal muscle weakness with laboratory findings suggestive of muscle destruction. Infrequently, it has been associated with severe weakness, dilated cardiomyopathy, dysphagia, and respiratory insufficiency. Voice changes, including dysphonia and dysarthria, may be an underrecognized symptom of hydroxychloroquine-mediated myopathy. 

Design/Methods:

Not applicable. 

Results:

An 80-year-old male presented with profound weakness, dysphonia, weight loss, and volume overload concerning for heart failure exacerbation. History was significant for progressive weakness, weight loss, and worsened cardiac function for one year, after the initiation of hydroxychloroquine and low-dose prednisone for rheumatoid arthritis.  Neurological examination was notable for proximal muscle weakness with diffusely reduced muscle volume and a hypophonic and flaccid dysarthria with weakened cough. Initial laboratory studies showed elevated creatinine kinase, transaminases, lactate dehydrogenase, and B-type natriuretic peptide. Magnetic resonance imaging of the spine was unremarkable. Electromyography was significant for a diffuse, proximal-predominant myopathy. Biceps muscle biopsy demonstrated vacuolated fibers with acid phosphatase activity denoting lysosomal dysfunction, most consistent with hydroxychloroquine myopathy. Type 2B atrophy was also present, suggesting additional myopathy secondary to malnutrition, corticosteroids, and disuse. Hydroxychloroquine and prednisone were discontinued, with some improvement in weakness and dysphonia within one week. Though the patient had concordant valvular disease, he had significantly reduced cardiac function over the same period as his weakness.  Additionally, his hospital course was complicated by pneumonia, suggesting respiratory dysfunction from muscle weakness and reduced cough ability. 

Conclusions: