AZT Myopathy and HIV-1 Polymyositis: One Disease or Two?

PURPOSE: This paper discusses the association between inflammatory and mitochondrial pathologies in patients with HIV-1/AIDS treated with zidovudine (AZT). METHODS: We present the clinical and pathological details of a 52-year-old HIV-1 positive male who presented with progressive muscle weakness. We also review the current literature and address the debated pathogenesis of the inflammatory pathology. RESULTS: Muscle biopsy revealed evidence of both HIV-1 polymyositis and AZT myopathy. Six months after initiation of corticosteroid therapy and discontinuation of AZT, the patient's symptoms had greatly improved. The biopsy was repeated to show that both pathologies had resolved. CONCLUSIONS: The perceived overlap in the pathological spectra of HIV-1 polymyositis and AZT myopathy has produced some debate on causation and treatment. Unfortunately, there have been very few reports where a repeat biopsy following a drug washout period confirmed resolution of the pathology. Furthermore, affected patients have not been treated in a uniform fashion. Whether this represents one disease or two remains uncertain. The clinical relevance of this issue lies in the potential for harm from the unnecessary use of corticosteroids. This question may be best addressed by a randomized clinical trial.