We report a 73-year-old woman with sporadic inclusion body myositis (s-IBM) and a T-cell chronic lymphocytic leukaemia (T-CLL). The s-IBM diagnosis was based on clinical symptoms and muscle biopsy showing inflammatory infiltrates and rimmed vacuoles with 15 18 nm diameter tubulofilamentous inclusions on ultrastructural examination. The inflammatory infiltrates consisted of CD8+ T-lymphocytes and macrophages. The diagnosis of a CD8+ T-CLL was based on peripheral blood samples and bone marrow aspiration. The postmortem analysis of skeletal muscle showed fascicular atrophy, which may support a neurogenic component in s-IBM and the analysis of the brain showed only a few diffuse plaques in different cortical regions and occasionally neuritic plaques. A pathophysiological analogy between s-IBM and Alzheimer's has been suggested on the basis of similarities in protein accumulation in muscle of s-IBM patients and brain of Alzheimer's patients. However, we were unable to detect any changes suggestive of Alzheimer's disease in the brain of the s-IBM patient presented here.