Skeletal muscle infarction in diabetes mellitus.

Objective: To analyze the risk factors, clinical features, and methods of diagnosis of diabetic muscle infarction (DMI).

Methods: Three patients with diabetes mellitus (DM) and skeletal muscle infarction were studied, and 49 additional cases reported in the English literature (Medline database search) were reviewed.

Results: Review of all 52 patients with DMI revealed a number of typical features: equal sex distribution; mean age 41.5 years (range 19-81 yrs); a number of risk factors [long duration of DM (mean 15.2 yrs), poor control and microvascular diabetic complications (neuropathy, retinopathy, nephropathy) (94%), and insulin dependent type I DM (77%)]; a characteristic clinical presentation with painful diffuse muscle swelling (100%); and sometimes a muscle mass (44%), predilection for quadriceps (62%), hip adductors (13%) and leg muscles (13%), elevated serum creatine phosphokinase (47%), abnormal sonograms (81%), abnormal magnetic resonance image (MRI) findings (100%), typical histopathologic findings of a muscle infarct (100%) (ultrastructural evidence of microangiography in one patient); and a tendency toward spontaneous resolution although recurrences are common (51%).

Conclusion: Skeletal muscle infarction is a rare complication of long standing, poorly controlled DM associated with multiple end organ microvascular sequelae. Increased clinical awareness is important for early recognition, particularly in a diabetic patient presenting with a painful thigh or leg swelling. MR imaging is the diagnostic study of choice, and in the appropriate clinical setting, may obviate the need for a muscle biopsy.