The Role of MRI in Diagnosis of Diabetic Muscle Infarction : an Underdiagnosed Entity

Muscle infarction is an uncommon complication of long-standing diabetes mellitus. Here, we report the case of a 62-year-old diabetic male patient with acute pain and swelling of the right thigh with signs of mild inflammation but no evidence of infection or myopathy. Initial magnetic resonance imaging (MRI) revealed diffuse swelling and edema of quadriceps muscles with blurred margins. The clinical symptoms showed significant improvement after 1 month of symptomatic treatment. Follow-up MRI performed after 3 months showed remarkable improvement in inflammatory changes with mild residual swelling and edema of the vastus lateralis muscle. In the absence of any systemic signs of infection and laboratory diagnostic markers, the detection of typical features such as hyperintense signal on T2 weighted images or hypo- to isointense signals on T1 weighted images, without localized fluid collection, remains the most useful investigative tool for diagnosing diabetic muscle infarction and obviates the need for invasive procedures like muscle biopsy. Diabetic muscle infarction is a rare complication with distinct clinical presentation, laboratory findings, and MRI features, and can be resolved over a period only by administering adequate supportive treatment. Clinicians should be aware of this complication and always consider it in the differential diagnosis of diabetic patients presenting with acute onset of pain and swelling of the extremities.