Pyomyositis, a pyogenic skeletal muscle infection, once common only in the tropics, is being seen increasingly frequently in temperate climates. The thigh muscles are most often involved, but the paravertebral muscles rarely so. We report three cases of pyomyositis chiefly affecting the paraspinal muscles of diabetic patients and presenting as lumbago.
In case 1, a 49-year-old woman was admitted for low right back pain and fever. In case 2, a 60-year-old man admitted for low back pain and fever developed severe pain after undergoing a local intramuscular anesthetic injection for lumbago. In case 3, a 68-year-old man suffering from alcoholism and admitted for consciousness disturbance had reported continuous lumbago after undergoing left lumbar laminectomy for lumbar spinal canal stenosis. In all three cases, computed tomography (CT) demonstrated lesions with enhanced rims in the erector spine muscle in these cases. The three patients recovered uneventfully after intravenous antibiotics and, in case 1, a psoas muscle incision. Because the pyomyositis risk in diabetic patients may be enhanced, however, injections and other surgical procedures should be undertaken with due caution.