TEMPERATE PYOMYOSITIS AT 2 COMMUNITY HOSPITALS

In a retrospective review of 430,000 hospital admissions at two commun ity hospitals from 1981 to 1996, 28 cases of primary temperate pyomyos itis were identified. The muscle most commonly affected was the iliops oas (46%). Staphylococcus aureus was the predominant organism (12 of 2 0 positive cultures, 60%). The remaining 10 cultures yielded Streptoco ccus species in several cases and various other organisms including Es cherichia coli, Proteus mirabilis, Peptococcus magnus, Salmonella, and Mycobacterium tuberculosis. All patients presented with muscle pain a nd fever. Patient characteristics included trauma (39%), injection dru g use (25%), diabetes mellitus (21%), and human immunodeficiency virus -positive status (10%). The erythrocyte sedimentation rate and leukocy te count at admission were elevated in 81% and 79% of patients, respec tively. No patient had eosinophilia. Blood cultures were positive for organisms in 64%. Computed tomography, magnetic resonance imaging, rad ionuclide scanning, and ultrasonography were diagnostically helpful. T reatment consisted of antibiotic therapy with or without surgical or p ercutaneous drainage. In contrast to tropical pyomyositis, which occur s largely in immunocompetent hosts and is due almost exclusively to S. aureus, temperate pyomyositis is becoming more common in immunocompro mised or chronically ill patients and is associated with a wide variet y of organisms. Pyomyositis, which mimics many diseases, should be inc luded in the differential diagnosis of all patients with localized pai n and fever.