Pyomyositis: Some Critical Differential Diagnosis

Pyomyositis is a bacterial infection of the skeletal muscle, commonly known as tropical pyomyositis. Most common organisms include Staphylococcus aureus. While, gram-negative bacteria, anaerobes, and Streptococcus are additional organisms. Although the exact cause of pyomyositis is unknown, bacterial seeding and superficial skin infections are linked to the majority of cases.

It frequently occurs in children. HIV, alcoholism, injectable drug misuse, diabetes mellitus, steroids, hematologic malignancies, and rheumatologic disorders are among the risk factors linked to it in adults.
Pyomyositis is characterized by fever, leucocytosis, mild erythema, discomfort and tenderness in the affected muscle with a distinctive hard woody induration. Although symptoms may progress slowly over weeks, they typically appear quickly over a few days. The muscles in the legs are most commonly affected. However, there may be involvement of many muscles. Pus accumulation occurs in muscle planes only. Later such lesions can fluctuate or spontaneously drain through the skin.

The diagnosis is made by recovery of pus from the affected muscle or surgical investigation Early systemic antibiotics and surgical drainage are part of the treatment. However, antibiotics alone may be effective in early cases.

If untreated, pyomyositis can result in a potentially fatal illness. Many conditions that mimic pyomyositis are included in differential diagnosis. Therefore, it is crucial to rule out other illnesses that could be similar to this one.

References

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