The Utility of Musculoskeletal Ultrasonography in Diagnosing Pyomyositis: A Comparison With Surgically and Conservatively Treated Cases

Abstract

Objective: The study aimed to determine the accuracy of sonography in diagnosing pyomyositis. Methods: A retrospective review of pyomyositis cases in a government hospital between January 1, 2016 and June 30, 2019 was done. All cases underwent a sonogram for the indication of pyomyositis. Positive purulence for surgical cases and improved laboratory parameters for conservative cases were confirmatory for pyomyositis. Comparison with sonographic results using a 2 × 2 contingency table was done to determine sensitivity and specificity. Results: A total of 122 cases were included. The sonographic results corresponded with 95% of surgical cases and 89% of conservative cases. A lack of false and true negatives for surgical cases resulted in a sensitivity of 100% (95% confidence interval [CI] = 93%–100%) and a specificity of 0% (95% CI = 0%–71%). In conservative cases, sonography had a sensitivity of 92% (95% CI = 82%–97%) and a specificity of 0% (95% CI = 0%–84%) due to a lack of true negatives. Conclusion: Sonography is not limited to primarily as a screening tool but a capable diagnostic imaging choice for pyomyositis, particularly in low-resource settings. The results show the strength of sonography, particularly in the suppurative stage of pyomyositis. [Box: see text]