Point-of-Care Ultrasound Identifies Pyomyositis Secondary to Intramuscular Testosterone Injection: Report of Two Cases.

BACKGROUND: Intramuscular (i.m.) injections are a commonly utilized route for medication delivery. Intramuscular-associated soft tissue infections are rare and can include pyomyositis and i.m. abscess. Intramuscular testosterone injections have not been previously implicated in causing pyomyositis. Point-of-care ultrasound is an important bedside tool that can identify pyomyositis and differentiate this infection from more common entities such as cellulitis.

CASE REPORTS: We present two cases of i.m. testosterone-associated pyomyositis. In both cases, the physical examination features were consistent with simple cellulitis. However, point-of-care ultrasound evaluation revealed changes consistent with pyomyositis in each case. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Although uncommon, i.m. injections such as testosterone carry a risk of soft tissue infection. As demonstrated in the above cases, ultrasound can be helpful in making the differentiation between simple cellulitis and pyomyositis. The emergency physician should be cognizant of this complication of therapeutic i.m. injections, as well as the diagnostic efficacy of point-of-care ultrasound in evaluating the extent and location of the soft tissue infection.