Pyomyositis
![](/Images/godic/202502/05/Pyomyositis_MRI4106.jpg")
![CT with IV contrast showing enlargement and heterogeneous hypodensity in the right pectoralis major muscle. A focal abscess collection with gas within it is present medially. There are enlarged axillary lymph nodes and some extension into the right hemithorax. Note the soft tissue and phlegmon surrounding the right internal mammary artery and vein. The patient was HIV+ and the pyomyositis is believed to be due to direct inoculation of the muscle related to parenteral drug abuse. The patient admitted to being a](/Images/godic/202502/05/CT_pyomyositis4106.jpg")
![CT exam showing a multiloculated fluid collection in the left gluteus minimus muscle found to be a staph aureus pyomyositis in a 12-year-old healthy boy.](/Images/godic/202502/05/Tropical_pyomyositis_CT4107.JPG")
![Axial T1 weighted fat suppressed post IV gadolinium contrast enhanced MRI image showing a mutliloculated bacterial abscess in the left gluteal muscle which grew Staphlococcus Aureus (methicillin sensitive) thought to be due to tropical pyomyositis.](/Images/godic/202502/05/Axial_T1_FS_Post_Gad_tropical_pyomyositis4107.JPG")
Pyomyositis, also known as tropical pyomyositis or myositis tropicans, is a bacterial infection of the skeletal muscles which results in a pus-filled abscess. Pyomyositis is most common in tropical areas but can also occur in temperate zones.