72 yo M w/ PMHx of HTN, HLD, CKD (not on dialysis), DM and CAD presents to the ED with scrotal pain x 1 week. He is concerned that he has an "abcess" and wanted to be checked. A CT is done and shown below. What's the diagnosis? (scroll down for answer)

Answer: Fournier's Gangrene

• Note CT scan above showing scrotal edema with subcutanteous air 
• Fournier's Gangrene is a form of necrotizing fasciitis of the perineal, perianal and genital regions
• Majority of cases affect males, but can occur in females
• Most common comorbid conditions: DM and ETOH use
• Exam may show cellulitis, crepitus, pain and skin necrosis
• Typically polymicrobial infection
• Early surgical debridement and antibiotics help limit mortality- but still as high as 20-30%
• Once suspected--- call your surgeon!
• Can get advanced imaging including CT scan if diagnosis not clear
• Start broad spectrum antibiotics- vancomycin and carbapenem or piperacillin-tazobactam +/- clindamycin or metronidazole
• Goal is to cover gram positive, gram negative, and anaerobes
• Don't forget blood cultures and fluid resuscitation! 

References:

Thwaini A, Khan A, Malik A, et al. Fournier's gangrene and its emergency management. Postgrad Med J. 2006;82(970):516-519