<prompt> Fournier gangrene is caused by:Cl. WelchiProteusStreptococcusMixed infection  <response>: Ref: Microbiology by Ananthanarayan and Paniker, 8th ed. pg. 226, 270-75 Fournier gangrene, is defined as a polymicrobial necrotizing fasciitis of the perineal, perianal, or genital area. In the majority of cases Fournier gangrene is a mixed infection caused by both aerobic and anaerobic bacteria.Causal Agents Wound cultures from patients with Fournier gangrene reveal that it is a polymicrobial infection with an average of 4 isolates per case. Escherichia coli is the predominant aerobe, and Bacteroides is the predominant anaerobe that causes Fourniers gangrene Other common microflora include the following: Proteus Staphylococcus Enterococcus Streptococcus Pseudomonas Clostridium Klebsiella 