PT - JOURNAL ARTICLE AU - Matthew Johnson AU - Ashley Bartscherer AU - Ellis Tobin AU - Marcel Tafen TI - <em>Streptococcus pyogenes</em> peritonitis: a rare, lethal imitator of appendicitis AID - 10.1136/bcr-2019-230490 DP - 2019 Sep 01 TA - BMJ Case Reports PG - e230490 VI - 12 IP - 9 4099 - http://casereports.bmj.com/content/12/9/e230490.short 4100 - http://casereports.bmj.com/content/12/9/e230490.full SO - BMJ Case Reports2019 Sep 01; 12 AB - Streptococcus pyogenes is a common cause of infection. Since 2010, the Centers for Disease Control has noted a 24% rise in invasive S. pyogenes infections with a mortality rate of 10%. We present a case series and review of the English literature. Two patients presented with findings concerning for appendicitis, each underwent laparoscopic appendectomies. Both had diffuse peritoneal inflammation without appendicitis, cultures grew S. pyogenes and both recovered with appropriate antibiotics. Thirty cases were identified in a review of the English literature. The average age was 27 years, 75% were in women, 9% were immunocompromised, 15% had rashes and 88% underwent surgical intervention. Previous work identified female gender, immunosuppression and preceding varicella infection as risk factors for invasive S. pyogenes. Given the similarities to appendicitis, early suspicion can influence antibiotic therapy and possibly improve outcomes.