Primary Bacterial Peritonitis in a Young Man: A Rare Manifestation of Invasive Group A Streptococcal Infection.

Group A Streptococcus (GAS) is a ubiquitous pathogen responsible for a wide range of infections, from superficial to severe invasive forms (iGAS). Among these, primary bacterial peritonitis (PBP) due to GAS is a rare but severe presentation. Recent epidemiological data indicate a significant rise in iGAS cases globally, which may be linked to changes in post-pandemic pathogen circulation. This report describes a case of PBP and streptococcal toxic shock syndrome (STSS) caused by Streptococcus pyogenes in a young man with no known risk factors. To our knowledge, this is one of only 10 cases of PBP in men reported in the literature. In this article, we review the epidemiology, risk factors, clinical manifestations, and management of iGAS, especially in the case of peritoneal involvement. Further research is needed to better understand the pathogenesis and optimize treatment strategies for this severe infection.