A 44-year-old Caucasian female with a history of endometriosis is admitted to the intensive care unit due to severe left lower quadrant abdominal pain, nausea and vomiting. With patients’ positive chandelier sign on pelvic examination, leucocytosis, elevated erythrocyte sedimentation rate and elevated C-reactive protein indicated that she had pelvic inflammatory disease (PID). PCR tests were negative for Neisseria gonorrhoeae and Chlamydia trachomatis; however, her blood and urine cultures grew Group A streptococci (GAS) with a negative rapid Streptococcus throat swab and no known exposure to Streptococcus. On further review, patient met criteria for GAS toxic shock syndrome based on diagnostic guidelines. The patient was promptly treated with intravenous antibiotics and supportive care, and she acutely recovered. This case demonstrates a rare cause of PID and an atypical aetiology of severe sepsis. It illuminates the importance of considering PID as a source of infection for undifferentiated bacteraemia.