Papers of the Week

 is a gram-positive bacillus in the female genital tract believed to be a commensal organism that inhibits the growth of more virulent pathogens.  is a gram-negative bacillus species also typically commensal in the female genital tract. as the primary causative agent in perinephric abscesses and bacteremia has been documented, albeit very uncommon and opportunistic.  is not classically associated with perinephric abscesses but has been implicated in rare cases of pelvic inflammatory disease and tubo-ovarian abscesses. In this report, we present a 26-year-old immunocompetent woman with a recent history of nephrolithiasis treated with lithotripsy, ureteral stent placement and removal, and antibiotics who was admitted for fever and severe right flank pain. Imaging showed a right-sided renal and perinephric abscesses colonized by  and . Blood cultures were also positive for species. Per literature review, intravenous ceftriaxone and metronidazole were administered with successful resolution of abscesses and negative repeat blood cultures. To our knowledge, this is the first case of simultaneous renal system abscesses caused by and species. Nephrolithiasis and prior antibiotics likely contributed to the opportunistic pathogenesis in this otherwise immunocompetent patient.