Pyonephrosis by Prevotella disiens and Escherichia coli coinfection and secondary peritonitis in an obstructive uropathy patient: A case report and review of the literature.

Pyonephrosis is an uncommon condition that is associated with suppurative destruction of the renal parenchyma. Upper urinary tract obstruction by renal stones plays an important role in its aetiology. The majority of pyonephrosis is reported to be caused by aerobic bacteria but the role of anaerobes, especially black-pigmented gram-negative anaerobes, namely, Prevotella and Porphyromonas in renal infections, remain poorly defined. In view of the rarity of the event, a case of pyonephrosis by Prevotella disiens and Escherichia coli coinfection complicated by secondary peritonitis in an obstructive uropathy patient is hereby presented. An attempt is being made to review the literature on the infective aetiologies of renal abscess with special reference to anaerobes.