Imaging of Group B Streptococcus infection in pyonephrosis: a case report.

Pyonephrosis is hydronephrosis accompanied by a bacterial infection in the kidney, causing suppurative destruction of the renal parenchyma; this condition is an emergency and usually associated with stones or chronic urinary tract infections. Urinalysis is typically inaccurate for establishing the diagnosis, as bacteriuria may not manifest due to ureteral obstruction. We reported a 55-year-old male patient with flanks pain and an account of stone expulsion.