To the Editor: Vaginal ring pessaries are frequently used as long-term treatment for pelvic relaxation in older women, especially those deemed to be poor surgical candidates. These pessaries require monthly monitoring and toilet to prevent local erosive complications.1 One previous case of bilateral ureteral obstruction and urosepsis secondary to a ring pessary has been reported.2 We report a case of pyelonephritis, Gram-negative bacteremia, and unilateral hydronephrosis in a woman with known renal calculi in whom the pessary was initially overlooked as the source of the ureteral obstruction. An 85-year-old female nursing home resident was admitted to the hospital from the Emergency Department with a 1-day history of lower abdominal pain, vomiting, headache, confusion, and visual hallucinations. The patient's past medical history was remarkable for bilateral staghorn calculi and recurrent urinary tract infections. She had previously been treated with prophylactic TMP-SMZ which was stopped because of urinary colonization with resistant organisms. She was gravida V, para 5, and had a flexible Gellhorn vaginal pessary placed at an unknown date because of pelvic relaxation associated with a large cystocoele and rectocoele. Initial vital signs included a core temperature of 39° C, pulse of 111 bpm, and a blood pressure of 167/112 mm Hg. Her examination was remarkable only for mild diffuse abdominal tenderness with an in-situ ring pessary upon pelvic examination. Initial laboratory data showed a white cell count of 17,600 with 83% neutrophils and 10% bands, creatinine was 1.6 mg/dL (baseline), and urinalysis was consistent with infection. The patient was treated medically for pyelonephritis with intravenous ampicillin and gentamicin; urine and blood cultures were subsequently positive for pan-susceptible Proteus mirahilis. She showed little improvement, and on hospital day 2, the white cell count increased to 22,000. Her fever persisted, and the creatinine rose to 2.5 mg/dL on hospital day 4. A renal ultrasound showed marked left hydronephrosis with at least one large calculus in the left renal pelvis (Figure 1). She underwent cystoscopy and retrograde pyelography, which revealed a moderately inflamed bladder, distorted trigone, and marked dilation of the left upper collecting system and ureter extending to the level of the ureterovesical junction without an obvious obstructing calculus (Figure 2). Ureterodilation and placement of a no. 6 French double-J ureteral stent was accomplished successfully. The vaginal pessary was identified as the cause of the ureterovesical junction obstruction. Once this was removed, the patient defervesced within 24 hours, and her white cell count and creatinine quickly became normal. . Renal ultrasound shows marked hydronephrosis of the left kidney (18 cm, with at least one calculus in the area of the renal pelvis. The right kidney was of normal dimensions (9.9 cm). . Retrograde pyelography at cystoscopy showed opacification of a significantly dilated left ureter and left upper collection system. No stone is identified. Uterine prolapse is a common condition in older women. Obstructive uropathy has been reported as a complication, preventable with the use of a vaginal ring pessary in patients who are not candidates for surgical correction. The vaginal ring pessary should not be overlooked, however, as a potential cause of unilateral ureteral obstruction, even in patients with known renal calculi. The appropriate management of pyelonephritis in older women with an in-situ vaginal pessary may require pessary removal in addition to antibiotics, especially if hydronephrosis is identified.