Intervention unneeded for most lower pole stones

June 1, 2006

Paris-Most patients with asymptomatic lower pole calyceal stones can be followed safely without treatment, with a small minority of them requiring surgical intervention in the long-term, according to Turkish researchers who presented the results of a prospective study at the 2006 European Association of Urology annual congress here in Paris.

The intervention time of asymptomatic lower pole stones remains a disputed issue among practicing urologists worldwide.

At the beginning of the study, all patients underwent a detailed evaluation including a CT scan, intravenous pyelography, urine analysis and 24-hour urine samples on a random dietary regimen to determine volume, oxalate, calcium, citrate, uric acid, and creatinine. At each visit, the investigator performed a history regarding the development of symptoms, UTIs and hematuria, physical examination, serum creatinine level, urine analysis and a 24-hour urine sample (when indicated). Repeat computed tomography examinations were performed on even years and ultrasound was performed on odd years. X-ray examinations were performed between visits.

Little intervention needed

Results demonstrated that 75% of the patients (18 of 24) required medical therapy in the form of special dietary regimens, based on the results of metabolic evaluations conducted. Progression in stone size was seen in nine of 27 renal units (33.3%), with three units (11.1%) requiring intervention.

Dr. Inci noted that three stones passed spontaneously without symptoms, and three patients developed pain during follow-up, two of whom received analgesic treatment and subsequently passed stones without needing further treatment.

None of the study patients suffered a pyelonephritic attack during follow-up.

"Even though these patients showed that there was no need for intervention in the first 2 years of follow-up, three patients, or 11.1%, required urologic intervention at the 30th, 62nd, and 67th months of the follow-up, respectively," Dr. Inci said.

"This study shows that the urologist can calmly follow up the vast majority of patients with asymptomatic lower pole calyceal stones without any acute imminent danger of an emergency intervention to remove the stones."

He conceded that because one-third of the patients with lower pole calyceal stone formation demonstrated stone progression and advancement of their stone disease, prudent urologists should provide in-depth, proper counseling about intervention measures should the stones become so large as to require an emergency procedure.