Diagnosis of pediatric urolithiasis: role of ultrasound and computerized tomography.

PURPOSE: Pediatric urolithiasis is believed to be uncommon, and may present without the classic symptoms of renal colic. The objectives of this study were to describe the presenting features and radiographic evaluation of pediatric urolithiasis, and to determine the accuracy of ultrasound and unenhanced computerized tomography (CT) in detecting urolithiasis. MATERIALS AND METHODS: We retrospectively reviewed the charts of children 0 to 18 years old with urolithiasis. Data collected included age, sex, race, presenting symptoms, radiographic studies performed during initial evaluation, calculus location and family history of urolithiasis. RESULTS: A total of 75 patients had complete data for analysis. Of these patients 54 (72%) had urolithiasis symptoms (flank pain, gross hematuria or both). Patients with urolithiasis symptoms were older at diagnosis (median age 11.9 years vs 1.0 years, p <0.001) and were more likely to have a family history of urolithiasis (54% vs 14%, p = 0.002). The 39 CTs performed were accurate in detecting calculi in children with urolithiasis symptoms (96% to 100%) and in those without symptoms (100%). The 36 ultrasounds performed had more variable accuracy in children with urolithiasis symptoms (33% to 100%) vs those without symptoms (89%). Ultrasound failed to detect urolithiasis in 41% of the patients with urolithiasis symptoms, compared to 5% with CT. CT was also highly accurate regardless of calculus location (89% to 100%), whereas ultrasound was again more variable (kidney 90%, kidney and ureter 75%, ureter alone 38%). CONCLUSIONS: Ultrasound failed to detect calculi in 41% of the children with urolithiasis symptoms, whereas CT was highly accurate in all situations. Unenhanced CT should be performed in all children with persistent urolithiasis symptoms and nondiagnostic ultrasound.

A phase I and pharmacodynamic study of sequential topotecan and etoposide in patients with relapsed or refractory acute myelogenous and lymphoblastic leukemia.

We designed a pharmacokinetic and pharmacodynamic phase I study of sequential topotecan (2.55-6.3mg/m2) by 72h infusion followed by five daily doses of etoposide for patients with refractory acute leukemia based upon synergistic anti-tumor activity of topoisomerase I and II inhibitors in vitro. Eight of the 29 patients achieved bone marrow aplasia and two patients achieved clinical remission. Common grade 3-4 toxicities included hepatic and gastrointestinal dysfunction, and correlated with increased steady-state plasma topotecan concentration. The predicted up-regulation of topoisomerase II activity by topoisomerase I inhibition was not observed at this dose and schedule and may provide insight into the modest anti-leukemia activity of the regimen.