No abstract

Background Urinary cytology is routinely used in the diagnosis of urothelial neoplasms, with good sensitivity for high‐grade urothelial carcinoma (HGUC) but less so for low‐grade urothelial neoplasm (LGUN). There is significant interobserver and interinstitutional variability, especially for the atypical category. The Paris system for reporting urinary cytology (TPS) was introduced to better define the various categories, especially atypical cytology. Methods We retrospectively reviewed 630 atypia of undetermined significance (AUS) cases and reclassified them based on TPS. In total, 501 cases previously reported as negative for malignancy had their medical records reviewed to serve as negative controls. Results Of 630 AUS cases, 299 (47.5%) were reclassified as negative for HGUC (NHGUC), 313 (49.7%) as atypical urothelial cells (AUCs) and 18 (2.9%) as suspicious for HGUC (SHGUC). Based on our institution's previous reporting system, the rate of underlying or subsequent HGUC was 2.8% for AUS, and 0% for negative. When AUS cases were reclassified under TPS, the rates were 1.5% for NHGUC, 4.8% for AUC, and 0% for SHGUC. Review of medical records showed that patients with AUS were more likely to be followed‐up compared with those with negative urine cytology (77.8% compared with 54.3%), particularly those under the care of non‐urologists. Conclusions AUS diagnosis is associated with more patient follow up compared with NEG urine particularly among non‐urologists. Reclassifying according to TPS results in significant reduction in the rate of AUS and thus unnecessary testing. This reduction however may be at the expense of slightly decreased detection rate of HGUC.

Introduction: As early detection of hydronephrosis increases, we require better methods of distinguishing between pediatric patients who require pyeloplasty vs. those with transient obstruction. Gravity-assisted drainage (GAD) as part of a standardized diuretic renography protocol has been suggested as a simple and safe method to differentiate patients. Methods: Renal scans of 89 subjects with 121 hydronephrotic renal units between January 2004 and March 2007 were identified and analyzed. Results: Of all renal units, 65% showed obstruction. GAD maneuver resulted in significant residual tracer drainage in eight renal units, moderate drainage in 12 renal units, and some improvement in 40 units after the GAD maneuver. Of the eight renal units with significant residual tracer drainage, only two proceeded to pyeloplasty. After pyeloplasty, nine children had improved time to half maximum (T 1/2 Max) and 13 were unchanged. Conclusions: Our study was limited due to its retrospective design and descriptive analyses, but includes a sufficient number of subjects to conclude that GAD as part of a diuretic renography protocol is an effective and simple technique that can help prevent unnecessary surgical procedures in pediatric patients. IntroductionWith the adoption of antenatal sonography as a routine screening tool, early detection of hydronephrosis has increased.1,2 When pelvicaliceal system distention is detected, it often leads to further investigation, including diuretic renography. This imaging modality can help identify patients with ureteropelvic junction obstruction (UPJO) and compromised renal function.3 Early identification of significant UPJO allows for interventions such as pyeloplasty, which can improve kidney drainage and preserve renal function. Those patients with mechanical obstruction suggestive of UPJO on diuretic renography, significant flank pain, or recurrent urinary tract infections are often considered for pyeloplasty, particularly if there is evidence of decline in differential renal function (DRF) on serial diuretic renal scans. 4 Selecting which patients will benefit from pyeloplasty remains a challenge. There is a lack of standardized protocols for both performing and interpreting diuretic renography. Additionally, many centres image patients in the supine position, which may underestimate drainage compared to the upright position, where the effects of gravity can help facilitate drainage (Fig. 1). 5 MethodsThe present study was approved by the Research Ethics Board at the IWK Health Centre. Ultrasonography was used to identify the presence of hydronephrosis, after which patients were referred for diuretic renal scans. Diuretic renography involves serial imaging of an injected radioactive tracer as it is filtered or secreted within the kidney through to its excretion in urine. Each child received simultaneous intravenous injection of 5 MBq/kg Tc 99m mercapto-acetyl-triglycine (MAG-3) and 1 mg/ kg (to a maximum of 40 mg) of furosemide. After radiotracer injection, the patient is placed s...