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.

Histiocytic necrotizing lymphadenitis-also known as Kikuchi -Fujimoto disease (KFD)-is a rare disease of unknown etiology. It was first described independently by Kikuchi ' and by Fujimoto et al' in articles published

One of the observed complications in patients after intestinal transplantation is the occurrence of ulcers in the native or transplanted gastrointestinal tract. Previous reports have described the appearance of ulcers but have not described any systemic approach to accurately diagnose the etiology of the ulcer. We evaluated 112 intestinal transplantation patients at our institution, in which endoscopic examination identified ulcer formation in 11 patients. No common or defining demographic or clinical variables were found in the patients with ulcers. Biopsies were obtained from the ulcer edge as well as the intervening mucosa. The most common changes in the ulcers were compatible with post-transplant lymphoproliferative disorder (PTLD), acute rejection, and viral infections. These changes could occur simultaneously and retrospective analysis showed that ulcers could have concomitant etiologies. Endoscopically directed biopsies of ulcer edges often displayed morphologic changes compatible with acute rejection of the graft. Some patients were treated for rejection based on the changes within the mucosa outside the ulcer bed, and they responded with resolution of the ulcers. Our findings demonstrate that PTLD and acute rejection are the most common causes of chronic ulcer formation and reinforce the concept that biopsy samples should be collected simultaneously from both the ulcer edge and intervening mucosa.