Aim: To evaluate phase-contrast microscopy in differential diagnosis of asymptomatic microhematuria in patients with asymptomatic microhematuria during the 1993-2000 period.
Patients and methods: The study was performed at the Laboratory of Cytology, Department of Nephrology and Dialysis, Rijeka University Hospital Center, Rijeka, Croatia, and included 526 patients with asymptomatic hematuria referred from Urology Department.
Main outcome measures: Presence of red blood cells (RBC), other cell types, other elements, and detritus. According to size and shape, RBCs were classified into 2 main categories: dysmorphic and isomorphic RBCs. The presence of > 80% of dysmorphic RBCs was recognized as glomerular hematuria. Isomorphic cell predominance was classified as postglomerular hematuria, and equal presence of both types was considered as mixed hematuria.
Results: Glomerular hematuria was found in 238 (45.2%), postglomerular hematuria in 181 (34.4%) and mixed hematuria in 22 (4.2%) patients. Additional diagnostic procedures in patients with glomerular hematuria included renal biopsy. In 89% of those patients glomerular disease was found.
Conclusion: Phase-contrast microscopy is a simple, noninvasive and reliable diagnostic procedure in nephrology practice.