Cytodiagnostic urinalysis. Three years experience with a new laboratory test

Area of Science:

• Urology
• Nephrology
• Pathology

Background:

• Traditional urinalysis may lack sensitivity in detecting subtle renal parenchymal disease.
• Cytodiagnostic urinalysis using Papanicolaou-stained urine sediment offers a potential improvement.
• Evaluating nonrenal transplant patients provides a generalizable dataset for renal health assessment.

Purpose of the Study:

• To assess the diagnostic utility of cytodiagnostic urinalysis in identifying renal parenchymal abnormalities.
• To determine the sensitivity of Papanicolaou-stained urine sediment examination for detecting hematuria, white blood cell casts, and renal tubule cell injury.

Main Methods:

• Review of cytodiagnostic urinalysis results from 1,602 nonrenal transplant patients.
• Examination of Papanicolaou-stained cytocentrifuge preparations of urine sediment.
• Quantification of specific urinary sediment findings, including renal hematuria, white blood cell casts, and renal tubule cells.

Main Results:

• Renal hematuria was identified in 37.7% of specimens.
• White blood cell casts were present in 11% of samples.
• Evidence of renal tubule cell injury was observed in 53% of cases.

Conclusions:

• Cytodiagnostic urinalysis demonstrates significantly enhanced sensitivity for detecting urine sediment abnormalities indicative of renal parenchymal disease.
• The technique is technically feasible, readily implementable in standard laboratories, and requires a short learning curve for personnel.
• This method offers a valuable tool for the early detection and assessment of kidney disease.