Evaluation of Urine Phase Contrast Microscopy and Renal Biopsy in Differentiating Glomerular and Non-Glomerular Haematuria in Patients With Kidney Disease

Abstract

Introduction: Haematuria is one of the most common presentations of renal disease Urinary sediment examination by urine phase contrast microscopy (PCM) is a useful diagnostic marker for glomerular bleeding if correctly interpreted and used. Although PCM is simple and cost effective the percentage of dysmorphic red cells regarded as diagnostic of glomerular haematuria is controversial and varied from (10-90)% cases in different series. This study is done with the aim to evaluate urine phase contrast microscopy as a tool
in differentiating glomerular haematuria in patients with glomerulonephritis confirmed by renal biopsy and non-glomerular haematuria in patients with renal stone disease.

Materials and Methods: In this study, 175 patients with haematuria were taken and were divided into two groups; Group I with diagnosed cases of glomerulonephritis with haematuria confirmed with renal biopsy and Group II with patients of renal stone disease with haematuria. After diagnosing haematuria, all patients were undergone for urine phase contrast microscopy. Renal biopsy was done in patients suspected for glomerulonephritis.

Results: This study showed that the mean percentage of dysmorphic RBCs in group I by urine PCM was (35.8%) which was significantly
higher than in group II (6.8%). A comparison was done between the different cut off values for percentages of dysmorphic RBCs to differentiate glomerular from non-glomerular haematuria. For a cut off value of 20%, the present study showed the most agreeable sensitivity 80.7% and specificity 90.6%.Receiver-operator characteristic curve for percentage of dysmorphic RBCs, area under the
curve was 0.934, which gave an optimal sensitivity 80.7% and specificity 90.6% for a decision level Evaluation of Urine Phase Contrast Microscopy and Renal Biopsy in Differentiating Glomerular. K C A et. al. ~340~˷ Original Article Medical Journal of Pokhara Academy of Health Sciences Vol. 4 Issue 1 cut off of 20% dysmorphic RBCs. It was found that patients of group I had higher serum creatinine
level (mean 1.6 mg/dl) in comparison to group II (mean 1.1mg/dl). Similarly patient of group I had higher level of proteinuria in comparison to group II. It was also ovbserved that patients  with proliferative glomerulonephritis had higher percentage of dysmorphic RBCs in comparison to non-proliferative type of glomerulonephritis.

Conclusion: Urine phase contrast microscopy is a simple, cost effective, non invasive and reliable investigation. Patients with proliferative glomrulonephritis may have a higher percentage of dysmorphic RBCs in comparison to those with non proliferative glomerulonephrits.