Urinary sediment predicts active proliferative glomerular diseases.

Area of Science:

• Nephrology
• Urology
• Pathology

Background:

• Urinary sediment (U-sed) examination is valuable for diagnosing glomerular diseases (GD).
• A standardized U-sed approach may differentiate proliferative GD (PGD) from non-proliferative GD (NPGD).
• This study aimed to predict PGD with high activity scores on renal biopsy (RB).

Purpose of the Study:

• To evaluate the efficacy of standardized urinary sediment analysis in distinguishing PGD from NPGD.
• To determine if U-sed findings can predict a high activity score in renal biopsy for glomerular diseases.
• To compare the diagnostic performance of U-sed analysis with traditional urine reagent strips and clinical variables.

Main Methods:

• Prospective analysis of U-sed from 285 patients with biopsy-proven GD (172 PGD, 113 NPGD).
• Evaluation of red blood cells (RBC), white blood cells (WBC), renal tubular epithelial cells (RTEC), and casts in U-sed.
• Comparison of U-sed findings with reagent strip results (U-Hb, U-LE) and renal biopsy histological scores.

Main Results:

• Patients with PGD showed higher frequencies of RBC, WBC, RTEC, and RBC casts compared to NPGD.
• U-sed analysis, particularly RBC and WBC counts, demonstrated high predictive value (AUC 0.86 and 0.83).
• Combined U-sed parameters, including RTEC and RBC casts, achieved an AUC of 0.90, outperforming clinical variables (AUC 0.84) and reaching 0.96 when combined.

Conclusions:

• Standardized urinary sediment examination is a powerful tool for predicting proliferative glomerular disease.
• U-sed analysis significantly aids in identifying patients with high disease activity on renal biopsy.
• This non-invasive method offers superior diagnostic capability compared to traditional urine tests and clinical parameters alone.