CLINICAL AND HISTOPATHOLOGICAL SPECTRUM OF KIDNEY BIOPSIES OF PATIENTS PRESENTING AS RAPIDLY PROGRESSIVE RENAL FAILURE (RPRF) – A SINGLE CENTRE OBSERVATIONAL STUDY

8 Feb 2025 12 a.m. 12 a.m.

WCN25-AB-186, Poster Board= SAT-128

Introduction:

Rapidly progressive renal failure (RPRF) is a clinical diagnosis when patient presents with rapid and progressive decline in the glomerular filtration rate (GFR) of at least 50% over a short period, ranging from days to weeks. However, KDIGO has suggested a new operational terminology of acute kidney disease (AKD) when renal impairment duration is ≤ 3 months. Important differential diagnoses of RPRF include vasculitis (systemic or renal-limited), primary glomerular disease like Lupus nephritis, plasma cell dyscrasia, thrombotic microangiopathy and acute interstitial nephritis. Early definitive diagnosis of RPRF is essential as majority etiologies are potentially reversible with available effective treatment options.

Methods:

This retrospective observational study was done in the Department of Nephrology at a tertiary care corporate hospital situated in Northern part of India. All native kidney biopsies performed at our center from July 1, 2023 to June 30, 2024 were reviewed.

Results:

During this period total of 310 real time ultrasonography guided kidney biopsies were performed, out of which 202 were native kidney biopsies and rest were graft biopsies. 25 native biopsies with history suggesting of RPRF like clinical presentation were analyzed in detail. Mean age of patients presenting as RPRF was 54.04 ± 15.26 years and male to female ratio was 17:8. Mean serum creatinine at the time of kidney biopsy was 5.84 ± 2.94 mg/dl. 80 % patients had microscopic hematuria on presentation. Mean protein creatinine ratio was 2050 ± 1150 mg/g. Almost 50 per cent of patients had hypertension as comorbidity, while only 16 % had diabetes.

The most frequent histological diagnosis was pauci-immune glomerulonephritis (32%) followed by interstitial nephritis (20%) and IgA nephropathy (16%). Interestingly, one patient each of collagenofibrotic glomerulopathy and C3GN also had RPRF like presentation.

	Value (Percentage)
Total Kidney Biopsy done during study period	310
Native Kidney Biopsy (excluding graft biopsy)	202
Biopsies with RPRF like presentation	25 (12.37%)
Mean Age (years)	54.04 ± 15.26
Male : Female	17 : 8
Mean Serum Creatinine at the time of Biopsy (mg/dl)	5.84 ± 2.94
Mean Protein Creatinine Ratio at the time of Biopsy (mg/g)	2050 ± 1150
Presence of Hematuria	20 (80%)
Comorbidity Hypertension Diabetes Mellitus	12 (48 %) 4 (16%)

Conclusions:

Rapidly progressive renal failure (RPRF) is a clinical diagnosis which is synonym with rapidly proliferative glomerulonephritis (RPGN). Acute kidney disease (AKD) is newer operational terminology for similar presentations. This study is an attempt to provide information about clinical and histopathological spectrum of RPRF, and importance of kidney biopsy to make early and definitive diagnosis, thus preventing progression to chronic kidney disease. Though, rapidly progressive renal failure is unusual in IgA nephropathy, but this small study done over limited time, highlights IgA nephropathy as third most common cause preceded just by pauci-immune glomerulonephritis and interstitial nephritis.

I have no potential conflict of interest to disclose.

I did not use generative AI and AI-assisted technologies in the writing process.