Kidney Week

Abstract: FR-PO885

Nonalbumin Protein-to-Creatinine Ratio in IgA Nephropathy: Clinical and Pathological Correlations

Session Information

• IgA Nephropathy: Clinical, Outcomes, and Therapeutics
  October 25, 2024 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Glomerular Diseases

• 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics

Authors

• Kanzaki, Go, Tokyo Jikeikai Ika Daigaku, Minato-ku, Tokyo, Japan

Go Kanzaki, MD, PhD

• Shimoyama, Kotaro, Tokyo Jikeikai Ika Daigaku, Minato-ku, Tokyo, Japan

Kotaro Shimoyama, MD

• Kuno, Hideaki, Tokyo Jikeikai Ika Daigaku, Minato-ku, Tokyo, Japan

Hideaki Kuno

• Hatanaka, Saeko, Tokyo Jikeikai Ika Daigaku, Minato-ku, Tokyo, Japan

Saeko Hatanaka, MD

• Marumoto, Hirokazu, Tokyo Jikeikai Ika Daigaku, Minato-ku, Tokyo, Japan

Hirokazu Marumoto, MD

• Sasaki, Takaya, Tokyo Jikeikai Ika Daigaku, Minato-ku, Tokyo, Japan

Takaya Sasaki, MD

• Haruhara, Kotaro, Tokyo Jikeikai Ika Daigaku, Minato-ku, Tokyo, Japan

Kotaro Haruhara, MD, PhD

• Koike, Kentaro, Tokyo Jikeikai Ika Daigaku, Minato-ku, Tokyo, Japan

Kentaro Koike, MD, PhD

• Ueda, Hiroyuki, Tokyo Jikeikai Ika Daigaku, Minato-ku, Tokyo, Japan

Hiroyuki Ueda, MD, PhD

• Tsuboi, Nobuo, Tokyo Jikeikai Ika Daigaku, Minato-ku, Tokyo, Japan

Nobuo Tsuboi, MD, PhD, FASN

• Yokoo, Takashi, Tokyo Jikeikai Ika Daigaku, Minato-ku, Tokyo, Japan

Takashi Yokoo, MD, PhD

Background

Although albuminuria is beneficial for the early detection of kidney disease, it is insufficient for the characterization of tubular and hyperfiltration proteinuria. This study evaluated the non-albumin protein-to-creatinine ratio (NAPCR) in patients with IgA nephropathy, from both clinical and pathological perspectives.

Methods

This study included 59 patients diagnosed with IgA nephropathy via kidney biopsy at our hospital between June 2022 and November 2023. NAPCR (g/gCr) was determined by subtracting urinary albumin (ACR) from urinary protein (PCR). The clinical grade (C-grade) of IgA nephropathy at the time of biopsy was assessed according to the criteria of the Japanese Society of Nephrology (JSN) criteria. Histological severity was classified based on the JSN histological grading criteria or the Oxford classification. Risk stratification for dialysis was determined by combining clinical and histological grades (H-grade) according to the JSN and categorized into low, medium, high, or super-high risk of progression to end-stage kidney disease (ESKD).

Results

he average age of the patients was 48 years (31 males, 53.4%). The mean estimated glomerular filtration rate (eGFR) was 56.3 ml/min/1.73m^{<span style="font-size:10.8333px">2</span>}. The average PCR was 0.51 g/gCr, and the ACR was 0.35 g/gCr. Higher NAPCR values correlated with increased clinical and histological severity (Table), whereas PCR did not correlate with histological severity.

Conclusion

NAPCR was significantly associated with clinical and histological severity of IgA nephropathy.