Kidney Week

Abstract: FR-PO655

Clinicopathological Characteristics of the Pediatric IgA Nephropathy with eGFR <90 mL/min/1.73 m2 at Onset

Session Information

• Pediatric Nephrology - II
  November 03, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Pediatric Nephrology

• 1900 Pediatric Nephrology

Authors

• Shima, Yuko, Wakayama Kenritsu Ika Daigaku, Wakayama, Wakayama, Japan

Yuko Shima,

• Mukaiyama, Hironobu, Wakayama Kenritsu Ika Daigaku, Wakayama, Wakayama, Japan

Hironobu Mukaiyama,

• Tanaka, Yu, Wakayama Kenritsu Ika Daigaku, Wakayama, Wakayama, Japan

Yu Tanaka,

• Shimabukuro, Wataru, Ryukyu Daigaku Igakubu Daigakuin Igaku Kenkyuka, Nakagami-gun, Okinawa, Japan

Wataru Shimabukuro,

• Kaito, Hiroshi, Hyogo Kenritsu Kodomo Byoin, Kobe, Hyogo, Japan

Hiroshi Kaito,

• Tanaka, Ryojiro, Hyogo Kenritsu Kodomo Byoin, Kobe, Hyogo, Japan

Ryojiro Tanaka,

• Nozu, Kandai, Kobe Daigaku Daigakuin Igakukei Kenkyuka Igakubu, Kobe, Hyogo, Japan

Kandai Nozu,

• Iijima, Kazumoto, Kobe Daigaku Daigakuin Igakukei Kenkyuka Igakubu, Kobe, Hyogo, Japan

Kazumoto Iijima,

• Tokuhara, Daisuke, Wakayama Kenritsu Ika Daigaku, Wakayama, Wakayama, Japan

Daisuke Tokuhara,

• Yoshikawa, Norishige, Shakai Iryo Hojin Aijinkai Takatsuki Byoin, Takatsuki, Osaka, Japan

Norishige Yoshikawa,

• Nakanishi, Koichi, Ryukyu Daigaku Igakubu Daigakuin Igaku Kenkyuka, Nakagami-gun, Okinawa, Japan

Koichi Nakanishi,

Background

The pediatric IgA nephropathy (IgAN) cases with eGFR<90 ml/min/1.73m² (eGFR<90) at onset are regarded as a type of severe case in the Japanese Clinical Practice Guidelines for Pediatric IgA Nephropathy 2020. However, clinicopathological characteristics of those patients are not clarified. So, the purpose of this study is to clarify the clinicopathological features of those with eGFR<90 at onset.

Methods

From July 1976 to December 2018, among 560 children with biopsy-proven IgAN at Kobe University and Wakayama Medical University, Cr-eGFR at onset was available in 555. We investigated clinicopathological differences in 107 (19.3%) patients with eGFR<90 at onset and the other 448 patients.

Results

About 30% of eGFR<90 cases were detected as with gross hematuria. And there were significant differences in the proportion of boys (69.2 vs. 51.8%, p=0.001), onset age (9.6 vs. 11.0 years, p<0.0001), the prevalence of nephrotic syndrome (10.3 vs. 4.9%, p=0.004), proteinuria (1.2 vs. 0.9 g/gCr, p=0.03), and renal biopsy before 1990 vs. after 1990 (73.8 vs. 33.7%, p<0.0001). There was no significant difference in pathological findings. The renal survival rate in the eGFR<90 group was significantly lower (77.9 vs. 93.3% at 15 years; 95%CI: 53.3-91.6 vs. 83.8-97.0%, p=0.006). In patients with eGFR<90 at onset, when irreversible eGFR<60 state is defined as kidney failure, the patients who progressed to kidney failure showed lower eGFR at onset (64.7 vs. 78.2 ml/min/1.73m2, p=0.0001), heavier proteinuria (2.6 vs. 1.0 g/gCr, p=0.008), and no remission of proteinuria after treatment (0.0 vs. 52.6%, p=0.001).

Conclusion

Cases with eGFR<90 at onset are clinically severe cases with various histopathological features, and some of them do not respond to treatment and have poor renal prognoses.