Crescents proportions above 10% are associated with unfavorable kidney outcomes in IgA nephropathy patients with partial crescent formation

Abstract

Purpose

Whether different crescentic proportions determine the progression of IgA nephropathy (IgAN) with crescents in less than 50% of glomeruli remains controversial. We aimed to evaluate the relationship between different proportions of crescents and kidney outcomes in IgAN with partial crescent formation.

Methods

Patients diagnosed as IgAN, having at least two crescents and in less than 50% of glomeruli, were categorized into three groups: Group I (crescents in ≤10% of glomeruli), Group II (10%< crescents ≤25% of glomeruli) and Group III (crescents >25% of glomeruli). Baseline clinicopathological parameters were evaluated. The kidney endpoint was a composite of a ≥ 40% decline in the initial estimated glomerular filtration rate, end-stage kidney disease, and kidney disease-related death.

Results

Of 183 IgAN patients with crescents in less than 50% of glomeruli, baseline 24-hour urinary protein and immunosuppressive treatment varied among the three groups (p < 0.05). During a median follow-up of 57 months (interquartile range 28–86), 50 (27.3%) patients reached the composite outcome. Kaplan–Meier survival analysis revealed that kidney survival in Group II (p = 0.049) and Group III (p = 0.008) was significantly shorter than in Group I, with no significant difference between Group II and III (p = 0.2). After adjusting for clinical factors and MEST score based on the multivariate Cox regression analysis, a crescent proportion >10% (HR = 3.431, 95% CI 1.067–11.03, p = 0.039) was predictive of time to unfavorable kidney outcome, with model adjustments improving predictability (c-index: 0.817).

Conclusion

The proportion of crescents reaching 10% of glomeruli in IgAN was identified as an independent risk factor for kidney survival.

Keywords:

• IgA nephropathy
• crescent
• clinicopathological characteristics
• prognosis

Author contributions

Dingxin Di conceived the idea and was a major contributor to manuscript writing. Lin Liu and Ying Wang conducted the data collection. Yue Yang and Shimin Jiang performed all statistical analyses and were involved in writing the manuscript. Shimin Jiang and Wenge Li critically revised the manuscript. All authors have read and approved the final manuscript.

Ethics approval

This study was approved by the institutional ethics committee of China-Japan Friendship Hospital.

Patient consent

Written informed consent for renal puncture was obtained from all the patients preoperatively. All patient data were deidentified for this study. The need for written informed consent was waived by the ethics committee of China-Japan Friendship Hospital due to retrospective nature of the study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

All data generated or analyzed during this study are included in this published article.

Additional information

Funding

This study was supported by the grant from National Key Clinical Specialty Capacity Building Project (2019-542).