The uncertain correlation of ANCAs in patients with lupus nephritis and crescents, an experience from Chinese centers.

BACKGROUND

The precise role of anti-neutrophil cytoplasmic antibodies (ANCAs) in the pathologic course of crescentic lupus nephritis (LN) remains unclear. Our study aimed to assess whether ANCA-positive serology in patients with LN and crescents is associated with different clinicopathologic features and outcomes.

METHODS

We reviewed the records of 658 patients diagnosed with LN between 2010 and 2022. Among them, 64 (9.7%) patients who had complete follow-up and clinical data were reclassified as crescentic glomerulonephritis. Of these, 11 patients with incomplete ANCA data and 7 patients with less than 10 glomeruli under light microscopy were excluded; ultimately, 46 patients were enrolled: 12 with ANCA positivity and 34 with ANCA negativity. Clinicopathological characteristics and outcomes were analysed and compared.

RESULTS

Our data did not reveal any differences in clinical or laboratory parameters or histopathological features except for a significantly higher level of proteinuria or proportion of nephrotic syndrome (p < 0.05) at presentation before biopsy in the ANCA-negative group than in the ANCA-positive group,and a lower level of serum albumin (p < 0.05) in the ANCA-negative group than in the ANCA-positive group. No significant differences in complete remission or partial response were detected between the two groups based on the 2021 KDIGO criterion.

CONCLUSION

Short-term follow-up (average follow-up time of less than 3 years) did not reveal any difference in outcomes between ANCA-positive and ANCA-negative crescentic LN. However, the role of ANCAs in the pathological course of crescentic lupus nephropathy and the effect of ANCAs on long-term outcomes remain to be determined.