Long-Term LN Prognosis Worse With Crescents

Studies have shown that the formation of cellular and fibrocellular crescents have a negative impact on the prognosis of renal disease. In terms of lupus nephritis (LN), some research has been conducted to examine a correlation between the presence of crescents and adverse events. However, its contribution to renal disease prognosis remains unknown.

In a study published in the European Journal of Medical Research, Sishi Lin, MD, and colleagues wrote: “Based on the [International Society of Nephrology and the Renal Pathology Society 2018] pathological classification, we retrospectively investigated the clinical and pathological characteristics of [patients with LN] with or without cellular/fibrocellular crescents in renal tissue from our center, and analyzed their relationship with the prognosis of LN.”

Examining the Role of Crescents in LN Severity & Activity

The researchers developed a single-center, retrospective cohort study to examine the role of crescents in the severity and activity of LN. The study identified 401 patients with LN from December 2001 to November 2017. After exclusion criteria were applied, including age and missing data, 296 patients were included in the study and divided
into two groups based on the presence or absence of cellular/fibrocellular crescents.

The crescent classification was identified along with activity index (AI) and chronic index (CI) of renal tissue. Baseline information and demographics were also collected. The composite endpoint was a decrease in estimated glomerular filtration rate (eGFR) of more than 30%, end-stage renal disease (ERSD) or the need for dialysis and/or
kidney transplantation, and death.

The researchers reported no significant demographic differences between the crescent and non-crescent groups. The crescent group had higher myelin basic protein (MBP; P<0.001), serum creatinine (P<0.001), white blood cell
(WBC) count (P=0.019), 24-hour proteinuria (P<0.001), urinary albumin-creatinine ratio (ACR; P<0.001), urine WBC count (P<0.001), urine red blood cell (RBC) count (P<0.001), the proportion of positive anti-double-stranded
DNA antibodies (P<0.001), and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) (P<0.001) compared with the non-crescent group.

The crescent group also had lower eGFR (P<0.001), serum albumin (P=0.001), hemoglobin (P<0.001), complement C3 (P=0.007), complement C4 (P=0.015), and lupus anticoagulant ratio (P<0.001) when compared with the non-crescent groups (Table).

There was no significant difference in endpoint events between the non-crescent and crescent groups (14.4% vs 22.0%), which may have been due to a shorter follow-up time in the crescent group compared with the non-crescent group. However, those patients followed for more than 3 months were shown to have a worse overall long-term prognosis in the crescent group (P=0.005).

Significant Interaction Between Crescents & Proteinuria Levels

Researchers noted a significant interaction between the presence of crescents and proteinuria levels at baseline, which was related to LN outcomes (P=0.006). Patients with different levels of proteinuria were treated differently, so the researchers further divided 24-h proteinuria into two levels: less than 3.5 g/24 h and equal to or more than
3.5 g/24 h.

This stratified analysis showed that the prognosis of LN in the group with proteinuria of less than 3.5 g/24 h and crescents was significantly worse than that in the group without crescents (P<0.001). There was no significant correlation between crescents and prognosis in the groups with proteinuria equal to or more than 3.5 g/24 h.

Dr. Lin and colleagues observed that their findings were not entirely consistent with prior studies. “Our study showed that patients with crescents in renal tissue had more severe and active disease manifestations, such as higher serum creatinine, lower serum albumin, higher SLEDAI, and higher AI score,” they wrote. “The long-term prognosis for patients with crescents was worse than that of patients without crescents.”