Early-stage predictors for treatment responses in patients with active lupus nephritis.

OBJECTIVE: We analyzed data of lupus nephritis (LN) patients to find parameters that can predict remission.

METHODS: Sixty-four LN patients who were diagnosed with class III, IV, V or V + III/IV by renal biopsy and were followed up for more than six months in our center were enrolled retrospectively. Receiver operating characteristic curves were used to test the predictive values of urinary protein-to-creatinine ratio (UPCR), serum albumin and complement C3 at the first, second and third months as predictors for remission at the sixth month.

RESULTS: The patients' renal pathologies were class III (five cases), class IV (33 cases), class V (nine cases) and class V + III/IV (17 cases). All patients received standard immunosuppressive therapy. Forty-six (71.9%) patients (grouped as the remission group) achieved remission at the end of the sixth month, including 23 complete remissions and 23 partial remissions. The other 18 patients were grouped as the no-remission group. There were no significant differences in clinical data, proportion of immunosuppressive therapy or renal pathological characteristics between the remission group and no-remission group at baseline, except the serum urea nitrogen of the remission group was lower than in the no-remission group. The UPCR were significantly lower in the remission group than in the no-remission group at months 1, 2, 3 and 6, respectively, while the serum albumin was significantly higher in the remission group than in the no-remission group at months 3 and 6, respectively. There were no significant differences in serum creatinine between the remission group and no-remission group, except at month 1. The C3 levels were higher in the remission group than in the no-remission group at months 1, 2 and 3, respectively. The areas under the curve (AUC) of the change percentage of UPCR at month 3 and the serum albumin at month 3 were the most significant (AUC 0.778, p = 0.002; AUC 0.773, p = 0.001, respectively). The cutoff value of the change percentage of UPCR at month 3 was 59%. The cutoff value of serum albumin at month 3 was 32.9g/l.

CONCLUSION: The change percentage of UPCR ≥59% and the serum albumin ≥32.9 g/l at the third month were valuable for predicting remission at the sixth month in LN. Because of the small-size and retrospective nature, this study needs to be validated.