Lupus nephritis in an Afro-Caribbean population: renal indices and clinical outcomes

In an Afro-Caribbean population, 111 new cases of systemic lupus erythematosus were diagnosed in the 10-year period from January 1995. Fifty-three cases (48%) presented with or subsequently developed lupus nephritis (SLEN). We recorded clinical characteristics and treatment outcomes of SLEN. We retrospectively categorized patients into four groups based on presence or absence of proteinuria with or without renal impairment. Group 1 (n = 15, 28%) had normal renal function (creatinine clearance (CrCl) > 70 mL/minute) with urinary protein excretion (UPE) of 0.5-3.0 g/24 hour, group 2 (n = 7, 13%) had normal renal function with UPE > 3.0 g/24 hour, group 3 (n = 9, 17%) had renal impairment (CrCl < 70 mL/minute) with UPE of 0.5-3.0 g/24 hour and group 4 (n = 22, 42%) had renal impairment with UPE > 3.0 g/24 hour. Renal biopsies were performed in 15 patients (28%). The number of treated patients in-remission decreased across the groups, from 100% in group 1 and 71% in group 2, to 33% in group 3 and 32% in group 4 (Pr < 0.001). There were 12 deaths from renal causes: none in groups 1 and 2, two (22%) from group 3 and 10 (45%) from group 4 (Pr = 0.003). In resource-poor clinical settings with limited access to histopathological services, CrCl and UPE may be useful predictors of therapeutic response and clinical outcomes in SLEN.