Lupus nephritis in Croatian children: clinicopathologic findings and outcome

We report clinical and histopathological features, treatment and outcome of 37 Croatian children with biopsy-proven lupus nephritis seen over a 30-year period. The mean age at lupus nephritis presentation was 12.11 ± 2.59 years (range 4.66-17.0). The most frequent histopathological finding was class IV (37.8%), followed by class III (35.1%), class V (16.2 %) and class II (10.8 %) lupus nephritis. Compared with other classes there were more boys among patients with class IV lupus nephritis, and hypertension, nephrotic syndrome and decreased estimated glomerular filtration rate at presentation were more common. The median histopathological activity and total scores were highest in class IV lupus nephritis patients. The mean follow-up was 7.14 ± 4.71 years, ranging from 1.1 years to 21.0 years. Kaplan-Meier estimate S: of patient and kidney (without renal failure) survival rate S: were 90.5% and 87 % at five years. The renal survival rate of class IV lupus nephritis patients was found significantly lower compared with other histological classes combined. Decreased estimated glomerular filtration rate at the time of diagnosis, class IV lupus nephritis versus other lupus nephritis classes, and high total histological score were the parameters significantly associated with adverse outcome. The therapy with cyclophosphamide showed as superior to the therapy with azathioprine.