Predictors of mortality in children with lupus nephritis

Abstract

Background Renal involvement during the clinical course of
systemic lupus erythematosus (SLE) is generally considered to be
the most important factor influencing disease prognosis in terms
of morbidity and mortality. Various factors have been reported to
influence the prognosis of lupus nephritis (LN).
Objective To analyze clinical signs and laboratory parameters that
might serve as predictors associated with mortality in pediatric
LN.
Methods Retrospectively, medical records of children with LN
at Soetomo Hospital from 1998 to 2011 were studied. Diagnosis
of SLE was based on Revised American Rheumatism Association
critera, while patients with clinical manifestations of hypertension,
abnormal urinalysis, and serum creatinin > 1 mg/dL were
considered as lupus nephritis. Cox proportional hazard modeling
was used to assess for associations of clinical signs and laboratory
parameters with mortality. Kaplan-Meier survival analysis was
used to assess the cumulative survival from the time of diagnosis
to the outcome.
Results There were 57 children with LN of whom 43 (75%) were
girls. The female-to-male ratio was 3:1. Subjects’ mean age was 10.6
(SD 6.87) years. The mean time of observation was 51 (SD 74.54)
months and 23 (40%) children died. Age, gender, hypertension,
hematuria, proteinuria, and anemia were not significant as
predictors for mortality. However, hypertensive crisis (HR=2.79;
95%CI 1.16 to 6.75; P=0.02) and initial glomerular filtration rate
(GFR) of <75 mL/min/1.73m2 (HR=3.01; 95%CI 1.23 to 7.34;
P=0.01) were significant predictors of mortality in children with LN.
The mean survival time of LN with hypertensive crisis and initial
GFR <75 mL/min/1.73m2 was 36.9 (SD 12.17) months.
Conclusion Hypertensive crisis and GFR <75 mL/min/1.73m2 are
significant predictors of mortality in children with LN.