Hemolytic uremic syndrome in children: Clinical characteristics and predictors of outcome

Background

Hemolytic uremic syndrome (HUS) is the most common thrombotic microangiopathy (TMA) occurring in children.

Objectives

To study the clinico-laboratory profile and identify the potential outcome predictors in children with hemolytic uremic syndrome.

Methodology

A retrospective observational study was conducted at a tertiary center in South India. Children diagnosed with HUS during the study period of 10 years were included. The demographic, clinical, and laboratory details, complications, and outcomes were recorded. Predictors of mortality were analyzed.

Results

Among 44 children with HUS, 14 (31.8 %) children were diagnosed with D + HUS while 30 had D-HUS. The median age at diagnosis was 6.3 years. Male preponderance (55.9 %) was observed. Presenting symptoms included oliguria in 36 (86.4 %), followed by fever, observed in 34 (77.3 %). 12 (27.2 %) children had anuria. Seizures and altered sensorium were present in 12 (27.35) and 16 (36.4 %) children respectively. Hypertension was observed in 33 (75 %) children. Plasmapheresis was performed in 18 (13.6 %) children. 17 (38.6 %) children underwent hemodialysis, and 7 (15.9 %) underwent peritoneal dialysis. The median duration of hospital stay was 18 (9.7, 27.7) days. Complications observed during the study were CNS involvement was seen in 16 (36.4 %) children, while coagulopathy was observed in 3 (6.8 %) children. Mortality was observed in 16 children (36.4 %). Anuria at admission was more prevalent in non-survivors (10 out of 16 children; p 0.003). The median albumin and C3 levels were significantly low in non-survivors (p-value <0.001 and 0.008 respectively). A total leucocyte count >15,000 X 10⁹ cells/L was independently associated with mortality even after adjustment with duration of symptoms before diagnosis >10 days and low C3 levels (adjusted OR [95 % CI]: 1.12 [1.02, 1.92] (p-value 0.03).

Conclusion

Hypoalbuminemia and hypocomplementemia were observed in higher proportions among non-survivors. Elevated leucocyte count at admission was an independent predictor of mortality.