[Hemolytic uremic syndrome: long term renal injury]

Hemolytic uremic syndrome (HUS) is the most frequent cause of non-pre-renal acute renal failure in pediatrics and it is usually secondary to acute infectious diarrhea, generally due to Shiga-toxin producing E. coli. It is characterized by acute renal failure, hemolytic anemia and thrombocytopenia. It can lead to renal sequels in the long term and to end-stage renal disease.

The aim of this retrospective study is to describe and analyze renal sequels and their prognostic factors in pediatric patients suffering from HUS in a Spanish tertiary hospital during the last 28 years.

43 children with this condition were admitted, with 38 of them having presented with diarrhea previously. Among those with a follow-up longer than 3 months, 21.6% (8/37) had a reduction in glomerular filtration rate (GFR) in the last visit. Including proteinuria and hypertension, we found up to 35.1% (13/37) prevalence of chronic kidney disease, with 8.1% (3/37) of the patients with end-stage renal disease. We found the following to be prognostic factors for renal injury in the long term in a univariate logistic regression: hypertension, a longer stay in the hospital, more prolonged anuria, more severe leukocytosis and lower GFR at discharge. Multivariate logistic regression showed an association with time in anuria.

Approximately one third of our cases of hemolytic uremic syndrome developed some degree of chronic kidney disease in the long term. A deeper and longer initial renal disfunction is associated with a higher probability of subsequent renal problems.