Long-term follow-up of children with typical hemolytic uremic syndrome

Objective: The aim of the study was to determine the associations of the acute period course with late-emerging sequelae in children with typical hemolytic uremic syndrome (HUS).

Materials and methods: The data of 62 children with typical HUS during the acute phase were retrospectively analyzed by age, sex, duration of anuria/oliguria, method and duration of renal replacement therapy, proteinuria, hypertension, and renal function. The data of 33 children at 10-year follow-up after the onset of the disease were evaluated for changes in hypertension, proteinuria, and renal function.

Results: In the acute phase of the disease (n=62), hypertension was documented in 75.8% of the children; proteinuria, in 85.5%; and renal dysfunction, in 100%. At 10 years after the onset of the disease (n=33), hypertension was documented in 12.1%, 6.1%, and 24.2% at 1-, 5-, and ≥10-year follow-ups, respectively, and more often in children aged <1 year at the onset of the disease. Proteinuria was found in 15.2%, 9.1%, and 33.3% of the patients, respectively. After ≥10 years, hypertension developed for the first time in 6.1% of the patients. Renal injury of varying degrees was seen in 15.2% of the children at the 1-year follow-up, and after ≥10 years the proportion increased to 33.3%.

Conclusions: At 10 years after the acute phase of typical HUS in children, the prevalence of hypertension and proteinuria at 1- and 5-year follow-ups decreased, but after 10 years it started to increase. As much as 6.1% of the children developed hypertension or proteinuria for the first time at 10 years. Hypertension was documented more frequently in children who were younger than <1 year at the onset of the disease. Renal dysfunction after 5 and 10 years remained in more than one-third of cases, and it was observed more often if hypertension was documented at the acute period.