Outcome 10 years after Shigatoxin-producing E. coli (STEC)-associated Hemolytic Uremic Syndrom: importance of long-term follow up

Abstract

Abstract Background Hemolytic uremic syndrome (HUS) is an important cause of acute kidney injury in children. HUS is known as an acute disease followed by complete recovery in most cases, but patients may still present kidney abnormalities after long periods of time. This study was performed to evaluate the long-term outcome of Shigatoxin-producing Escherichia coli-associated HUS (STEC-HUS) in pediatric patients, 10 years after the acute phase of disease and identify risk factors for long-term sequelae. Methods 619 patients under 18 years of age with HUS (490 STEC-positive, 79%) were registered in Austria and Germany over a 6-year period. The data of 138 STEC-HUS-patients was available after 10 years for analysis. Results Sixty-six% (n = 91, 95%CI0.57-0.73) of patients fully recovered showing no sequelae after 10 years. Thirty-four% (n = 47, 95%CI0.27-0.43) presented either with decreased glomerular filtration rate (24%), proteinuria (23%), hypertension (17%) or neurological symptoms (3%). Sixty-four% (n = 30) had sequelae 1 year after STEC-HUS, the rest presented sequelae unprecedented at the 2-year (n = 2), 3-year (n = 3), 5-year (n = 3) or 10-year (n = 9) follow-up. 17 patients (36.2%) without sequelae at 1-year follow-up presented kidney symptoms after a period of apparent total recovery, half of these (n = 9) between 5 and 10 years after STEC-HUS. Patients needing extracorporeal treatments during the acute phase were at higher risk of presenting symptoms after 10 years (p < 0.05). Conclusions Patients with STEC-HUS should be followed up regularly and for at least up to 10 years after the acute phase of disease, because long-term sequelae can still occur at that time. Characteristics that may help predict poor long-term outcome are an initial critical illness, marked by need of kidney replacement therapy or plasma treatment.