Hemolytic Uremic Syndrome (HUS)
The hemolytic uremic syndrome (HUS) is defined as a triad of acute kidney failure, thrombocytopenia and hemolysis with fragmentocytes. The most common HUS entity is the enteropathogenic EHEC-associated HUS. In 5 to 10 % of the children (2 to 5 years old) ca. 7 days after the diarrhea started the HUS occurs. Of these, approximately two third require dialysis due to renal failure. Chronic sequelae of the enteropathogenic HUS comprise chronic kidney failure, arterial hypertension, endocrine and exocrine pancreatic insufficiency or neurological dysfunctions.
Besides the patient's age and yet unknown host factores the virulence make-up is crucial for the development of extraintestinal manifestations.
Using different subtyping approaches, we aim for a better risk assessment whether a patient infected with EHEC will develop HUS.
Although the majority of EHEC are susceptible against antibiotics, at least during the early phase of an EHEC infection (diarrhea) antibiotics are not recommended. It was shown that subinhibitory amounts of antibiotics induce the production and release of Shiga toxins. This increases the risk to develop a more severe course of infection with a higher rate of extraintestinal manifestations. Therefore, an antibiotic therapy that is necessary because of an EHEC-indepentent infection (e.g. pneumonia) has to be considered very carefully.
Currently, only symptomatic therapy is recommended emphasizing the need of kidney protection. In cases of atypical courses of infection (especially in extrarenal HUS manifestations) sometimes antibodies against v. Willebrand-cleavage-factor were determined. In such cases, plasmapheresis seemed to be beneficial.
Due to the lack of specific therapeutic options, prevention of the spread of EHEC is of utmost importance, such as correct handling of food including production and transportation and correct hygiene/infection control measures in the surroundings of EHEC patients.