Haemolytic uraemic syndrome during shigellosis

Haemolytic uraemic syndrome (HUS), which is comprised of the triad of haemolytic anemia, thrombocytopenia and renal insufficiency, occurs in about 13% of dysenteric patients with shigellosis due to Shigella dysenteriae type 1 (SD1) infections, who are mostly children less than five years old in Africa and Asia. With a case-fatality rate of about 36%, it is the leading cause of death in SD1 outbreaks. Research suggests that Shiga toxin and lipopolysaccharide from the causative bacteria play roles in pathogenesis. The risk of HUS is increased when inappropriate antimicrobial drugs, against which infecting bacteria are resistant, are used or when any antimicrobial drug is given more than four days after the start of diarrhoea. To prevent HUS, it is advised to initiate an appropriate drug early and to consider withholding antimicrobial therapy in patients presenting more than four days after the onset of diarrhoea.