A 52-year-old previously healthy man was admitted to the hospital with haematuria, painful micturition and fever. Laboratory investigation showed the presence of a haemolytic uraemic syndrome (HUS), characterized by haemolysis, renal insufficiency and mental disturbances. A urinary tract infection caused by a verotoxin-producing E. coli other than O157:H7 was diagnosed. Treatment of this infection resulted in his complete recovery from the illness. Both the search for a focus outside the gastrointestinal tract and the search for verotoxin genes by specific polymerase chain reaction can be crucial in a patient with HUS without preceding diarrhoea.