During holidays in Suriname a six year old boy fell ill with high fever, general malaise, pain in the extremities and abdomen and vomiting. Because of a tentative diagnosis of acute rheumatism or bacterial enteritis amoxicillin and salicylates were started. After his return to the Netherlands an increased ESR and impaired renal and hepatic functions were found. The history revealed contact with sewage water. Further analysis established the diagnosis of Leptospirosis. This comparatively rare clinical entity, seldom mentioned in paediatric literature, is discussed.