RESUMEN
BACKGROUND: Usually, a virus is the cause of gastroenteritis in children. If the diarrhoea persists for a long time or the course is atypical, another causative agent may be the cause. CASE DESCRIPTION: We present the case history of a 15-month-old boy with atypical gastroenteritis in which he had prolonged diarrhoea and vomiting. We found a cryptosporidium as the causative agent. CONCLUSION: Especially young children, the elderly, patients with IgA deficiency or other immune disorders are at risk of severe and prolonged diarrhoea with dehydration caused by cryptosporidium. The disease is self-limiting but can sometimes become chronic. In the Netherlands no medical treatments are available. Farm animals and surface water are the main reservoirs of cryptospores. Because the sporozoites are resistant to chlorine and alcohol, elimination is difficult.