Venous thrombosis is a complication that mostly occurs in the paediatric patient with multiple comorbidities. In these cases, it is relatively simple for the paediatrician to suspect the presence of a thrombosis. On the contrary, due to the rarity of the pathology and the clinical presentation that can mimic other conditions, it could be difficult to recognize a thrombotic event in an extra-hospital context and in an "otherwise healthy" child. This article aims to examine how to diagnose and treat this rare paediatric condition promptly