We present the case of a three-day-old newborn, who came to the emergency department with his mother because of an enlargement of the left hemiscrotal and a purplish colour; the newborn was well at birth according to the parents, and in the last four hours he had been crying inconsolably.

There was no fever or other clinical findings. On examination there was an enlarged left hemiscrotal, painful on manipulation, and wine-red in colour.

Laboratory tests showed no abnormalities in the haemogram, biochemistry or coagulation studies.

Scrotal ultrasound showed a normal right testicle; the left testicle was found to be enlarged, with irregularities in its interior, with an anechoic area that may suggest necrosis, surrounded by a hyperechoic area suggestive of calcification; all of this was compatible with advanced testicular torsion.

The patient underwent surgery and the left testicle was removed and the right testicle was fixed, evolving favourably and two years later he was well and the right testicle was normal in size and consistency.