We report acute appendicitis presenting as acute urinary retention in a 3½ year old boy, admitted with a four day history of central abdominal pain associated with diarrhoea but no urinary symptoms. He was apyrexial, hydrated, with mild tenderness in the suprapubic region. He developed dysuria and went into acute urinary retention confirmed by an ultrasound scan that also showed moderate hydronephrosis. Passage of a urethral catheter relieved his symptoms and when, 12 hours later the catheter fell out, he was able to pass 175 ml of urine spontaneously.

The child was transferred to the care of a paediatric urologist at …