Empyema Due to Thoracic Migrating Appendicolith.

BACKGROUND: Retained appendicolith following appendicectomy, and can cause recurrent abscess in the abdomen and retroperitoneum. CASE CHARACTERISTICS: 11-yr-old boy who presented with subpulmonic abscess and pneumonia following appendicectomy for perforated appendicitis. OBSERVATION: Thoracotomy revealed a thick walled subpulmonic abscess surrounding an appendicolith along with a rent in the posterolateral aspect of the diaphragm. MESSAGE: In children presenting with pus collections and a history of recent appendicectomy, the possibility of a migrating appendicolith should be considered.