PYT Chan, MHK Ho, DKL Cheuk, TL Lee, SY Ha, YL Lau

Abstract

Haematopoietic stem cell transplantation is a curative therapy for severe combined immunodeficiency (SCID) after the first success forty years ago. We report a pair of Chinese siblings with X-linked SCID who had very different transplant outcomes. The elder brother was diagnosed late and had multiple infections before transplant. He developed severe graft-versus- host- disease and life-threatening haemolytic anaemia. He died from overwhelming septicaemia. The younger brother, who was diagnosed at birth and infection-free before transplant, underwent an uneventful transplant. Early transplant within the first 3 months of life results in over 90% disease-free survival. Newborn screening is now being pursued to achieve this goal.