Kuala Lampur, April 22 -- As Malaysia joins the global community in observing World Primary Immunodeficiency Week from April 22 to 29, 2026, attention turns to a group of conditions that are often described as rare, but are more accurately understood as rarely recognised.

These disorders, now classified as Inborn Errors of Immunity (IEI), encompass more than 500 genetically defined conditions that impair the body's ability to defend itself against infections. At a clinical level, they are defects in the body's genetic blueprint. At a human level, they are often a quiet and prolonged struggle, marked by repeated illness, delayed diagnosis, and uncertainty.

In Malaysia, this struggle is compounded by a significant diagnostic gap. A system...