Advances in the diagnosis and treatment of chronic granulomatous disease

Abstract

Purpose of review: Chronic granulomatous disease (CGD), characterized 50 years ago as a primary immunodeficiency disorder of phagocytic cells (resulting in failure to kill a defined spectrum of bacteria and fungi and in concomitant chronic granulomatous inflammation) now comprises five genetic defects impairing one of the five subunits of phagocyte NADPH oxidase (Phox). Phox normally generates reactive oxygen species (ROS) engaged in intracellular and extracellular host defence and resolving accompanying inflammatory processes. 'Fatal' granulomatous disease has now changed into a chronic inflammatory condition with a median survival of 35 years and is now of interest to both paediatricians and internists. Clinical vigilance and expert knowledge are needed for early recognition and tailored treatment of this relatively rare genetic disorder.

Recent findings: Infections by unanticipated pathogens and noncirrhotic portal hypertension need to be recognized as new CGD manifestations. Adult-onset CGD too is increasingly observed even in the elderly. Conservative treatment of fungal infections needs close monitoring due to the spread of azole resistance following extensive use of azoles in agriculture. Curative haematopoietic stem cell transplantation (HSCT) in early childhood has expanded with impressive results following use of matched, unrelated or cord blood donors and of a reduced intensity conditioning (RIC) regimen. Gene therapy, however, still has major limitations, remaining experimental.

Summary: CGD is more prevalent than initially believed with a birth prevalence of 1: 120 000. As patients are increasingly diagnosed around the world and grow older, further manifestations of CGD are expected. While fungal infections have lost some threat, therapeutic research focuses on two other important aims: pharmacologic cure of chronic inflammation and long-term cure of CGD by gene therapy.