Repeated cytogenetic culture failure as an indicator of immunodeficiency

Immunological aspects of 22q11.2 deletion syndrome

Chromosome 22q11 deletion is the most common chromosomal deletion syndrome and is found in the majority of patients with DiGeorge syndrome and velo-cardio-facial syndrome. Patients with CHARGE syndrome may share similar features. Cardiac malformations, speech delay, and immunodeficiency are the most common manifestations. The immunological phenotype may vary widely between patients. Severe T lymphocyte immunodeficiency is rare-thymic transplantation offers a new approach to treatment, as well as insights into thymic physiology and central tolerance. Combined partial immunodeficiency is more common, leading to recurrent sinopulmonary infection in early childhood. Autoimmunity is an increasingly recognized complication. New insights into pathophysiology are reviewed.

Diagnosis of severe combined immunodeficiency

Early diagnosis of severe combined immunodeficiency (SCID) is important to enable prompt referral to a supraregional centre for bone marrow transplantation before the occurrence of end organ damage secondary to infective complications. This review outlines clinical, microbiological, and immunopathological clues that aid the diagnosis of SCID and emphasises the multidisciplinary approach needed to diagnose and treat these infants.