Severe Combined Immunodeficiency is a primary immune deficiency. It is actually a group of inherited disorders that cause severe abnormalities of the immune system. SCID is often called “bubble boy disease”.
SCID became widely known during the 1970’s and 80’s, when the world came to know about David Vetter, a boy who lived for 12 years in a plastic, germ-free bubble with X-linked SCID. The disorders lead to reduced or malfunctioning T- and B-lymphocytes.
SCID usually results in the onset of one or more serious infections within the first few months of life. These infections are usually serious, and may even be life threatening. They may include pneumonia, meningitis or bloodstream infections.
The combined immune deficiency is a serious problem in infants and the infant may die with in the first two years by recurrent infections.
Several CSID case studies reveal that a gene on the X-chromosome is responsible for this disease in 50% of patients. And the remaining 50% are due to several autosomal recessive inheritance patterns or the result of spontaneous mutations in genes such as defective adenosine deaminase, and purine nucleoside phosphorylase (PNP) genes on other chromosomes.
Deficiency of these enzymes results in the accumulation of metabolites that in turn inhibits the replication of lymphocytes. Bone marrow transplantation or gene therapy can help in saving the patient.