An international study published in the journal Blood by researchers led by Dr. Elie Haddad, a pediatric immunologist and researcher at CHU Sainte-Justine and professor at Université de Montréal, highlights the urgent need to develop better treatment strategies for patients suffering from severe combined immune deficiency (SCID).
This deficiency, better known as “bubble baby disease” is a rare syndrome characterized by a total non-function of the body’s immune system. The children affected have no immune defence and are vulnerable to bacteria, viruses and fungi, resulting in repeated severe infections. Without appropriate treatment, in most cases this disease is fatal within the first months after birth.
SCID can be caused by mutations in various genes involved in the functioning of the immune system. The new research shows that the nature of the mutated gene (or genotype) has a significant influence on patients’ survival and reconstitution of their immune system after bone marrow transplant. According to the study, the genotype must be taken into account when adapting treatment strategies to individual patients.
The results showed that survival rates of patients were higher after a cell transplant from a matched sibling donor. In recipients from other donor types, which represent 86 per cent of cases, the data showed that the SCID genotype had a strong influence on survival and immune reconstitution. In addition, the researchers found that young age and absence of active infection at the time of transplant were also key factors for survival, and both were significantly associated with improved survival following a transplant.