Versione in italiano
WHAT IS IT
Chronic granulomatous disease is an immunodeficiency caused by a defect in neutrophils. Neutrophils are blood cells that mediate the defence mainly against bacterial and fungal infections.
HOW IS IT INHERITED
The X-linked form is the most frequent and is caused by the presence of a defective gene called CYBB located on the X chromosome. This defective gene does not allow the correct synthesis of a protein (gp91) which is important for appropriate functioning of neutrophils. The disease mainly affects males. The CYBB gene is located on the X chromosome and therefore the presence of only one copy of the defective gene is enough to determine disease in males (who having X and Y sex chromosomes have only one copy of the X chromosome). On the other hand, the presentation of the disease is rarer in females in whom two defective copies of the gene are required (females have 2 X chromosomes).
HOW DO WE RECOGNIZE IT
The disease is characterized by the patient’s inability to fight mainly bacterial and fungal infections. This results in a state of hyperinflammation which leads to the development of granulomas which can generate complications in the genitourinary, gastrointestinal and pulmonary systems. The disease, in the X-linked form which is the most severe, is suspected in the first months / years of life due to the onset of serious infections, especially bacterial and fungal. The disease can be related either to a new mutation arisen in a family (de novo) or to an inherited mutation already present in the maternal lineage. The suspicion in this case may occur if there are relatives, in the mother's family and mainly males, who have had frequent and serious infections since childhood.
HOW DO WE TREAT IT
When the diagnosis is suspected, it is necessary to contact a referral center for the pathology. Being a rare disease, it is mandatory to confirm the diagnosis performing functional (DHR, NBT test) and genetic analysis that can only be performed in a few centers in Italy. After the diagnosis is made it is important that antibacterial and antifungal prophylaxis are initiated which will allow you to respond more quickly in the event of an infection. However, recent international experience has shown that, at present, the only definitive cure is represented by hematopoietic stem cell transplantation. Transplantation results from highly compatible donors are superimposable to those of other hematological diseases and its favorable outcome increases if it is performed before the onset of chronic inflammatory complications and/or organ damage. Gene therapy is currently considered experimental. In Europe, a multicenter study has been closed but to date only preliminary results are available.
REFERRING DOCTORS for this desease
at Ospedale San Raffaele