Pilot study proposal on non-selective response to vaccination against HBV in children with juvenile idiopathic arthritis

The etiology of Juvenile Idiopathic Arthritis (JIA) is unknown though some correlations has been found with HLA genes. Since it is known that the immune response to HBV vaccine is largely determined by the presentation of the immunogenic peptides through HLA-DR and DQ molecules, it has been suggested that the presence of some of these haplotypes predisposes to a lower response to this vaccine. Some studies have found that patients affected by coeliac disease and type 1 diabetes mellitus have a less effective response to hepatitis B vaccination. The cause can probably be attributed to patients’ genetic predisposition or the inflammatory condition established if the coeliac patient doesn’t follow the correct gluten-free diet. In literature we found no studies on HBV vaccination response in patients affected by JIA. We hypothesized to lead a pilot study dosing the antibody titer against mandatory vaccines and lymphocyte activity after stimulation with HBV antigens in all our JIA patients, as well as performing immunological first level exams and HLA genes. Furthermore these same parameters will be studied in two groups of children similar in age and sex: a group of coeliac patients and an healthy control group. We casually found some of our patients affected by JIA without the necessary antibody against HBV, although it has been shown that this may not be correlated with the real ability of the immune system to react to HBV infection. This study may be useful to identify patients susceptible to HBV infection and to improve vaccinal policies.