THE CLINICAL FEATURES AND
HLA SUSCEPTIBILITY LOCUS FOR PATIENTS WITH IGA DEFICIENCY
Kilic SS, Sun HI, Aydogdu H
Uludag University Medical
Faculty,
Department of Pediatrics,
Immunology Division, Bursa, Turkey
Objective: Ig A deficiency is the most common form of primary
immunodeficiency and affects approximately 1/600 individuals. The term 搒elective IgA deficiency (SIg
AD) should be reserved for those individuals who do not have identifable
disorders which are known to be associated with low Ig A levels. Ig G
subclass deficiency or a lack of specific anti-polysaccharide antibodies of
the Ig G2 subclass is seen in many cases.
Methods: We performed our clinical trial by including 45 patients with
Ig A deficiency applied to Pediatric Immunology department, Medical Faculty
of Uludag University. Serum immunoglobulin (Ig) class and Ig G subclass concentrations
and HLA haplotypes were determined prospectively in patients and control
groups.
Results: The mean age of the patients was 5 years 5 months and 18
patients (40%) of the group were female while 27 patients (60 %) were male.
Patients with SIgAD had low level of IgM, and 2 patient of this group had
low level of IgG. The rest of the patients’ Ig levels were in the normal
rates. In 22 patients, we also checked the family serum Ig levels. In
family members of the patients, five had low levels of IgM and 1 had low
levels of IgA and Ig G. In 23 patients we checked the subgroups of IgG
levels. One patient had low levels of IgG1 and 2 had low levels of IgG2 and
IgG3, 10 had low levels of IgG3. Ig G subclass concentrations were found
normal in control groups.
We determined the MHC susceptibility genes in 25 patients. The
extended major histocompatibility complex (MHC) haplotype HLA A1, B8, B14,
DR1, DR3, DR7 is increased in frequency among patients with Ig A
deficiency. HLA A1 locus found in 3 patients (12 %), HLA B14 in 3 patients
(12%), HLA DR1 in 10 patients (40 %), HLA DR7 in 4 patients (16 %) and HLA
DR3 in 1 patient (4 %). There was no patient with HLA B8 positive locus.
Fifteen children has chosen as the control group who had normal Ig A levels
but they had HLA DR1 (26 %), HLA DR7 (13 %), HLA B8 (6%), HLA DR3 (20%) and
HLA A1 was not found in any members of our control groups.
Conclusions: We could not find any statistically difference for HLA
susceptibility genes between patients and control groups.