HLA Polymorphism in Algerian Children With Lymphomas.

BACKGROUND: Non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL) are the 2 types of lymphoma that represent the third most common childhood malignancy. Multiple etiological factors are involved in lymphoma pathogenesis, including viral infection, immune deficiencies, environmental agents, and genetic factors. Strong arguments supporting a genetic linkage between the susceptibility to lymphomas and human leukocyte antigens (HLA) are reported and give an idea about susceptibility or protection from the disease. METHODS: Seventy-one cases were included in this study: 36 cases of non-Hodgkin lymphoma and 35 patients with Hodgkin lymphoma. Their ages ranged from 4 to 18 years. The control group consisted of 70 unrelated healthy individuals, with a mean age of 5 to 17 years. The genotype of HLA-A, HLA-B, HLA-DR, and HLA-DQ alleles was typed by means of PCR sequence-specific priming. RESULTS: HLA-B*18, HLA-DRB1*03, *07, and HLA-DQB1*02 were significantly increased in patients with lymphomas when compared with controls, whereas HLA-DRB1*13 and DQB1*03 were significantly decreased when compared with controls. CONCLUSIONS: These results indicate that HLA-B*18, DRB1*03, *07, and DQB1*02 may contribute to lymphoma susceptibility, whereas HLA-DRB1*13 and DQB1*03 may confer protection to lymphoma in the Algerian population.

Diagnostic and Predictive Contribution of Autoantibodies Screening in a Large Series of Patients With Primary Immunodeficiencies.

Objectives: To evaluate the diagnostic and predictive contribution of autoantibodies screening in patients with primary immunodeficiencies (PIDs). Methods: In the present study, PID patients and healthy controls have been screened for 54 different autoantibodies. The results of autoantibodies screening in PID patients were correlated to the presence of autoimmune diseases. Results: A total of 299 PID patients were included in this study with a predominance of antibody deficiencies (27.8%) followed by immunodeficiencies affecting cellular and humoral immunity (26.1%) and complement deficiencies (22.7%). Autoimmune manifestations were present in 82 (27.4%) patients. Autoimmune cytopenia (10.4%) was the most common autoimmune disease followed by gastrointestinal disorders (10.0%), rheumatologic diseases (3.7%), and endocrine disorders (3.3%). Autoantibodies were found in 32.4% of PID patients and 15.8% of healthy controls (P < 0.0005). Anti-nuclear antibodies (ANA) (10.0%), transglutaminase antibody (TGA) (8.4%), RBC antibodies (6.7%), anti-smooth muscle antibody (ASMA) (5.4%), and ASCA (5.0%) were the most common autoantibodies in our series. Sixty-seven out of the 82 patients with autoimmune manifestations (81.7%) were positive for one or more autoantibodies. Eleven out of the 14 patients (78.6%) with immune thrombocytopenia had positive platelet-bound IgM. The frequencies of ASCA and ANCA among patients with IBD were 47.4% and 21.0% respectively. All patients with celiac disease had TGA-IgA, while six out of the 11 patients with rheumatologic diseases had ANA (54.5%). Almost one third of patients (30/97) with positive autoantibodies had no autoimmune manifestations. ANA, rheumatoid factor, ASMA, anti-phospholipid antibodies and ANCA were often detected while specific AID was absent. Despite the low positive predictive value of TGA-IgA and ASCA for celiac disease and inflammatory bowel disease respectively, screening for these antibodies identified undiagnosed disease in four patients with positive TGA-IgA and two others with positive ASCA. Conclusion: The present study provides valuable information about the frequency and the diagnostic/predictive value of a large panel of autoantibodies in PIDs. Given the frequent association of some AIDs with certain PIDs, screening for corresponding autoantibodies would be recommended. However, positivity for autoantibodies should be interpreted with caution in patients with PIDs due to their low positive predictive value.