Association between HLA system and susceptibility to Typhoid fever

Abstract

Infectious Disease are associated with impaired immunity. The level of response is determined by several factors: intensity of infections, intensity of host immune response, and genetic factor. Human Leukocyte Antigens (HLA) system plays an important role in cell-to-cell interaction in the immune system. Association between HLA and some infectious diseases has been established. Because Indonesia has the highest prevalence of typhoid fever, a research on the possible association between HLA antigen and susceptibility to typhoid fever was carried out. HLA antigen were determined by microlymphocytotoxicity test using Terasaki’s dry tray. Thirty blood samples were collected from typhoid fever patients with positive blood culture taken from Dr. Soetomo Hospital Surabaya. As a control 30 blood samples were taken from subjects who had never had a prolonged fever more than 5 days, and negative urine and faeces culture for Salmonella spp. Statictical analysis were done by Chi-square test for n > 5 and Fisher’s Exact test for n < 5. Results indicated that there was an association between HLA antigen and susceptibility to typhoid fever. This proved the existance of genetic predisposition in which individuals with HLA antigen B7 and DR10 are prone to gel typhoid fever, whereas individuals with HLA antigen B18 has a protective factor to prevent typhoid fever.