Interleukin-1 receptor antagonist gene polymorphism in patients with multidrug-resistant Acinetobacter baumannii-associated pneumonia

OBJECTIVE: Multidrug-resistant Acinetobacter baumannii (MDRAB)-associated pneumonia has been a common disease and a therapeutic problem in hospitals. Interleukin-1 receptor antagonist (IL-1ra) has been considered a required role for host immune defense in pneumonia disease. The aim of this study was to investigate whether the variable nucleotide tandem repeat polymorphism of the IL-1ra gene was associated with MDRAB-related pneumonia. METHODS: Sixty-six pneumonia patients were enrolled in the study: 36 subjects had MDRAB-related pneumonia and 30 controls had non-MDRAB pneumonia. Polymerase chain reaction, restriction fragment length polymorphism, and agarose gel electrophoresis techniques were used to determine the IL-1ra genotype. RESULTS: The frequencies of the IL-1ra genotype in the MDRAB-related pneumonia cases were A1/A1, 0.889 and A1/A2, 0.111; the frequencies of the IL-1ra genotype in the controls were A1/A1, 0.333 and A1/A2, 0.667. A statistically significant difference was determined (P < 0.05). We also observed an increase in the frequency of IL-1ra A1 allele in the MDRAB-related pneumonia group. A statistically significant difference was determined (P<0.05). CONCLUSIONS: We suggested that IL-1ra polymorphism was associated with the risk of MDRAB-related pneumonia.