Infectious complications are a leading cause of morbidity and mortality in patients with sickle cell disease. Several mechanisms are supposed to contribute to this susceptibility. The exact reasons for the susceptibility of sickle cell patients to infection are not clear and are still a matter of debate. Interferon gamma (IFNgamma) is a key cytokine involved mainly in the defence against intracellular pathogens. We investigated a possible association of an IFNgamma +874 T/A polymorphism and infectious complications in sickle cell patients. Seventy-two sickle cell patients were typed for +874 T/A IFNgamma polymorphism. Genotype frequencies were different between cases and controls. Indeed, the T allele frequency was significantly higher in patients with infections than in patients without infections (P = 0.014). Our results suggest that the +874 T/A IFNgamma polymorphism is associated with infectious complications in sickle cell patients. T allele could be involved in infections in sickle cell patients.