Background: Malaria is among the most prevalent parasitic diseases worldwide. In Brazil, malaria is concentrated in the northern region, where Plasmodium vivax accounts for 85% disease incidence. The role of genetic factors in host immune system conferring resistance/susceptibility against P. vivax infections is still poorly understood. Methods: The present study investigates the influence of polymorphisms in 18 genes related to the immune system in patients with malaria caused by P. vivax. A total of 263 healthy individuals (control group) and 216 individuals infected by P. vivax (malaria group) were genotyped for 33 single nucleotide polymorphisms (SNPs) in IL1B, IL2, IL4, IL4R, IL6, IL8, IL10, IL12A, IL12B, IL12RB1, SP110, TNF, TNFRSF1A, IFNG, IFNGR1, VDR, PTPN22 and P2X7 genes. All subjects were genotyped with 48 ancestry informative insertion-deletion polymorphisms to determine the proportion of African, European and Amerindian ancestry. Only 13 SNPs in 10 genes with differences lower than 20% between cases and controls in a Poisson Regression model with age as covariate were further investigated with a structured population association test. Results: The IL1B gene -5839C > T and IL4R 1902A > G polymorphisms and IL12RB1 -1094A/-641C and TNF -1031 T/-863A/-857 T/-308 G/-238 G haplotypes were associated with malaria susceptibility after population structure correction (p = 0.04, p = 0.02, p = 0.01 and p = 0.01, respectively). Conclusion: Plasmodium vivax malaria pathophysiology is still poorly understood. The present findings reinforce and increase our understanding about the role of the immune system in malaria susceptibility.

Background Veno-occlusive disease with immunodeficiency (VODI) is an autosomal recessive disorder of combined immunodeficiency (CID) and hepatic injury. Hematopoietic stem cell transplantation (HSCT) the only definitive treatment for CID appeared to have a high rate of complications in a previous report. In this study, we describe a new group of patients with VODI highlighting further clinical and immunologic aspects of this disease and re-evaluating the effectiveness of HSCT for the treatment of this disorder. Patients and methods Review of clinical data, immunologic features, molecular studies, treatment, and final outcome of eight kindred members with VODI. Results The patients described had clinical and immunologic findings consistent with VODI. The molecular studies revealed a new mutation in the SP110 gene. HSCT was carried out in five patients and was successful in three. Conclusions The diagnosis of VODI should be considered in all patients regardless of ethnicity with a severe combined immunodeficiency (SCID)-like presentation, especially with a normal mitogen response, or with signs of hepatic injury. VODI is a primary immune deficiency, which can be successfully corrected by bone marrow transplantation if applied early in the course of disease using appropriate conditioning.