Performance of immunological assays for universal and differential diagnosis of HTLV-1/2 infection in candidates for blood donations from the Brazilian Amazon.

The present study compares the ability of distinct immunological assays (chemiluminescence immunoassay-CLIA, western blot-WB and flow cytometry-FC-Simplex and Duplex) to detect anti-HTLV (human T-lymphotropic virus) antibodies in candidates for blood donations at the Amazonas State Blood Center (Brazil) between January 2018 and December 2022. Overall, 257,942 samples from candidates for blood donations were screened using CLIA, which led to 0.15% seropositivity for HTLV (409 samples). A total of 151 candidates for blood donations were enrolled for retesting with CLIA followed by additional testing using WB and FC-Simplex and Duplex analysis. Our results demonstrated that 62% (93/151), 20% (30/151) and 17% (26/151) of the samples presented positive results with retesting using CLIA, WB and FC-Simplex analysis, respectively. Additional analysis of the CLIA, WB and FC-Simplex results revealed an overall agreement of 56% for CLIA and WB (22 co-negative; 30 co-positive samples), 48% for CLIA and FC-Simplex (21 co-negative; 24 co-positive samples) and 80% for WB and FC-Simplex (51 co-negative; 23 co-positive samples). Considering the WB as the reference standard for the diagnosis of infection with HTLV-1/2, we observed that the CLIA results of ≤3.0 RLU and >10.0 RLU in the retest can be used define a negative or positive result, respectively, and could be used as new specific cut-off values. The overall agreement between WB and FC-Duplex for accomplishing the differential diagnosis was evaluated and demonstrated 100% correspondence for the diagnosis of HTLV-1 (15/15) and HTLV-2 (7/7). Our findings demonstrate that gaps in the diagnosis of infection with HTLV-1/2 could be overcome by the simultaneous use of distinct immunological assays during retesting of candidates for blood donations.

Association of Toll-like receptors polymorphisms with the risk of acute lymphoblastic leukemia in the Brazilian Amazon.

Acute lymphoblastic leukemia (ALL) is the most common hematologic malignancy in children in childhood. Single-nucleotide polymorphism (SNPs) in key molecules of the immune system, such as Toll-like receptors (TLRs) and CD14 molecules, are associated with the development of several diseases. However, their role in ALL is unknown. A case-control study was performed with 152 ALL patients and 187 healthy individuals to investigate the role of SNPs in TLRs and the CD14 gene in ALL. In this study, TLR6 C > T rs5743810 [OR: 3.20, 95% CI: 1.11-9.17, p = 0.003) and TLR9 C > T rs187084 (OR: 2.29, 95% CI: 1.23-4.26, p = 0.000) seems to be a risk for development of ALL. In addition, the TLR1 T > G rs5743618 and TLR6 C > T rs5743810 polymorphisms with protection against death (OR: 0.17, 95% IC: 0.04-0.79, p = 0.008; OR: 0.48, 95% IC: 0.24-0.94, p = 0.031, respectively). Our results show that SNPs in TLRs genes may be involved in the pathogenesis of ALL and may influence clinical prognosis; however, further studies are necessary to elucidate the role of TLR1, TLR4, TLR5, TLR6, TLR9 and CD14 polymorphisms in this disease.

Genetic polymorphisms of inflammasome genes associated with pediatric acute lymphoblastic leukemia and clinical prognosis in the Brazilian Amazon.

The immune system plays an important role in the control of cancer development. To investigate the possible association of inflammasome genes to childhood leukemia we performed a case-control study with 158 patients with acute lymphoblastic leukemia and 192 healthy individuals. The IL1B and IL18 genetic polymorphisms were genotyped by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) and NLRP1, NLRP3 and P2RX7 were genotyped using Real Time quantitative PCR (qPCR). The IL1B C/T rs19644 genotype was associated with the risk of developing ALL (C/C vs. C/T + T/T OR: 2.48 [95% CI: 1.26-4.88, p = 0.006]; C/C vs C/T OR: 2.74 [95% CI: 1.37-5.51, p = 0.003]) and the NLRP1 A/T rs12150220 (OR: 0.37 [95% CI: 0.16-0.87, p = 0.023]) was associated with protection against infectious comorbidities. It was not found association between NLRP3 and P2RX7 polymorphisms and acute lymphoblastic leukemia in our study. Our results suggest that the inflammasome single-variant polymorphisms (SNVs) may play a role in the development and prognostic of childhood leukemia. However, this finds requires further study within a larger population in order to prove it.

Out-of-hospital deliveries: A case-control study.

AIM: To identify the factors, risks, and mortality associated with unplanned out-of-hospital births. MATERIAL AND METHODS: This observational, retrospective, case-control study was conducted between 2005 and 2013 through a review of medical records from the hospital network of a county of Brazil. Mother-child dyads were divided into in-hospital births and unplanned out-of-hospital births. For hypothesis testing involving quantitative variables, parametric and nonparametric methods (t-test or Mann-Whitney test, respectively) were used as appropriate after ascertaining normality of distribution via the Kolmogorov-Smirnov or Shapiro-Wilk tests. The chi-square test, Fisher's exact test, odds ratios, and 95% confidence intervals were used to assess the relationship between categorical variables. A binary logistic regression was applied for pooled analysis of those variables that, when analyzed in isolation, had significant p-values on hypothesis testing. In all tests, p-values <0.05 were considered statistically significant. RESULTS: Of the 420 records, 117 corresponded to out-of-hospital births dyads. Mothers were predominantly nonwhite (p<0.001), with a history of inadequate antenatal care (p<0.001), multiparous (p<0.001), aged >25 years (p=0.031), and had more puerperal complications (p<0.001). Their newborns had low birth weight (Odds Ratios: 2.22; 95% CI: [1.4-3.4]; p<0.001), higher morbidity (p=0.009), a higher rate of admission to neonatal intensive care and stepdown units (p=0.030), and prolonged length of stay (p<0.001). CONCLUSION: The risk of maternal and neonatal complications, as well as the neonatal mortality rate, were higher for unplanned out-of-hospital deliveries. It occurred predominantly in nonwhite, older, multiparous women who had received incomplete antenatal care and who lived far from perinatal care centers.