Tuberculosis diagnosis: algorithm that May discriminate latent from active tuberculosis.

Diagnosis of tuberculosis still faces a lot of challenges and is one of the priorities in the field of tuberculosis management. Deciphering the complex tuberculosis pathogenicity network could provide biomarkers for diagnosis. We discussed the distribution of HLA-B17, -DQB and -DRB together with QuantiFERON test results in tuberculosis infection. A case control study was done during which a total of 337 subjects were enrolled comprising 227 active tuberculosis (ATB), 46 latent tuberculosis infection (LTBI) and 64 healthy controls (HC). Sequence-specific primer polymerase chain reaction and immune epitope database were used to genotype samples and determine the epitope binding ability of the over-represented alleles respectively. QuantiFERON test was done according to manufacturer's instructions. The peptides HLA-B*5801 and HLA-DRB1*12 and the peptides HLA-B*5802 and HLA-DQB1*03 were found to be associated with latent tuberculosis while the haplotypes DRB1*10-DQB1*02 and DRB1*13-DQB1*06 were found to be associated with active tuberculosis (All p-values≤0.05). The association of HLA-B*5801 and HLA-B*5802 with latent tuberculosis was linked to their ability to bind or not mycobacterial antigens. DRB1*10-DQB1*02 haplotype was found to be over-represented in LTBI compared to ATB (p-value = 0.0015) while DRB1*13-DQB1*06 was found to be under-represented in LTBI compared to ATB (p-value = 0.0335). The DRB1*10-DQB1*02 haplotype was only found in the LTBI when compared with the ATB group. The present study suggests the following algorithm to discriminate LTBI from ATB: QuantiFERON+ and DRB1*10-DQB1*02 haplotype + may indicate LTBI; QuantiFERON+ and DRB1*10-DQB1*02 haplotype - may indicate ATB.

Maternal age, infant age, feeding options, single/multiple pregnancy, type of twin sets and mother-to-child transmission of HIV.

BACKGROUND: Some risk factors for mother-to-child transmission (MTCT) of HIV have been identified. To further reduce MTCT, other risk factors were evaluated. MATERIALS AND METHODS: A retrospective study on early infant diagnosis was conducted. Two-sided chi-square test was used to assess associations with infant HIV status. RESULTS: A total of 15 233 HIV-infected mothers and 15 404 infants were recruited. MTCT rate was 9.34%. Only 3.8% of infants born to mothers on antiretroviral treatment were infected. Under nevirapine, 4.1% of infants were infected. MTCT increased with infant' age at testing. Younger mothers tend to transmit more HIV (P = 0.003). More children were infected in single pregnancies compared with multiple pregnancies, P < 0.001. There were more infections in male-female twins' sets (P = 0.037). CONCLUSIONS: Maternal age, type of pregnancy and twins' sets are new MTCT risk factors. Strategies to further decrease transmission through family planning, pre/post natal consultations and clinical practices are needed.

Distribution of CCR5-Delta32, CCR5 promoter 59029 A/G, CCR2-64I and SDF1-3'A genetic polymorphisms in HIV-1 infected and uninfected patients in the west region of Cameroon.

BACKGROUND: Genetic variants of the genes encoding human immunodeficiency virus-1 (HIV-1) co-receptors and their ligands, like CC-chemokine receptor 5 delta 32 mutation (CCR5-Delta32), CCR5 promoter A/G (Adenine/Guanine), CC-chemokine receptor 2 mutation 64 isoleucine (CCR2-64I) and the stromal cell-derived factor 3'A mutation (SDF1-3'A), are involved in the susceptibility to HIV-1 infection and progression. The prevalence of these mutations varies by region. However, little is known about their distribution in the population of Dschang, located in the west region of Cameroon. The prevalence of HIV in the west region of Cameroon is lower than elsewhere in Cameroon. The objectives of this study were to determine the distribution of four AIDS Related Gene (ARG) variants in HIV-infected and non-infected population of Cameroon especially in the west region and to estimate the contribution of these variants to the susceptibility or resistance to HIV infection. We also aimed to evaluate the effectiveness of genotyping using dried blood spot (DBS) samples. METHODS: A total of 179 participants were recruited from two hospitals in Dschang in the west region of Cameroon. Their genotypes for CCR5-Delta32, CCR5 promoter 59029A/G, CCR2-64I and SDF1-3'A were analyzed using polymerase chain reaction (PCR) and restriction fragment length polymorphisms. RESULTS: A total of 179 participants were enrolled in the study. Among them, 32 (17.9%) were HIV positive and 147 (82.1%) were HIV negative. The allelic frequencies of these genes were: 0%, 49.72%, 17.6% and 100% respectively for CCR5-Delta32, CCR5 promoter 59029A/G, CCR2-64I and SDF1-3'A. No individual was found to carry the CCR5-Delta 32 mutation. All participants recruited were heterozygous for the SDF1-3'A allele. CONCLUSION: Our data suggest that the CCR5-Delta32 cannot account for the protection as it was completely absent in our population. SDF1-3'A variants, may be in association with other polymorphisms, may account for the overall protection from HIV-1 infection in participants recruited as everyone carries this allele. The CCR5 promoter 59029 G/G genotype may be associated with the risk for HIV-1 infection in this population, while the CCR2-64I (A/A genotype) may account for the protection against HIV infection. The results of genotyping from fresh blood and DBS were comparable.