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Toll-like receptor genetic variants are associated with Gram-negative infections in VLBW infants.

ABSTRACT: To test the hypothesis that single-nucleotide polymorphisms (SNPs) in Toll-like receptor (TLR) genes alter susceptibility to bacterial infections and modulate white blood cell (WBC) counts during infections in very low birth weight (VLBW) infants (birth weight <1500 g).VLBW infants recruited in a multicenter study were genotyped for nine functional TLR SNPs and associations between SNPs and infection rates examined. WBC counts obtained during infections were compared among infants with and without SNPs.In our cohort (n=408), 90 infants developed bacterial infections. Presence of TLR4 (rs4986790 and rs4986791) variants were associated with Gram-negative (G-ve) infections. Female infants heterozygous for the X-linked IRAK1 (rs1059703) SNP had less G-ve infections. In regression models controlling for confounders, the TLR4 (rs4986790) SNP was associated with increased G-ve infections. The TLR5 (rs5744105) variant was associated with elevated WBC counts during infections.TLR genetic variants can contribute to increased risk of bacterial infections and altered immune responses in VLBW infants.

SUBMITTER: Sampath V

PROVIDER: S-EPMC4465440 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Toll-like receptor genetic variants are associated with Gram-negative infections in VLBW infants.

Sampath V V Mulrooney N P NP Garland J S JS He J J Patel A L AL Cohen J D JD Simpson P M PM Hines R N RN

Journal of perinatology : official journal of the California Perinatal Association 20130718 10

<h4>Objective</h4>To test the hypothesis that single-nucleotide polymorphisms (SNPs) in Toll-like receptor (TLR) genes alter susceptibility to bacterial infections and modulate white blood cell (WBC) counts during infections in very low birth weight (VLBW) infants (birth weight <1500 g).<h4>Study design</h4>VLBW infants recruited in a multicenter study were genotyped for nine functional TLR SNPs and associations between SNPs and infection rates examined. WBC counts obtained during infections wer ...[more]

PMID: 23867959

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Project description:BACKGROUND:Rates of colonization and infection with carbapenem-resistant Gram-negative pathogens are on the rise, particularly in southeastern European countries, and this is increasingly true in Germany as well. The organisms in question include enterobacteriaceae such as Klebsiella pneumoniae and Escherichia coli and non-fermenting bacteria such as Pseudomonas aeruginosa and Acinetobacter baumannii. As the carbapenems have been the gold standard to date for the systemic treatment of serious infections with Gram-negative bacteria, carbapenem resistance presents new and difficult challenges in therapeutic decision-making, particularly because of the high frequency of coresistance. METHODS:This review is based on pertinent publications retrieved by a selective search in PubMed and on other applicable literature. RESULTS:Multiresistant Gram-negative (MRGN) pathogens are classified in Germany according to their resistance to four different classes of antibiotics; fluoroquinolones, piperacillin, third-generation cephalosporins, and carbapenems. Quadruple MRGN pathogens are resistant to all four groups, triple MRGN pathogens to three of them. There are a number of therapeutic alternatives to carbapenems that can be applied with the aid of sensitive microbiological and/or molecular genetic testing. The following antibiotics are often the only ones that can be used to treat quadruple MRGN pathogens: colistin, aminoglycosides, tigecycline, fosfomycin, ceftazidime/avibactam, and ceftolozan/tazobactam. Carbapenems, too, may still be an option in certain situations. There is also evidence that combinations of antibiotics against which the pathogen is resistant individually can some- times be a valid treatment option; these include combinations of colistin with one or two carbapenems. CONCLUSION:The treatment of severe infection with carbapenem-resistant pathogens should be individualized and carried out in an interdisciplinary framework, in consideration of antibiotic pharmacokinetics and pharmacodynamics in each case. The treat- ment options are based on evidence from in vitro studies, retrospective studies, and case series, which must be interpreted with caution. Randomized clinical trials are needed to test each of the various combined approaches.

Dataset Information

Toll-like receptor genetic variants are associated with Gram-negative infections in VLBW infants.

Publications

Toll-like receptor genetic variants are associated with Gram-negative infections in VLBW infants.

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