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Following in Real Time the Impact of Pneumococcal Virulence Factors in an Acute Mouse Pneumonia Model Using Bioluminescent Bacteria
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Following in Real Time the Impact of Pneumococcal Virulence Factors in an Acute Mouse Pneumonia Model Using Bioluminescent Bacteria

Published on: February 23, 2014

Genetic variants of the MBL2 gene are associated with mortality in pneumococcal sepsis

José Garnacho-Montero1, Emilio García-Cabrera, Rocio Jiménez-Álvarez

  • 1Critical Care and Emergency Department, Hospital Universitario Virgen del Rocío, Seville, Spain. jgarnachom@telefonica.net

Diagnostic Microbiology and Infectious Disease
|May 15, 2012
PubMed

Insights

Genetic variants in the mannose-binding lectin 2 (MBL2) gene are linked to increased mortality in pneumococcal sepsis patients. Early antibiotic administration showed a protective effect against death in these patients.

Area of Science:

  • Immunogenetics
  • Infectious Diseases
  • Critical Care Medicine

Background:

  • Conflicting results exist regarding the association between innate immunity gene polymorphisms and infectious disease prognosis.
  • Pneumococcal sepsis is a significant cause of mortality, and understanding its genetic underpinnings is crucial for improving patient outcomes.

Purpose of the Study:

  • To investigate the impact of specific genotypic variants in innate immunity genes on mortality in patients with pneumococcal sepsis.
  • To identify genetic factors and clinical variables independently associated with in-hospital and 90-day mortality.

Main Methods:

  • A cohort of 117 adult patients with Streptococcus pneumoniae sepsis was analyzed.
  • Genotyping was performed for single-nucleotide polymorphisms (SNPs) in MBL2, TLR2, TLR4, and FcγRIIa genes.
  • Clinical data including underlying diseases, illness severity, and antibiotic timing were recorded and analyzed for association with mortality.

Main Results:

  • Allelic variants in the MBL2 gene (AO/OO genotypes) were found in 32% of patients.
  • MBL2 gene variants (SNP MBL2 AO/OO) were independently associated with increased in-hospital mortality (aHR 3.2) and 90-day mortality (aHR 2.2).
  • Septic shock was a strong predictor of mortality (aHR 15.3), while timely antibiotic administration (≤ 4 hours) was protective (aHR 0.2).

Conclusions:

  • Variant alleles in the MBL2 gene are independently associated with both in-hospital and medium-term mortality in pneumococcal sepsis.
  • Genetic predisposition, particularly MBL2 variants, plays a role in pneumococcal sepsis outcomes.
  • Optimizing antibiotic treatment timing remains a critical factor in reducing mortality.

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