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Published on: April 5, 2019

Low serum mannose-binding lectin level increases the risk of death due to pneumococcal infection

Damon P Eisen1, Melinda M Dean, Marja A Boermeester

  • 1Centre for Clinical Research Excellence in Infectious Diseases, Victorian Infectious Diseases Service, Royal Melbourne Hospital, Parkville, Victoria, Australia. damon.eisen@mh.org.au

Clinical Infectious Diseases : an Official Publication of the Infectious Diseases Society of America
|July 10, 2008
PubMed
Abstract

Insights

Low mannose-binding lectin (MBL) levels are linked to increased sepsis mortality, especially in severe pneumococcal infections. A defined MBL deficiency cutoff of 0.5 microg/mL aids future research into this innate immune protein.

Area of Science:

  • Immunology
  • Infectious Diseases
  • Genetics

Background:

  • Previous studies suggest a link between low mannose-binding lectin (MBL) levels or MBL2 genotypes and sepsis susceptibility.
  • However, MBL deficiency lacks a rigorous definition, and its impact on sepsis outcomes requires further investigation through multivariable analysis.

Purpose of the Study:

  • To rigorously define MBL deficiency using a reliable cutoff value.
  • To investigate the association between MBL deficiency and sepsis outcomes, including mortality, using multivariable analysis.

Main Methods:

  • Reanalyzed MBL data from 1642 healthy controls across 4 studies to establish a deficiency cutoff.
  • Utilized receiver operating characteristic analysis to determine a reliable MBL cutoff value.
  • Reassessed individual data from 675 patients across 6 studies (adult and pediatric) of MBL and severe bacterial infection, adjusting for known outcome predictors.

Main Results:

  • XA/O and O/O MBL2 genotypes exhibited the lowest MBL concentrations.
  • An MBL cutoff of 0.5 microg/mL reliably identified low-producing MBL2 genotypes (82% sensitivity, 82% specificity).
  • MBL deficiency was associated with increased mortality in severe bacterial infections (OR, 2.11) and significantly in Streptococcus pneumoniae infections (OR, 5.62) after adjustments.

Conclusions:

  • A serum MBL level of 0.5 microg/mL is defined as a reliable indicator of MBL deficiency for future studies.
  • MBL deficiency increases mortality risk in severe pneumococcal infections, underscoring the role of MBL in innate immunity.

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