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Assessing Respiratory Immune Responses to Haemophilus Influenzae
06:32

Assessing Respiratory Immune Responses to Haemophilus Influenzae

Published on: June 29, 2021

Nontypeable Haemophilus influenzae meningitis in children: phenotypic and genotypic characterization of isolates

Rita Cardines1, Maria Giufrè, Paola Mastrantonio

  • 1Department of Infectious, Parasitic and Immune-mediated Diseases, Istituto Superiore di Sanità, Rome, Italy.

The Pediatric Infectious Disease Journal
|June 29, 2007
PubMed
Abstract

Insights

Nontypeable Haemophilus influenzae (NTHi) meningitis in children shows genetic diversity. The Hia adhesin was unusually prevalent, suggesting a role in NTHi virulence for meningitis.

Area of Science:

  • Pediatric infectious diseases
  • Bacterial pathogenesis
  • Molecular microbiology

Background:

  • Routine infant immunization has decreased invasive Haemophilus influenzae type b disease.
  • Nontypeable H. influenzae (NTHi) strains are emerging as significant pathogens.
  • Understanding NTHi virulence factors is crucial for managing pediatric meningitis.

Purpose of the Study:

  • To investigate the genetic diversity and virulence factors of NTHi isolates causing meningitis in children.
  • To characterize antimicrobial resistance patterns and adhesin expression in NTHi meningitis cases.

Main Methods:

  • Analysis of 9 NTHi meningitis cases in children under 60 months.
  • Antimicrobial susceptibility testing (E-test).
  • Genetic characterization using pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST).
  • Detection of adhesins (HMW, Hia) and fimbriae via PCR and Western Blotting.

Main Results:

  • NTHi meningitis cases occurred sporadically without specific risk groups.
  • Genetic diversity was high among NTHi isolates, with no clear phylogenetic clustering.
  • The Hia adhesin was present in 5 out of 9 isolates, an unusual distribution for NTHi meningitis strains.

Conclusions:

  • NTHi meningitis in children is caused by genetically diverse strains.
  • The high prevalence of the Hia adhesin suggests its potential role in NTHi meningitis pathogenesis.
  • Further research into NTHi virulence factors is warranted.

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