Nasopharyngeal vs. Oropharyngeal Sampling for Streptococcus and Haemophilus Isolation

Strategic Insights -

The study highlights the importance of nasopharyngeal versus oropharyngeal sampling for isolating Streptococcus pneumoniae and Haemophilus influenzae from healthy and sick individuals, with the method of choice varying by age. The research, published in the Journal of Clinical Microbiology, found that nasopharyngeal (NP) sampling detected nearly 100% of Streptococcus pneumoniae isolates in children, but only 58% in mothers. Conversely, oropharyngeal (OP) sampling detected significantly more Haemophilus influenzae isolates in mothers. The study's findings suggest that culturing only one site could lead to reduced recovery of Haemophilus influenzae at all ages.

Key Takeaways:

  • Nasopharyngeal sampling yields higher rates of Streptococcus pneumoniae isolation in children, with nearly 100% detection in those aged 0-23 months.
  • Oropharyngeal sampling misses 77% of Streptococcus pneumoniae isolates in mothers, while nasopharyngeal sampling misses only 2% in this age group.
  • Haemophilus influenzae colonization increases during illness, mainly in the nasopharynx in children.
  • Culturing only one site significantly reduces the recovery of Haemophilus influenzae at all ages, with nasopharyngeal cultures alone missing 23-81% of isolates.
  • The importance of nasopharyngeal vs. oropharyngeal sampling varies by age, with significant implications for the diagnosis and treatment of respiratory infections.
  • The study's findings have important implications for the development of effective vaccination strategies and diagnostics for Streptococcus pneumoniae and Haemophilus influenzae.

Statistics:

  • 49% of Streptococcus pneumoniae isolates were missed when relying solely on oropharyngeal sampling in children aged 0-23 months.
  • 38% of Haemophilus influenzae isolates were missed when relying solely on nasopharyngeal sampling in children.
  • 81% of Haemophilus influenzae isolates were missed when relying solely on oropharyngeal sampling in mothers.
  • 58% of Streptococcus pneumoniae isolates were detected with nasopharyngeal sampling in mothers, compared to 100% in children.
  • The study analyzed cultures from 216 children aged 0-59 months.

Sources:

  • Greenberg, D. et al. (2004) Relative importance of nasopharyngeal versus oropharyngeal sampling for isolation of Streptococcus pneumoniae and Haemophilus influenzae from healthy and sick individuals varies with age. J Clin Microbiol, 42(10), 4604-4609.
  • American Society for Microbiology, 1752 N Street NW, Washington, DC 20036-2904, USA.