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Published on: January 2, 2017

In vitro activity of thiamphenicol against multiresistant Streptococcus pneumoniae, Haemophilus influenzae and

A Marchese1, E A Debbia, E Tonoli

  • 1Institute of Microbiology, University of Genoa, Italy. anna.marchese@unige.it

Journal of Chemotherapy (Florence, Italy)
|February 14, 2003
PubMed

Insights

Thiamphenicol demonstrates potent in vitro activity against antibiotic-resistant bacteria, including pneumococci and MRSA. This chloramphenicol derivative shows efficacy comparable to other key antibiotics, offering a viable option for treating difficult-to-treat infections.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Pharmacology

Background:

  • Thiamphenicol, a chloramphenicol derivative, exhibits a comparable spectrum of activity against multiresistant pathogens with improved tolerability.
  • Antibiotic resistance in pathogens like Streptococcus pneumoniae and Methicillin-resistant Staphylococcus aureus (MRSA) poses a significant clinical challenge.

Purpose of the Study:

  • To evaluate the in vitro activity of thiamphenicol against antibiotic-resistant and invasive strains of Streptococcus pneumoniae and MRSA.
  • To assess the bactericidal activity and post-antibiotic effect (PAE) of thiamphenicol on key bacterial pathogens.

Main Methods:

  • In vitro susceptibility testing of thiamphenicol and 11 comparator drugs against 397 pneumococcal and 52 MRSA isolates.
  • Determination of bactericidal activity against Haemophilus influenzae.
  • Assessment of the post-antibiotic effect on Streptococcus pneumoniae, H. influenzae, Staphylococcus aureus, and Escherichia coli.

Main Results:

  • Thiamphenicol and chloramphenicol were potent non-beta-lactam agents against invasive pneumococci, comparable to vancomycin and rifampin.
  • Phenicol activity surpassed cefotaxime, ceftriaxone, and imipenem against high-level penicillin-resistant pneumococci.
  • Thiamphenicol and chloramphenicol showed significant activity against MRSA, including vancomycin-intermediate S. aureus (VISA) strains, and demonstrated a notable PAE on all tested pathogens.

Conclusions:

  • Thiamphenicol exhibits significant in vitro activity against challenging, multiply resistant bacterial pathogens.
  • The findings support thiamphenicol's potential as a therapeutic option for infections caused by antibiotic-resistant bacteria.
  • Further clinical investigation is warranted to confirm the efficacy and safety of thiamphenicol in treating resistant infections.

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