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Increasing resistance to penicillin in Streptococcus pneumoniae in southern Sweden

K Ekdahl1, C Kamme

  • 1Department of Infectious Diseases, Lund University Hospital, Sweden.

Scandinavian Journal of Infectious Diseases
|January 1, 1994
PubMed

Insights

Penicillin resistance in common pneumococcal types has significantly increased. In 1992, 5.0% of nasopharyngeal isolates showed intermediate resistance, a rise from 0.5% in 1980-82, indicating a growing public health concern.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Antimicrobial Resistance

Background:

  • Streptococcus pneumoniae is a leading cause of bacterial infections.
  • Penicillin has historically been a primary treatment for pneumococcal infections.
  • Monitoring antimicrobial susceptibility is crucial for effective treatment strategies.

Purpose of the Study:

  • To compare the penicillin susceptibility of prevalent pneumococcal serotypes in 1992 with data from 1980-82.
  • To identify trends in penicillin resistance among nasopharyngeal isolates.

Main Methods:

  • Isolates of 6 prevalent pneumococcal types (6, 9, 14, 15, 19, 23) were collected from nasopharynx in 1992.
  • Penicillin minimum inhibitory concentrations (MICs) were determined for these isolates.
  • Susceptibility data was compared to historical data from 1980-82.

Main Results:

  • A significant increase in intermediate penicillin resistance was observed: 19/204 isolates (9.3%) in 1992 compared to 1/194 isolates (0.5%) in 1980-82 (p < 0.001).
  • No fully resistant strains (MIC ≥ 2 mg/l) were detected.
  • Serotype 15 showed a high rate of intermediate resistance (10/31 isolates), suggesting potential clonal spread.

Conclusions:

  • Intermediate penicillin resistance in nasopharyngeal pneumococci has substantially increased in Sweden.
  • The findings highlight the emergence and spread of penicillin-tolerant pneumococcal strains.
  • Continued surveillance of antimicrobial resistance is essential for public health.

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