Related Experiment Video

Updated: Aug 3, 2026

A Murine Model of Group B Streptococcus Vaginal Colonization
10:19

A Murine Model of Group B Streptococcus Vaginal Colonization

Published on: November 16, 2016

Change in antibiotic resistance of group B streptococcus: impact on intrapartum management

W J Morales1, S S Dickey, P Bornick

  • 1Florida Perinatal Associates, Department of Biology, University of South Florida, Tampa, 33613, USA.

American Journal of Obstetrics and Gynecology
|August 24, 1999
PubMed

Insights

Group B Streptococcus antibiotic resistance to clindamycin and erythromycin has increased significantly. This rise in resistance may necessitate updates to current treatment guidelines for pregnant individuals.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Obstetrics & Gynecology

Background:

  • Intrapartum chemoprophylaxis effectively reduces group B Streptococcus (GBS) neonatal infections.
  • Penicillin-allergic patients typically receive clindamycin or erythromycin for GBS prophylaxis.
  • Emerging antibiotic resistance patterns require ongoing surveillance.

Purpose of the Study:

  • To investigate trends in antibiotic resistance among clinical isolates of group B Streptococcus.
  • To compare GBS antibiotic resistance over an 18-year period (1980-1998).

Main Methods:

  • Retrospective analysis of GBS isolates from the lower genital tract.
  • Antimicrobial susceptibility testing against ampicillin, penicillin, clindamycin, and erythromycin.
  • Comparison of resistance patterns between isolates from 1980-1993 and 1997-1998.

Main Results:

  • A significant increase in erythromycin resistance was observed between the two study periods (18% in 1997-1998 vs. 1.2% in 1980-1993; P <.001).
  • Five of the 18 erythromycin-resistant isolates in 1997-1998 were also resistant to clindamycin.
  • All tested GBS isolates remained susceptible to ampicillin and penicillin.
  • Resistant strains in 1997-1998 showed susceptibility to cephalothin.

Conclusions:

  • In vitro resistance of group B Streptococcus to clindamycin and erythromycin has increased over 18 years.
  • These findings suggest potential challenges with current GBS prophylaxis recommendations for penicillin-allergic individuals.
  • Further studies are warranted to confirm these trends and inform potential guideline modifications by the Centers for Disease Control and Prevention.
Abstract

More Related Videos

Multiplex Therapeutic Drug Monitoring by Isotope-dilution HPLC-MS/MS of Antibiotics in Critical Illnesses11:17

Multiplex Therapeutic Drug Monitoring by Isotope-dilution HPLC-MS/MS of Antibiotics in Critical Illnesses

Published on: August 30, 2018

Quadruple-Checkerboard: A Modification of the Three-Dimensional Checkerboard for Studying Drug Combinations11:15

Quadruple-Checkerboard: A Modification of the Three-Dimensional Checkerboard for Studying Drug Combinations

Published on: July 24, 2021

Related Concept Videos

Acute Pyelonephritis II: Diagnostic Studies and Management01:28

Acute Pyelonephritis II: Diagnostic Studies and Management

Introduction:For diagnosing acute pyelonephritis, a comprehensive patient history is collected to identify symptoms such as dysuria, frequent or urgent urination, flank pain, or costovertebral angle (CVA) tenderness that may suggest a kidney infection.Physical ExaminationDuring the physical examination, CVA tenderness is assessed. This involves gentle percussion over the costovertebral angle, where tenderness often indicates a kidney infection.Diagnostic TestsUrinalysis: Used to identify white...
Development of Antibiotic Resistance01:30

Development of Antibiotic Resistance

Antibiotic resistance is a major public health concern that arises when bacteria evolve mechanisms to withstand the effects of antibiotic treatments. This resistance can be intrinsic, acquired through genetic mutations, or transferred between bacteria via horizontal gene transfer. The development of antibiotic resistance poses significant challenges in treating bacterial infections and necessitates ongoing research to develop new therapeutic strategies.Intrinsic resistance occurs when bacterial...
Microbiota Modulation by Antibiotics01:21

Microbiota Modulation by Antibiotics

Antibiotics have revolutionized modern medicine by saving countless lives from bacterial infections. However, their widespread use has inadvertently harmed the delicate balance of the human gut microbiota. The gut microbiota, a complex community of bacteria, archaea, viruses, and fungi, plays a vital role in regulating metabolism, immune responses, and maintaining intestinal health. Antibiotics, especially broad-spectrum types, disrupt this ecosystem by eradicating both harmful and beneficial...
Mechanism of Antibiotic Resistance in MRSA01:25

Mechanism of Antibiotic Resistance in MRSA

Antibiotic resistance in bacteria arises when microorganisms evolve the ability to withstand drugs designed to kill them or inhibit their growth, rendering once-effective treatments useless. This phenomenon, driven by genetic change and selection under antibiotic exposure, poses a profound threat to modern medicine. Mechanisms include drug-inactivating enzymes (e.g., β-lactamases), efflux pumps that eject antibiotics, mutations altering antibiotic targets, decreased drug uptake, and acquisition...
Inhibitors of Gram-positive Cell Wall Synthesis01:23

Inhibitors of Gram-positive Cell Wall Synthesis

Bacterial cell walls are typically rigid structures composed mainly of peptidoglycan, a mesh-like polymer that provides mechanical strength and maintains cell shape. The synthesis of peptidoglycan is a crucial process in bacterial growth and serves as a primary target for many antibiotics.Mechanism of Action of Beta-Lactam AntibioticsBeta-lactam antibiotics, such as penicillin, inhibit peptidoglycan synthesis in actively growing cells. These antibiotics share a characteristic four-membered...
Clinical Significance of Antibiotic Resistance01:25

Clinical Significance of Antibiotic Resistance

Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist β-lactam antibiotics due to acquisition of the mecA gene within the staphylococcal cassette chromosome mec (SCCmec). This gene encodes penicillin-binding protein 2a (PBP2a), which impairs binding efficacy of methicillin and other β-lactams. MRSA has evolved into distinct clonal lineages impacting humans and animals alike, reinforcing its significance within the One...