Streptococcus agalactiae strains isolated from cancer patients in Rio de Janeiro, Brazil

Braz J Microbiol. 2021 Mar;52(1):303-310. doi: 10.1007/s42770-020-00419-6. Epub 2021 Jan 4.


Streptococcus agalactiae is a recognized pathogen associated with infections in neonates, elderly, and immunocompromised adults, particularly those with cancer. In the present investigation, clinical-epidemiological features, multidrug resistance profiles, and virulence genes of S. agalactiae strains isolated from cancer patients were investigated. S. agalactiae capsular distribution assays demonstrated that Ia (43.6%) and V (23.6%) types were predominantly detected among 55 clinical isolates tested; only one strain (GBS1428) was capsular type III/ST-17. The fbsB and hylB genes were detected in all isolates, while the iag, lmb, and fbsA genes were detected in 94.5%, 91%, and 91% of oncological isolates, respectively. The combination of PI-1 and PI-2a was the most common (60%) among S. agalactiae strains isolated from oncologic patients. S. agalactiae strains were resistant to tetracycline (85.5%), erythromycin (9%), and clindamycin (5.5%). Norfloxacin non-susceptible was detected in 7.3% of S. agalactiae strains. Our findings reinforce the need for S. agalactiae control measures in Brazil, including cancer patients.

Keywords: Adults; Antimicrobial susceptibility; Cancer; Serotypes; Streptococcus agalactiae; Virulence factors.

MeSH terms

  • Adolescent
  • Adult
  • Anti-Bacterial Agents / pharmacology
  • Bacterial Proteins / genetics
  • Brazil / epidemiology
  • Drug Resistance, Multiple, Bacterial
  • Genotype
  • Humans
  • Microbial Sensitivity Tests
  • Middle Aged
  • Neoplasms / complications*
  • Neoplasms / microbiology
  • Streptococcal Infections / epidemiology*
  • Streptococcal Infections / microbiology*
  • Streptococcus agalactiae / drug effects
  • Streptococcus agalactiae / genetics*
  • Streptococcus agalactiae / isolation & purification*
  • Streptococcus agalactiae / pathogenicity
  • Virulence Factors / genetics
  • Young Adult


  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Virulence Factors