Molecular, antibiogram and serological typing of Staphylococcus aureus isolates recovered from Al-Makased Hospital in East Jerusalem

Trop Med Int Health. 1998 Jul;3(7):576-83. doi: 10.1046/j.1365-3156.1998.00265.x.

Abstract

Staphylococcus aureus is a major cause of nosocomial infections and a risk in patients who have either undergone surgery or are on haemodialysis. The S. aureus infections in patients admitted to the clinical departments of Al-Makased Charitable Hospital in Jerusalem during a period of one year were investigated. Isolates included were from blood, surgical wounds, or other nonsuperficial sites. Of 63 isolates available for analysis, 46 (73.0%) expressed type 8 capsular polysaccharide; 13 (20.7%), type 5 capsular polysaccharide; only 4 isolates (6.3%) did not express type 5 or type 8 antibodies. The strains fitted in 7 different antibiogram types, with the type showing resistance only to penicillin and ampicillin prevalent in 34 out of 63 isolates (54.0%). Of the 12 methicillin-resistant S. aureus (MRSA) isolates (19.1%), 8(66.7%) possessed the type 8 capsule and 4(33.7%) the type 5 capsule. Pulsed-field gel electrophoresis of all isolates with the restriction-endonuclease enzymes Sma I revealed 34 patterns demonstrating that no single methicillin-sensitive S. aureus strain was endemic in the hospital. However, all MRSA isolates with a type 8 capsule showed identical PFGE patterns using the 2 restriction-endonuclease enzymes Sma I and SST II. Moreover, type 5 isolates showed identical patterns (one isolate differed from the rest with one band only). These data suggest and confirm the clonality of type 5 and type 8 MRSA isolates. Analysing the results of the capsular and antibiogram typing schemes in conjunction proved useful and suggested that such an analysis can be employed as a helpful epidemiological tool in hospitals with limited resources.

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Arabs
  • Bacterial Capsules / classification
  • Cross Infection / microbiology
  • DNA, Bacterial / genetics
  • Electrophoresis, Gel, Pulsed-Field
  • Genome, Bacterial
  • Genotype
  • Hospitals, General
  • Humans
  • Israel
  • Methicillin Resistance
  • Microbial Sensitivity Tests / methods
  • Microbial Sensitivity Tests / statistics & numerical data
  • Phenotype
  • Serotyping / methods
  • Serotyping / statistics & numerical data
  • Staphylococcal Infections / microbiology
  • Staphylococcus aureus / classification
  • Staphylococcus aureus / drug effects
  • Staphylococcus aureus / enzymology
  • Staphylococcus aureus / genetics
  • Staphylococcus aureus / isolation & purification*
  • beta-Lactamases / biosynthesis

Substances

  • Anti-Bacterial Agents
  • DNA, Bacterial
  • beta-Lactamases