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Updated: Dec 11, 2025
Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
Published on: May 8, 2013
Incidence and characteristics of methicillin-resistant coagulase-negative Staphylococcus aureus in peritoneal
Carlos Henrique Camargo1,2,3, Maria de Lourdes Ribeiro de Souza da Cunha4, Jacqueline Costa Teixeira Caramori5
1Department of Internal Medicine, Botucatu Medical School, Sao Paulo State University, Botucatu, São Paulo, Brazil. carlos.camargo@ial.sp.gov.br.
Purpose:
Peritonitis is a serious complication of peritoneal dialysis and coagulase-negative Staphylococcus (CNS) is the most frequent cause of peritoneal dialysis (PD)-infections in many centers. This study aimed to investigate the molecular epidemiology of CNS isolated from PD-peritonitis in a Brazilian single center, focusing on the genetic determinants conferring methicillin resistance.
Methods:
Bacterial strains were isolated from peritoneal fluid of patients presenting PD-peritonitis, identified by phenotypic and molecular methods, and those identified as CNS were submitted to mecA detection, SCCmec, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST).
Results:
Over the 18-year period of this study (1995-2011), a total of 878 peritonitis episodes were diagnosed in this unit, 115 were caused by coagulase-negative staphylococci of which 72 by Staphylococcus epidermidis. mecA gene was detected in 55 CNS (47.8%), more frequently on the more recent years. SCCmec type III was the most frequent cassette, followed by SCCmec type IV and SCCmec type II. A diverstity of pulsotypes was observed among the S. epidermidis isolates, but five clusters (based on the 80% cutoff) were identified. Diversified sequence types (ST02, ST05, ST06, ST09, ST23, ST59 and ST371) were detected.
Conclusions:
Detection of SCCmec type III among coagulase-negative Staphylococcus underscores the role of hospital environments as potential source of methicillin-resistant Staphylococcus causing peritonitis in PD patients.
Insights
Coagulase-negative Staphylococcus (CNS) frequently causes peritonitis in peritoneal dialysis (PD) patients. This study found methicillin resistance in CNS strains, with SCCmec type III being most common, highlighting hospital environments as a source of infection.
Area of Science:
- Infectious Diseases
- Microbiology
- Nephrology
Background:
- Peritonitis is a significant complication of peritoneal dialysis (PD).
- Coagulase-negative Staphylococcus (CNS) is a leading cause of PD-related peritonitis globally.
- Understanding the genetic basis of antibiotic resistance in these pathogens is crucial for effective treatment.
Purpose of the Study:
- To investigate the molecular epidemiology of CNS causing PD-peritonitis in a Brazilian center.
- To identify genetic determinants of methicillin resistance in these CNS isolates.
- To analyze trends in resistance over an 18-year period.
Main Methods:
- Isolation and identification of CNS from PD peritonitis patient samples.
- Detection of the mecA gene conferring methicillin resistance.
- Characterization of SCCmec types, pulsed-field gel electrophoresis (PFGE), and multilocus sequence typing (MLST).
Main Results:
- Over 18 years, 115 CNS peritonitis cases were identified, predominantly Staphylococcus epidermidis.
- Methicillin resistance (mecA gene) was detected in 47.8% of CNS isolates, increasing over time.
- SCCmec type III was the most prevalent resistance cassette, followed by types IV and II. Diverse pulsotypes and sequence types were observed.
Conclusions:
- The prevalence of SCCmec type III in CNS isolates suggests hospital environments are a significant source of methicillin-resistant Staphylococcus causing peritonitis in PD patients.
- Molecular typing revealed genetic diversity among causative agents.
- Findings emphasize the need for infection control measures targeting hospital-acquired pathogens in PD settings.
