Related Experiment Videos
Sequential analysis of staphylococcal colonization of body surfaces of patients undergoing vascular surgery
M F Levy1, D D Schmitt, C E Edmiston
1Department of Surgery, Medical College of Wisconsin, Milwaukee 53226.
Abstract:
Slime-producing coagulase-negative staphylococci are pathogens in vascular surgery by virtue of their ability to adhere to and persist on prosthetic graft material. Inguinal and abdominal skin sites were cultured in 41 patients upon hospitalization, and slime production and antimicrobial susceptibility were assessed in all recovered staphylococcal isolates. Twenty-one patients eventually underwent lower-extremity revascularization. In the operative population, cultures were also obtained on the day of surgery and fifth postoperative day. All 21 patients received perioperative cefazolin. Of 327 coagulase-negative staphylococci recovered, Staphylococcus epidermidis (47%), S. haemolyticus (21%), and S. hominis (10%) were the predominant isolates. Slime-producing coagulase-negative staphylococci were recovered from 17 of 21 patients at admission but only from 8 of 21 patients on day 5 postoperation (P less than 0.05). S. epidermidis isolates demonstrated increasing multiple resistance from admission to 5 days postoperation to methicillin, gentamicin, clindamycin, erythromycin, and trimethoprim-sulfamethoxazole (P less than 0.05). All coagulase-negative staphylococcal isolates were susceptible to ciprofloxacin and vancomycin. Slime-producing capability was not associated with increased methicillin resistance for the recovered isolates. The data demonstrate that patients enter the hospital colonized with slime-producing strains of coagulase-negative staphylococci and that during hospitalization the staphylococcal skin burden shifts from a predominately susceptible to a resistant microbial population, which may enhance the importance of slime production as a risk factor in lower-extremity revascularization.
Insights
Patients admitted for vascular surgery carry slime-producing bacteria on their skin. Hospitalization increases bacterial resistance, potentially elevating risks associated with slime-producing coagulase-negative staphylococci in lower-extremity revascularization.
Area of Science:
- Medical Microbiology
- Infectious Diseases
- Surgical Infections
Background:
- Slime-producing coagulase-negative staphylococci (CoNS) are significant pathogens in vascular surgery.
- Their ability to adhere to and persist on prosthetic grafts poses a risk for infection.
- Understanding the prevalence and antimicrobial resistance of these bacteria is crucial for patient outcomes.
Purpose of the Study:
- To assess slime production and antimicrobial susceptibility of CoNS in patients undergoing lower-extremity revascularization.
- To evaluate changes in CoNS colonization and resistance patterns during hospitalization.
- To determine the association between slime production and antibiotic resistance in CoNS.
Main Methods:
- Cultured skin sites (inguinal and abdominal) from 41 patients upon hospitalization.
- Assessed slime production and antimicrobial susceptibility of recovered CoNS isolates.
- Obtained intraoperative and postoperative (day 5) cultures from 21 patients undergoing lower-extremity revascularization.
- All patients received perioperative cefazolin.
Main Results:
- Predominant CoNS isolates included Staphylococcus epidermidis (47%), S. haemolyticus (21%), and S. hominis (10%).
- Slime-producing CoNS were found in 17/21 patients on admission, decreasing to 8/21 by day 5 postoperation (P < 0.05).
- S. epidermidis exhibited increasing multiple drug resistance (methicillin, gentamicin, clindamycin, erythromycin, trimethoprim-sulfamethoxazole) from admission to day 5 (P < 0.05).
- All CoNS isolates remained susceptible to ciprofloxacin and vancomycin.
- Slime production did not correlate with increased methicillin resistance.
Conclusions:
- Patients are often colonized with slime-producing CoNS upon hospital admission.
- Hospitalization leads to a shift towards a more resistant CoNS population on the skin.
- Slime production may be an important risk factor for infections in lower-extremity revascularization procedures.