Characterizing biofilm formation of Staphylococcus pseudintermedius in different suture materials
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Published on: May 5, 2016
Camilla M Pesset1, Carolina O da Fonseca1, Milena Antunes1
1Laboratory of Gram-Positive Cocci, Federal Fluminense University, Biomedical Institute, Rua Professor Hernani Melo N.° 101, São Domingos, Niterói, RJ, Cep: 24210-130, Brazil.
Abstract:
Staphylococcus pseudintermedius is the primary cause of pyoderma and surgical site infection (SSI) in dogs, and biofilm formation is the main reason for persistent SSI. The presence of biofilm in medical devices can directly impact treatment. Methicillin-resistant S. pseudintermedius (MRSP) emerged rapidly in companion animals, limiting treatment options. MRSP is a public health problem since zoonotic transmission can occur. The study seeks to evaluate biofilm formation capacity via Staphylococcus pseudintermedius collected from dogs affected by topical infections, in suture materials commonly used in companion animal surgery. We tested segments of four types of sutures. Biofilm production was measured by staining with safranin and colorimetric absorbance measurement. We calculated colony-forming units (CFUs) for each type of sutures and visualized biofilm via Scanning Electron Microscopy (SEM) images. The genes associated with biofilm formation (icaA and icaD) were identified using PCR. The colorimetric tests showed that the biofilm is most abundantly formed on the cotton sutures and polyglactin 910. The ability to form biofilm on polypropylene and nylon sutures has also been demonstrated, although at varying intensities. PCR revealed the presence of the two genes (icaA and icaD) in all the isolates. We used a positive control using a reference strain and negative control without bacteria for comparisons. Suture material allowing biofilm formation makes it difficult to prevent and treat surgical site infections. Therefore, it is important to know which suture thread is more susceptible to biofilm formation by bacteria to prevent possible secondary infections at surgical sites.
Insights
Staphylococcus pseudintermedius forms significant biofilms on common dog surgical sutures, particularly cotton and polyglactin 910. This bacterial biofilm formation complicates surgical site infection treatment in canines.
Area of Science:
- Veterinary Microbiology
- Infectious Diseases
- Biomaterials Science
Background:
- Staphylococcus pseudintermedius causes pyoderma and surgical site infections (SSI) in dogs.
- Biofilm formation by bacteria is a major factor in persistent SSIs and impacts medical device efficacy.
- Methicillin-resistant S. pseudintermedius (MRSP) is a growing concern in companion animals, with zoonotic potential.
Purpose of the Study:
- To evaluate the biofilm formation capacity of Staphylococcus pseudintermedius on commonly used veterinary surgical suture materials.
- To identify suture types that promote or resist biofilm development by S. pseudintermedius.
Main Methods:
- S. pseudintermedius isolates from infected dogs were used to inoculate four types of surgical sutures.
- Biofilm formation was quantified using safranin staining and colorimetric absorbance.
- Colony-forming units (CFUs) were determined, and biofilm was visualized using Scanning Electron Microscopy (SEM).
- Genes (icaA and icaD) associated with biofilm formation were identified via PCR.
Main Results:
- Cotton and polyglactin 910 sutures showed the highest levels of biofilm formation.
- Polypropylene and nylon sutures also supported biofilm formation, but to a lesser extent.
- The genes icaA and icaD, crucial for biofilm production, were present in all tested S. pseudintermedius isolates.
- SEM confirmed bacterial biofilm presence on the suture materials.
Conclusions:
- Suture material significantly influences S. pseudintermedius biofilm formation.
- Cotton and polyglactin 910 sutures are more susceptible to biofilm development, potentially increasing SSI risk.
- Understanding suture susceptibility to biofilm is crucial for preventing and managing surgical site infections in veterinary medicine.
