Related Experiment Video
Updated: Jul 19, 2026
04:37
A Periprosthetic Joint Candida albicans Infection Model in Mouse
Published on: February 2, 2024
Staphylococcus aureus small colony variants in prosthetic joint infection
Parham Sendi1, Markus Rohrbach, Peter Graber
1Unit of Infectious Diseases, Basel University Medical Clinic Liestal, Liestal, CH-4410, Switzerland. sendi-pa@magnet.ch
Summary
Small colony variants of Staphylococcus aureus can cause persistent implant-associated infections. A two-stage prosthesis exchange and extended antibiotic therapy achieved successful outcomes in five patients.
Area of Science:
- Infectious Diseases
- Orthopedic Surgery
- Microbiology
Background:
- Small colony variants (SCVs) of Staphylococcus aureus are known for treatment persistence, particularly in implant-associated infections.
- SCVs can evade host defenses and standard antimicrobial treatments, leading to chronic infections.
Purpose of the Study:
- To analyze the clinical course and treatment outcomes of hip prosthesis-associated infections caused by SCVs.
- To evaluate the efficacy of a specific treatment strategy for these challenging infections.
Main Methods:
- Retrospective analysis of 5 cases of hip prosthesis infections due to SCVs.
- Inclusion of microbiological examination and transmission electron microscopy (TEM) in biopsy investigations.
- Application of a treatment algorithm involving two-stage exchange surgery and prolonged antibiotic therapy.
Main Results:
- Patients experienced treatment failures before SCV identification, despite multiple surgeries and prolonged antibiotic courses.
- TEM revealed intracellular SCVs within fibroblasts in periprosthetic tissue.
- A two-stage exchange procedure without spacer implantation, followed by 5.5-7 weeks of antibiotics, led to successful outcomes in all 5 cases.
Conclusions:
- SCVs should be suspected and actively investigated in implant-associated staphylococcal infections with poor treatment response.
- A two-stage exchange surgery with an adequate implant-free interval and targeted antimicrobial therapy is an effective strategy for SCV-related implant infections.
Related Concept Videos
01:29Staphylococcal Skin Infections
Staphylococcus aureus is a Gram-positive coccus that resides harmlessly on the skin and mucous membranes of healthy individuals. When the skin barrier is breached, it can shift from a commensal to an opportunistic pathogen. This transition is facilitated by surface adhesins, such as clumping factor B and S. aureus surface protein G (SasG), which bind to structural proteins, including loricrin and cytokeratin, in the damaged epidermis. Protein A, another key factor, binds the Fc region of...
01:25Clinical Significance of Antibiotic Resistance
Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist β-lactam antibiotics due to acquisition of the mecA gene within the staphylococcal cassette chromosome mec (SCCmec). This gene encodes penicillin-binding protein 2a (PBP2a), which impairs binding efficacy of methicillin and other β-lactams. MRSA has evolved into distinct clonal lineages impacting humans and animals alike, reinforcing its significance within the One...
01:27Streptococcal Pharyngitis
Streptococcal pharyngitis, commonly known as “strep throat,” is an acute infection of the oropharyngeal tissues caused by the Gram‑positive Group A Streptococcus (Streptococcus pyogenes). Transmission occurs primarily through respiratory droplets expelled during coughing, sneezing, or talking.Mechanisms of Host Entry and Immune EvasionUpon entering the host, S. pyogenes adheres to the mucosal epithelial cells of the pharynx via surface proteins, notably lipoteichoic acid and the antiphagocytic...
01:25Endocarditis II: Clinical Features of Infective Endocarditis
Endocarditis can present various clinical features depending on the causative organism and the patient's underlying health conditions. Initially, the clinical features of infective endocarditis develop gradually, presenting with nonspecific symptoms that can be easily mistaken for other illnesses.General SymptomsEarly symptoms of infective endocarditis are fever, chills, weakness, malaise, fatigue, and weight loss. These symptoms reflect the systemic nature of the infection and the body's...
01:30Bacterial Phylum Spirochaetes
Spirochetes, unique bacteria in the phylum Spirochaetes, are gram-negative, motile, tightly coiled, slender, and flexible. They inhabit aquatic sediments and animals, with some causing diseases like syphilis. Spirochetes are classified into eight genera based on habitat, pathogenicity, phylogeny, and characteristics.Their distinctive motility arises from endoflagella, located within the cell’s periplasm. These endoflagella anchor at the cell poles and extend along the cell length, encased by a...
01:25Mechanism of Antibiotic Resistance in MRSA
Antibiotic resistance in bacteria arises when microorganisms evolve the ability to withstand drugs designed to kill them or inhibit their growth, rendering once-effective treatments useless. This phenomenon, driven by genetic change and selection under antibiotic exposure, poses a profound threat to modern medicine. Mechanisms include drug-inactivating enzymes (e.g., β-lactamases), efflux pumps that eject antibiotics, mutations altering antibiotic targets, decreased drug uptake, and acquisition...