Acute osteomyelitis of the acetabulum induced by Staphylococcus capitis in a young athlete

Staphylococcus capitis: Review of Its Role in Infections and Outbreaks

In June 2021, a national incident team was formed due to an increased detection of Staphylococcus capitis in samples from hospitalised infants. Staphylococcus capitis has been known to cause outbreaks in neonatal units across the globe, but the extent of the UK spread was unclear. A literature review was undertaken to support case identification, clinical management and environmental infection control. A literature search was undertaken on multiple databases from inception to 24 May 2021, using keywords such as “Staphylococcus capitis”, “NRCS-A”, “S. capitis”, “neonate”, “newborn” and “neonatal intensive care unit” (NICU). After screening, 223 articles of relevance were included. Results show incidences of S. capitis outbreaks have frequently been associated with the outbreak clone (NRCS-A) and environmental sources. The NRCS-A harbours a multidrug resistance profile that includes resistance to beta-lactam antibiotics and aminoglycosides, with several papers noting resistance or heteroresistance to vancomycin. The NRCS-A clone also harbours a novel SCCmec-SCCcad/ars/cop composite island and increased vancomycin resistance. The S. capitis NRCS-A clone has been detected for decades, but the reasons for the potentially increased frequency are unclear, as are the most effective interventions to manage outbreaks associated with this clone. This supports the need for improvements in environmental control and decontamination strategies to prevent transmission.

Staphylococcus capitis Osteomyelitis: Case Report

This case report describes an unusual invasive infection with Staphylococcus capitis, in a child with a history of repaired congenital heart disease and an acute presentation of osteomyelitis. Coagulase-negative staphylococci are rare causes of osteomyelitis without an implanted device in the bone and, as such, should prompt evaluation for associated infections that may be contributing to the unusual presentation. Additionally, this case highlights the importance of considering methicillin heteroresistance in staphylococcal infections when the clinical course is not proceeding as expected.

Coagulase-Negative Staphylococcus Skin and Soft Tissue Infections

Coagulase-negative staphylococcus organisms may be normal flora of human skin, however these bacteria can also be pathogens in skin and soft tissue infections. A summary of skin and soft tissue infections caused by coagulase-negative staphylococcus species is provided in this review. We conducted a search of the PubMed database using the following terms: abscess, auricularis, biofilm, capitis, cellulitis, coagulase, contaminant, cyst, draining, epidermidis, felon, folliculitis, furuncle, haemolyticus, hominis, indolent, infection, lugdunensis, mecA, microbiome, negative, osteomyelitis, paronychia, saprophyticus, skin, simulans, sinus, soft, staphylococcus, systemic, tissue, virulence, virulent, and vulvar. The relevant papers, and their references, generated by the search were reviewed. Skin and soft tissue infections have been observed to be caused by many coagulase-negative staphylococcus organisms: Staphylococcus auricularis, Staphylococcus capitis, Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus hominis, Staphylococcus lugdunensis, Staphylococcus saprophyticus, and Staphylococcus simulans. Coagulase-negative staphylococcus skin infections predominantly present as abscesses and paronychia. They are most common in elderly patients or those individuals who are immunosuppressed, and tend to be broadly susceptible to antibiotic treatment. In conclusion, albeit less common, coagulase-negative staphylococcus organisms can result in skin and soft tissue infections, particularly in older and/or immunocompromised individuals. A review of the literature found that coagulase-negative staphylococcus organisms are most commonly grown in cultures of abscesses and paronychia. Therefore, coagulase-negative staphylococcal organisms should not always be considered as contaminants or normal flora, but rather as causative pathogens. They are usually susceptible to antibiotics used to treat methicillin-sensitive Staphylococcus aureus.

Staphylococcus capitis isolated from prosthetic joint infections

Further knowledge about the clinical and microbiological characteristics of prosthetic joint infections (PJIs) caused by different coagulase-negative staphylococci (CoNS) may facilitate interpretation of microbiological findings and improve treatment algorithms. Staphylococcus capitis is a CoNS with documented potential for both human disease and nosocomial spread. As data on orthopaedic infections are scarce, our aim was to describe the clinical and microbiological characteristics of PJIs caused by S. capitis. This retrospective cohort study included three centres and 21 patients with significant growth of S. capitis during revision surgery for PJI between 2005 and 2014. Clinical data were extracted and further microbiological characterisation of the S. capitis isolates was performed. Multidrug-resistant (≥3 antibiotic groups) S. capitis was detected in 28.6 % of isolates, methicillin resistance in 38.1 % and fluoroquinolone resistance in 14.3 %; no isolates were rifampin-resistant. Heterogeneous glycopeptide-intermediate resistance was detected in 38.1 %. Biofilm-forming ability was common. All episodes were either early post-interventional or chronic, and there were no haematogenous infections. Ten patients experienced monomicrobial infections. Among patients available for evaluation, 86 % of chronic infections and 70 % of early post-interventional infections achieved clinical cure; 90 % of monomicrobial infections remained infection-free. Genetic fingerprinting with repetitive sequence-based polymerase chain reaction (rep-PCR; DiversiLab®) displayed clustering of isolates, suggesting that nosocomial spread might be present. Staphylococcus capitis has the potential to cause PJIs, with infection most likely being contracted during surgery or in the early postoperative period. As S. capitis might be an emerging nosocomial pathogen, surveillance of the prevalence of PJIs caused by S. capitis could be recommended.

First report of spondylodiscitis due to vancomycin heteroresistant Staphylococcus capitis in immunocompetent host

We report a successfully treated case of spondylodiscitis and bloodstream infection due to vancomycin heteroresistant Staphylococcus capitis, in an adult immunocompetent patient with multiple antibiotics intolerance. S. capitis is rarely involved in osteomyelitis and, to our knowledge, this is the first report of vancomycin heteroresistance phenomenon in an S. capitis strain causing spondylodiscitis.

A rare case of acetabulum osteomyelitis mimicking bone sarcoma

A 57-year-old man presented to the authors' department with pain over the right hip joint over a 3-month period. External magnetic resonance imaging showed a structure in the right acetabulum that was highly suspicious for a bone sarcoma. External 3-phase bone scintigraphy substantiated the suspected diagnosis. A computer tomography-guided biopsy was performed. Microbiologic examination showed a Staphylococcus aureus strain. Histopathologic findings showed chronic fibrous osteomyelitis. Because of doubts about these findings made by radiologists, open biopsy with retrieval of bony samples from the acetabulum and hip joint puncture was repeated. At that time, the serum C-reactive protein level was 48.8 mg/dL and the white blood cell count was 5600 × 10⁶/L. Microbiologic examination showed a S aureus and a Staphylococcus epidermidis strain in both regions. Results of blood cultures were negative. Based on these findings, the decision was made to perform a septic femoral head and neck resection. After meticulous debridement, necrosectomy, and pulsatile lavage, a gentamicin and vancomycin-impregnated cement spacer was implanted. Postoperatively, systemic antibiotic treatment with cefuroxime and rifampicin was administered for 4 weeks, followed by 2 weeks of oral antibiotics. Mobilization was allowed under toe-touch bearing of the operated extremity. The further postoperative course was uneventful. Prosthesis implantation was performed after 3 months. White blood cell count and C-reactive protein values were normal at the time of surgery. Histologic and microbiologic examination of tissue samples taken intraoperatively showed no evidence of persistent infection. At follow-up after 1 year, the patient had no complaints and has no local or systemic signs of infection.

Osteomyelitis of the tibia following anterior cruciate ligament reconstruction

INTRODUCTION

Osteomyelitis following anterior cruciate ligament (ACL) reconstruction is extremely rare.

PRESENTATION OF CASE

We present a thirty year old man who presented with pain in his proximal tibia six years after ACL reconstruction. Haematological investigations were normal. He was diagnosed with osteomyelitis of his proximal tibia. He was successfully treated with washout and debridement of his tibial tunnel.

DISCUSSION

This case highlights the need to exclude osteomyelitis as a late complication of ACL reconstruction in patients with proximal tibial pain. We also report on an unusual pathogen as casue of osteomyelitis.

CONCLUSION

Osteomyelitis in a tibial tunnel can present as a late complication of ACL reconstruction, even in the presence of normal haematological investigations.