Revision of total knee replacement (TKR) secondary to raised cobalt levels: should this be considered in the painful TKR patient?

A 63-year-old woman was referred to the specialised knee revision clinic with ongoing knee pain after total knee replacement. She incidentally had cobalt and chromium levels measured. These were seen to be elevated. Comprehensive assessment and investigation did not identify any other source of cobalt or chromium. Aseptic loosening of the knee was diagnosed, and the knee was revised. At the time of surgery, the tissue was seen to be darkened consistent with metallosis. Multiple samples excluded infection on extended cultures. Aspirated fluid showed that periprosthetic fluid had elevated cobalt levels. The knee was successfully revised with good symptomatic outcome and significantly, over the course of several months post-revision, the cobalt and chromium levels returned to normal.

Study of Inflammatory and Infection Markers in Periprosthetic Fluid: Correlation with Blood Analysis in Retrospective and Prospective Studies

Background. Surgical site infection represents the most severe complication in prosthetic breast reconstruction. Risk profiling represents a useful tool for both clinicians and patients. Materials and Methods. In our hospital, 534 breast reconstructions with tissue expander implants, in 500 patients, were performed. Several clinical variables were collected. In our study, we evaluated the different inflammatory markers present in the periprosthetic fluid and we compared them with the ones present in plasma. Results. The surgical site infection rate resulted to be 10.5%, and reconstruction failed in 4.5% of the cases. The hazard ratio for complications was 2.3 in women over 60 (CI: 1.3-4.07; p = 0.004 ), 2.57 in patients with expander volume ≥ 500 cc (CI: 1.51-4.38; p < 0.001 ), 2.14 in patients submitted to previous radiotherapy (CI: 1.05-4.36; p < 0.037 ), and 1.05 in prolonged drain use (CI: 1.03-1.07; p < 0.001 ). 25-OH, PCT, and total protein were less concentrated, and ferritin and LDH were more concentrated in the periprosthetic fluid than in plasma ( p < 0.001 ). CRP ( p = 0.190 ) and β-2 microglobulin ( p = 0.344 ) did not change in the two fluids analyzed. PCT initial value is higher in patients who underwent radiotherapy, and it could be related to the higher rate of their postoperative complications. Patients with a tissue expander with a volume ≥ 500 cc show an increasing trend for CRP in time ( p = 0.009 ). Conclusions. Several risk factors (prolonged time of drains, age older than 60 years, and radiotherapy) have been confirmed by our study. The study of markers in the periprosthetic fluid with respect to their study in plasma could point toward earlier infection detection and support early management.

Periprosthetic Fluid Analysis in the Diagnosis of Breast Implant Infections Using Cell Count and Differential

Background One of the most devastating complications following implant-based breast reconstruction is periprosthetic infection. Making a prompt and accurate diagnosis has been a challenge as plastic surgeons are limited by nonspecific systemic markers of infection, clinical examination findings, or imaging modalities. Objectives The aim of this study is to evaluate the use of periprosthetic fluid using cell count and differential as an aid in the diagnosis of infection. Methods This is a retrospective chart review. The authors selected patients who underwent breast reconstruction and had periprosthetic fluid analysis during the previous 10 years based on CPT 89051 (cell count and differential, body fluid). Only patients with clinical concerns for infection were included (cellulitis, fever, etc.); all others were excluded. Results A total of 54 samples were included in the study. Twenty-seven samples were associated with periprosthetic breast infections based on positive cultures or intraoperative findings consistent with infection. On fluid analysis, those with infection had a significantly higher neutrophil percentage (84.2% vs 19.3%, P &lt; 0.0001). A cutoff value of 77% neutrophils had a sensitivity of 89% and a specificity of 93% in diagnosing infection. Delayed treatment in patients with high neutrophil percentage was associated with poorer outcomes. Lastly, there was a strong correlation between higher neutrophil percentage and increased rate of capsular contracture. Conclusions Early and accurate diagnosis of periprosthetic breast infections can lead to earlier treatment and potentially improved the outcomes. Aspiration and analysis of periprosthetic fluid for neutrophil percentage can be a reliable method to guide clinical decision making. Level of Evidence: 3

Open Conversion after Aortic Endograft Infection Caused by Colistin-Resistant, Carbapenemase-Producing Klebsiella pneumoniae

A 62-year-old man presented with fever, abdominal pain, and malaise 13 months after emergency endovascular aortic repair. Computed tomographic angiograms showed a periprosthetic fluid and gas collection, so infection was diagnosed. Open conversion was performed, involving endograft explantation and in situ aortic reconstruction. Cultures and the explanted prosthesis were positive for carbapenemase-producing Klebsiella pneumoniae, resistant to colistin. Because of the sparse data on endograft infections caused by this pathogen, we placed the patient on an empiric double-carbapenem regimen for 4 weeks. Symptomatic recovery occurred after 21 days. On the 30th day, we deployed a stent to treat a new pseudoaneurysm. Three years later, the patient had no signs of persistent or recurrent infection. We think that this is the first report of aortic endograft infection caused by colistin-resistant, carbapenemase-producing K. pneumoniae.

Multisite Infection withMycobacterium abscessusafter Replacement of Breast Implants and Gluteal Lipofilling

Introduction. Medical tourism for aesthetic surgery is popular. Nontuberculous mycobacteria (NTM) occasionally cause surgical-site infections. As NTM grow in biofilms, implantations of foreign bodies are at risk. Due to late manifestation, infections occur when patients are back home, where they must be managed properly.Case Report. A 39-year-old healthy female was referred for acute infection of the right gluteal area. Five months before, she had breast implants replacement, abdominal liposuction, and gluteal lipofilling in Mexico. Three months postoperatively, implants were removed for NTM-infection in Switzerland. Adequate antibiotic treatment was stopped after seven days for drug-related hepatitis. At entrance, gluteal puncture for bacterial analysis was performed. MRI showed large subcutaneous collection. Debridement under general anaesthesia was followed by open wound management. Total antibiotic treatment was 20 weeks.Methods. Bacterial analysis of periprosthetic and gluteal liquids included Gram-stain plus acid-fast stain, and aerobic, anaerobic and mycobacterial cultures. Results. In periprosthetic fluid,Mycobacterium abscessus, Propionibacterium, andStaphylococcus epidermidiswere identified. The sameM. abscessusstrain was found gluteally. The gluteal wound healed within six weeks. At ten months’ follow-up, gluteal asymmetry persists for deep scarring.Conclusion. This case presents major complications of multisite aesthetic surgery. Surgical-site infections in context of medical tourism need appropriate bacteriological investigations, considering potential NTM-infections.