Time to positivity of acute and chronic periprosthetic joint infection cultures

Introduction: A prolonged incubation time is generally recommended for diagnosing periprosthetic joint infections (PJI). However, in literature, no distinction is made between acute and chronic infections. Methods: All patients with a PJI that underwent surgical debridement between November 2015 and February 2019 with or without revision of the prosthesis were retrospectively evaluated. Synovial fluid, 5 intraoperative periprosthetic tissue samples, and the sonicated prosthesis were cultured. Results: Fifty-nine patients were analyzed, including 21 acute PJIs (33 isolates) and 38 chronic PJIs (46 isolates). In acute PJIs, all isolates grew within 5 days, while this took 11 days for chronic PJIs. Sonication fluid showed the shortest time to positivity (78% at day 2) for chronic PJIs, but no difference was observed for acute PJIs compared to tissue cultures. Conclusion: In contrast to cultures from chronic PJIs, acute PJIs do not need a prolonged incubation time and no clear benefit is observed for sonication. (C) 2020 The Authors. Published by Elsevier Inc

Computerized cyclic voltammetric detection after HPLC of the antineoplastic agents etoposide, teniposide, adriamycin and its metabolite adriamycinol in urine samples

A computerized electrochemical detection system for application after HPLC, provided with a cyclic voltammetric oxidative and reductive module, is described for the on-line qualitative determination of electroactive antineoplastic agents and metabolites in urine samples, collected from cancer patients, following intravenous administration

Nuclear imaging does not have clear added value in patients with low a priori chance of periprosthetic joint infection. A retrospective single-center experience

Background: A low-grade periprosthetic joint infection (PJI) may present without specific symptoms, and its diagnosis remains a challenge. Three-phase bone scintigraphy (TPBS) and white blood cell (WBC) scintigraphy are incorporated into recently introduced diagnostic criteria for PJI, but their exact value in diagnosing low-grade PJI in patients with nonspecific symptoms remains unclear. Methods: In this retrospective study, we evaluated patients with a prosthetic joint of the hip or knee who underwent TPBS and/or WBC scintigraphy between 2009 and 2016 because of nonspecific symptoms. We reviewed and calculated diagnostic accuracy of the TPBS and/or WBC scintigraphy to diagnose or exclude PJI. PJI was defined based on multiple cultures obtained during revision surgery. In patients who did not undergo revision surgery, PJI was ruled out by clinical follow-up of at least 2 years absent of clinical signs of infection based on MSIS 2011 criteria. Results: A total of 373 patients were evaluated, including 340 TPBSs and 142 WBC scintigraphies. Thirteen patients (3.5 %) were diagnosed with a PJI. TPBS sensitivity, specificity, and positive and negative predictive values (PPV, NPV) were 71 %, 65 %, 8 % and 98 %, respectively. Thirty-five percent of TPBS showed increased uptake. Stratification for time intervals between the index arthroplasty and the onset of symptoms did not alter its diagnostic accuracy. WBC scintigraphy sensitivity, specificity, PPV and NPV were 30 %, 90 %, 25 % and 94 %, respectively. Conclusion: Nuclear imaging does not have clear added value in patients with low a priori chance of periprosthetic joint infection

Mid-term clinical results of chronic cavitary long bone osteomyelitis treatment using S53P4 bioactive glass:A multi-center study

Introduction: Chronic osteomyelitis is a challenging condition in the orthopedic practice and traditionally treated using local and systemic antibiotics in a two-stage surgical procedure. With the introduction of the antimicrobial biomaterial S53P4 bioactive glass (Bonalive®), chronic osteomyelitis can be treated in a one-stage procedure. This study evaluated the mid-term clinical results of patients treated with S53P4 bioactive glass for long bone chronic osteomyelitis. Methods: In this prospective multi-center study, patients from two different university medical centers in the Netherlands were included. One-stage treatment consisted of debridement surgery, implantation of S53P4 bioactive glass, and treatment with culture-based systemic antibiotics. If required, wound closure by a plastic surgeon was performed. The primary outcome was the eradication of infection, and a secondary statistical analysis was performed on probable risk factors for treatment failure. Results: In total, 78 patients with chronic cavitary long bone osteomyelitis were included. Follow-up was at least 12 months (mean 46; standard deviation, SD, 20), and 69 patients were treated in a one-stage procedure. Overall infection eradication was 85 %, and 1-year infection-free survival was 89 %. Primary closure versus local/muscular flap coverage is the only risk factor for treatment failure. Conclusion: With 85 % eradication of infection, S53P4 bioactive glass is an effective biomaterial in the treatment of chronic osteomyelitis in a one-stage procedure. A major risk factor for treatment failure is the necessity for local/free muscle flap coverage. These results confirm earlier published data, and together with the fundamentally different antimicrobial pathways without antibiotic resistance, S53P4 bioactive glass is a recommendable biomaterial for chronic osteomyelitis treatment and might be beneficial over other biomaterials.</p

Long-Term Halo Follow-Up Confirms Less Invasive Treatment of Low-Grade Cartilaginous Tumors with Radiofrequency Ablation to Be Safe and Effective

Background: Radiofrequency ablation (RFA) is a minimally invasive alternative in the treatment of bone tumors. Long-term follow-up has not been described in current literature. Detailed analysis of mid- and long-term follow-up after RFA treatment for a cohort of patients with low-grade cartilaginous tumors (atypical cartilaginous tumors and enchondroma) was performed. The results, complications, and development of halo dimensions over time are presented. Methods: Data of all patients with an RFA procedure for an ACT between 2007-2018 were included. Ablation area is visible on baseline MRI, 3 months post-procedure, and is called halo. Volume was measured on MR images and compared to different follow-up moments to determine the effect of time on halo volume. Follow-up was carried out 3 months and 1, 2, 5, and 7 years after the procedure. Occurrence of complications and recurrences were assessed. Results: Of the 137 patients included, 82 were analyzed. Mean follow-up time was 43.6 months. Ablation was complete in 73 cases (89.0%). One late complication occurred, while no recurrences were seen. Halo dimensions of height, width, and depth decreased with a similar rate, 21.5% on average in the first year. Subsequently, this decrease in halo size continues gradually during follow-up, indicating bone revitalization. Conclusion: RFA is a safe and effective treatment in low-grade cartilaginous tumors with an initial success rate of 89.0%. Extended follow-up shows no local recurrences and gradual substitution of the halo with normal bone

Grip strength is strongly associated with height, weight and gender in childhood:a cross sectional study of 2241 children and adolescents providing reference values

QuestionWhat are reference values for grip strength in children and adolescents based on a large and heterogeneous study population? What is the association of grip strength with age, gender, weight, and height in this population?DesignCross-sectional study.ParticipantsParticipants were recruited from schools in the northern provinces of the Netherlands. The study included healthy children and adolescents ranging in age from 4 to 15 years.Outcome measuresAll children had their height (cm) and weight (kg) measured and were allowed a total of four attempts using the Jamar hand dynamometer: twice with each hand. Grip strength scores (kg) were recorded for the dominant and non-dominant hands.ResultsThe study population comprised 2241 children and adolescents. Reference values for both genders are provided according to age and dominance. Grip strength shows a linear and parallel progression for both genders until the age of 11 or 12, after which grip strength development shows an acceleration that is more prominent in boys.ConclusionThere is a significant difference in grip strength with each ascending year of age in favour of the older group, as well as a trend for boys to be stronger than girls in all age groups between 4 and 15 years. Weight and especially height have a strong association with grip strength in children

F-18-FDG-PET uptake in non-infected total hip prostheses

Background and purpose - F-18-fluorodeoxyglucose positron emission tomography (FDG-PET) can be used in the diagnostic work-up of a patient with suspected periprosthetic joint infection (PJI) but, due to a lack of accurate interpretation criteria, this technique is not routinely applied. Since the physiological uptake pattern of FDG around a joint prosthesis is not fully elucidated, we determined the physiological FDG uptake in non-infected total hip prostheses. Patients and methods - Patients treated with primary total hip arthroplasty (1995-2016) who underwent a FDG-PET/CT for an indication other than a suspected PJI were retrospectively evaluated. Scans were both visually and quantitatively analyzed. Semi-quantitative analysis was performed by calculating maximum and peak standardized uptake values (SUVmax and SUVpeak) by volume of interests (VOIs) at 8 different locations around the prosthesis. Results - 58 scans from 30 patients were analyzed. In most hips, a diffuse heterogeneous uptake pattern around the prosthesis was observed (in 32/38 of the cemented prostheses, and in 16/20 of the uncemented prostheses) and most uptake was located around the neck of the prosthesis. The median SUVmax in the cemented group was 2.66 (95% CI 2.51-3.10) and in the uncemented group 2.87 (CI 2.65-4.63) (Median difference = -0.36 [CI -1.2 to 0.34]). In uncemented prostheses, there was a positive correlation in time between the age of the prosthesis and the FDG uptake (r(s) = 0.63 [CI 0.26-0.84]). Interpretation - Our study provides key data to develop accurate interpretation criteria to differentiate between physiological uptake and infection in patients with a prosthetic joint.</p