Purpose. Severe osteo-articular infection can be a devastating disease causing local complications, multiple organ failure and death. The aim of this study is to highlight the potential severity and subsequent sequelae of osteo-articular infections in children and to determine causative factors leading to this devastating condition. Methods. We retrospectively report on six cases treated at two academic hospitals. We included all patients with osteo-articular infections who had multi-organ involvement. All patients had more than one joint as well as another organ involved as a direct result of the bacteraemia. All patients with single organ involvement were excluded. The patient files were recorded as part of a previously published study. Data capture included X-rays, serology for blood culture, FBC, ESR, CRP and HIV. Ultrasound of involved joints, technetium bone scans, echocardiograms and computed tomography of the brain were performed when indicated. Results. There was a delay in the diagnosis and subsequent treatment of all of these patients, mean duration 4.8 days(1 to 10) Twenty-two osteo-articular sites were involved mean 3,7 sites (2 to 6)and seventeen other organs mean 2,8 (2 to 5). The mean number of debridements or joint washouts for each patient was 4,5 (3 to 6). Four of the six cases cultured organisms: One Staphylococcus aureus, one Haemophilus influenzae and one Candida spp on tissue. Local complications included chronic osteomyelitis, physeal separation, pathological fractures and hip dislocation. There was one death in a nine year old HIV positive patient with severe multiple organ failure. Conclusion. A delay in the diagnosis and treatment of osteo-articular infection was identified as the causative factor leading to severe infection with life threatening complications. NO DISCLOSURES

Aim. Daptomycin plus fosfomycin combination therapy is a valuable strategy for treating staphylococcal osteoarticular infections. Considernig that each gram of fosfomycin contains 330 mg of sodium, electrolytic imbalance due to sodium overload could pose safety issues, especially in the cardiopatic patients and/or in the frail elderly. The aim of this study was to compare the efficacy of using reduced vs. standard daily dose fosfomycin in combination with daptomycin in a cohort of patients with osteoarticular infections. Method. This analysis included adult patients with osteoarticular infections admitted to the Infectious Diseases Unit of our University hospital in the period Nov 2022 – Feb 2024 and who were treated with daptomycin (8-10 mg/kg/daily) plus 24h-continuous infusion (CI) fosfomycin at the standard-dose of 16 g daily (standard-dose group) or at the reduced-dose of 8-12 g daily (reduced-dose group). All the patients underwent therapeutic drug monitoring (TDM) of fosfomycin for granting a pharmacodynamic target attainment of 24h-area under the concentration-time curve over minimum inhibitory concentration (AUC24h/MIC) >95 against Staphylococcus aureus with an MIC value up to 32 mg/L and of 70%t>MIC. Estimated glomerular filtration rate (eGFR) was assessed at each TDM session. Patient clinical outcome was assessed. Results. The standard- and the reduced-dose groups included 43 (29 males, 67.4%) and 21 (11 males, 52.4%) patients, respectively. No differences in median age (54 vs. 63 years, p=36), weight (80 vs. 76 kg, p=0.13) and type of diagnosis [prosthetic joint infections (16 vs. 29, p=0.38), osteomyelitis (2 vs. 9, p=0.72), septic arthritis (3 vs. 3, p=0.39) and spondilodiscitis (0 vs. 2, p=1.0)] were observed between the two groups. Median eGFR was similar in the standard vs. the reduced-dose group (109 vs. 98 mL/min/1.73m2, p=0.004). In the reduced-dose group, CI fosfomycin was administerd at 8 and 12 g/daily in 12 and 9 patients, respectively. There was no difference between the standard- and reduced-dose groups in attainment of the pharmacodynamic targets of AUC24h/MIC>95 (41/43 vs. 20/21, p=1.0), of 70%t>MIC (43/43 vs. 21/21 p=1.0) and of clinical cure (39/43 vs. 19/21, p=1.0). Conclusions. Combination therapy of 8-10 mg/kg/daily daptomycin plus 8-12 g/daily CI fosfomycin may be as effective as that of 8-10 mg/kg/daily daptomycin plus 16 g/daily CI fosfomycin. The fosfomycin reduced-dose strategy allows to decrease the daily sodium load by 25-50% compared to the standard dose, thus reducing the risk of cardiac adverse events. TDM may be a valuable strategy for individualizing fosfomycin dose in patients with osteoarticular infections

Aim. Fungal orthopaedic infections most commonly affect people with complex surgical histories and existing comorbidities. Recurrence and re-infection rates are high, even with optimal surgical and systemic antifungal treatment. AmBisome liposomal amphotericin B has been suggested for local antifungal therapy, as an adjunctive treatment for fungal osteoarticular infections. Few case series have examined its clinical use when combined with polymethylmethacrylate cement PMMA), or with absorbable local antibiotic carriers. We aimed to evaluate the clinical use of local antifungal therapy with AmBisome liposomal amphotericin B (ABlaB), including tolerated doses, serious adverse events, and treatment outcomes. Method. A retrospective cohort of all patients treated with local antifungal therapy with ABlaB between January 2016 and January 2021 in a specialist orthopaedic hospital was identified using pharmacy records. Renal function, serious adverse events during treatment, surgical outcomes including spacer fracture and infection recurrence, were identified from electronic clinical records. The project was approved by the Institutional Review Board (clinical audit 6871). Results. 13 operations involving local antifungal therapy with ABlaB, in 12 patients, were identified. Eleven were infected with Candida species and one with Aspergillus. Mean follow-up was 22 months (range 4–46). Ten first stage arthroplasty revisions, 2 second stage arthroplasty revisions, and one debridement and removal of metalwork for fracture-related infection were performed. Locally implanted doses of ABlaB ranged from 100mg to 3600mg (50–400mg per 40g mix of PMMA). Six patients received ABlaB in absorbable antibiotic carriers containing calcium sulphate. This was noted to delay carrier setting. Patients were also given systemic antifungal therapy. No patients experienced serious adverse events related to toxicity from local antifungal therapy with ABlaB. There were no spacer fractures. Overall treatment success was 54% at final follow-up, although there were no recurrent fungal infections identified in patients experiencing treatment failure. Conclusions. Local antifungal therapy with liposomal amphotericin B, when combined with surgery and systemic therapy, appears to be a safe and well tolerated intervention in the management of complex fungal osteoarticular infections

Staphylococcus aureus osteo-articular infections (OAI) are frequently accompanied by blood stream infections (BSI) diagnosed by positive blood culture (BC). Microbiological protocols in adults advise prolonged intravenous antibiotics and repeat BC 48-hourly in the presence of a BSI, however evidence to support the systematic employment of these guidelines in paediatric patients is lacking. We aimed to determine whether there was an increased incidence of orthopaedic and systemic complications in patients with s aureus BSI, and whether a shorter duration of intravenous antibiotics was associated with the development of complications. Following ethical approval, the departmental surgical database was searched for patients that underwent surgery for acute OAI over a 5-year period. Patients with no sample taken for BC were excluded, as were those with other or no organisms identified from any site. Demographic and clinical data were captured, including duration of IV antibiotics and development of complications. Statistical significance was set at p<0.05. Following exclusions, 44 patients with a median age of 85 months remained to be analysed. Thirty patients (68%) had a positive BC. A positive BC was associated with a higher rate of systemic complications (p=0.026) but not orthopaedic complications (p=0.159). Patients who had developed any complication had a significantly longer duration of IV antibiotic treatment compared to those without complications (p<0.001). The presenting CRP levels were significantly higher in patients that developed complications (p=0.004). Patients with staphylococcal BSI in association with an OAI are at increased risk of developing systemic complications. In our cohort, a shorter duration of antibiotic use was not associated with the development of complications, which does not support the systematic use of long courses of IV antibiotics in s aureus BSI. Further research will be required to determine the ideal protocol for these patients

Osteoarticular infections (OAI) are a common cause of morbidity in children, and as opposed to adults is usually caused by haematogenous spread. The bacteriology of OAI in children is not well described in the South African context, therefore this study was designed to determine the bacteriology of OAI in our population. All patients that underwent surgery for the treatment of OAI over a 3-year period were identified and those with positive cultures where organisms were identified from tissue, pus, fluid or blood were included. Duplicate cultures from the same patient were excluded if the organism and antibiotic susceptibility profile was the same. Patients were categorised according to age and class of infection (Septic arthritis, acute osteomyelitis, fracture related infection, post-operative sepsis and chronic osteomyelitis) and organisms were stratified according to these categories. We identified 132 organisms from 123 samples collected from 86 patients. Most cultured organisms were from children older than 3-years with acute haematogenous septic arthritis, osteomyelitis, or both. Methicillin sensitive Staphylococcus aureus accounted for 56% (74/132) of organisms cultured. There were no cases of MRSA. The Enterobacterales accounted for 17% (22/132) of organisms cultured, mostly in the fracture related and post-operative infection groups. Of these, 6 each were extended spectrum B-lactamase producers and AmpC producers. There were no carbapenemase producing Enterobacterales. Kingella kingae was not isolated in any patient. Methicillin sensitive S. aureus is the most common infecting organism in paediatric OAI and an anti-staphylococcal penicillin such as cloxacillin or flucloxacillin is the most appropriate empiric treatment for haematogenous OAI in our environment. In fracture related or post-operative infections, Enterobacterales were more frequently cultured, and treatment should be guided by culture and susceptibility results

Aim. To evaluate the bacterial counts of sonicatied implants in patients with osteoarticular infections. Various studies have demostrated the usefulness of sonication of retrieved implants in order to provide an accurate microbiological diagnosis. Although cutoff values for original sonicate counts have been established, the use of centrifugation may influence these values. Method. A retrospective, single-center study, including sonication fluid samples from implants removed between January 2011 and October 2023, was performed. Patients were diagnosed with implant-associated infection based on the criteria available at the time of diagnosis. Osteoarticular implants were sonicated following the protocol described by Esteban et al. Sonicated fluid was centrifuged for 20 minutes at 3000 x g, and the sediment was resuspended in 5 mL of phosphate buffer solution. Ten µl of the sample were streaked onto each medium for quantitative culture. Bacterial counts exceeding 100,000 CFU/mL were considered as 100,000 CFU/mL for statistical analysis. Results. The study included 457 sonication fluid samples. Of these, 316 samples were from patients with prosthetic joint infection (PJI), with 26.3 % diagnosed with acute PJI and 73.7 % with chronic PJI. Additionally, 141 samples were from patients with osteosynthesis infection. The median CFU/ml in the sonication fluid was 40,000 CFU/mL (IQR 1,000 CFU/mL-100,000 CFU/mL). No statistically significant difference was observed between the different types of implants (prosthesis vs. osteosynthesis, p=0.218). A trend of higher counts was noted for acute PJI compared to chronic PJI (р=0.052). Most infections were monomicrobial, but 16.2% were polymicrobial. Statistically significant higher bacterial counts were observed in polymicrobial infections compared to monomicrobial infections (р<0.005). Among monomicrobial infections, no differences were found between Gram-negative and Gram-positive microorganisms (р=0.416). No differences were also found between joints (knee vs. hip) (p=0.353). Conclusions. Significant variability was observed in the number of colonies detected in all samples, regardless of the type of implant, the number of microorganisms or the species identified. Higher counts were detected in polymicrobial infections, and a trend was also noted for higher counts in acute infections

Aim. dalbavancin, a lipo-glycopeptide antibiotic effective against Gram-positive bacteria (including methicillin-resistant Staphylococcus aureus), allows extended dosing interval due to its peculiar pharmacokinetics. Despite being registered for treatment of acute skin infections, off-label use has shown promise in various settings, particularly in osteo-articular infections. This study aims to assess dalbavancin's pharmacological efficacy and its safety and clinical success in patients treated according to personalized schedules guided by Therapeutic Drug Monitoring (TDM), particularly in long-term therapies. Methods. non-interventional, retrospective, single-center pharmacological study. We included adult patients with at least one dalbavancin TDM determination from July 1, 2022 to February 1, 2024 and treated with outpatient parenteral antimicrobial therapy. We recorded dalbavancin trough concentration (Cmin) and its peak concentration (Cmax) and employed log-linear regression models to predict the timing of dalbavancin dosing, aiming to sustain Cmin levels above 4 or 8.04 mg/L, according to recent literature. Data regarding index infections, patients’ characteristics, outcomes, and adverse events were also collected. Results. we included 32 patients, whose clinical and microbiological characteristics are depicted in Table 1. Regarding the primary outcome, 132/134 (98.5%) trough concentration was >4 mg/L, while 112/134 (83.6%) was >8.04 mg/L. For the secondary outcomes, 2/32 patients experienced an adverse event correlated to dalbavancin: (i) exanthema one week after the start of therapy and (ii) exanthema, conjunctivitis, angioedema, and nausea one month after the start of therapy. Moreover, we observed 4/32 clinical unsuccess (one failure during treatment, one relapse after the end of therapy, one switch to another antibiotic, and one isolation of non-susceptible microorganism). Conclusions. a TDM-based approach with the use of a log-linear regression model allows a more precise timing of dalbavancin administration by maintaining sufficient concentration of circulating drugs. This approach is promising for infections requiring a long-term treatment, such as orthopedic infection where source control is not possible. For any tables or figures, please contact the authors directly

Osteomyelitis and septic arthritis are common pathologies in young children. Because of their skeletal immaturity, children are particularly vulnerable to orthopaedic complications, including limb-length discrepancies, angular deformities, chondrolysis, etc. The primary objective of this study was to review the clinical follow up and outcomes of paediatric patients diagnosed with osteoarticular infections. The secondary purpose was to look for significant differences in the clinical characteristics between the one with and without complications. Patients' medical charts, hospitalised between 2010 and 2016, were retrospectively reviewed. The inclusion criteria were: patients (1) aged of less than 10 years old (2) treated and followed for osteomyelitis of long bones of upper and lower extremities and/or septic arthritis (3) with at least one year of radiological follow up. The exclusion criterion was: (1) any concomitant chronic diseases. The information collected included demographic and clinical data. A late sequela was defined as a limb-length discrepancy superior to 5 mm or an abnormal articular angulation of more than 5°, or a symptomatic chondropathy. Patients were separated in two groups: with and without complications. Chi-square tests were used for categorical variables and Mann-Whitney U tests for continuous data in order to establish significant differences between both groups. Of the 401 patients with osteomyelitis and/or septic arthritis treated in our tertiary paediatric hospital over 7 years, 50 met the inclusion criteria. There were 24 girls and 26 boys. The etiological agent was identified in 56% of the cases. Staphylococcus aureus was the predominant causal pathogen (50%), followed by Kingella kingae (19.2%). The mean follow up was 780 days. Six out of 50 (12%) patients had physeal or chondrolytic complications at the latest follow-up. The only significant difference between the 2 groups was the delay between onset of symptoms and initiation of antibiotic therapy (P = 0.039). Only 12.5% of the patients were followed up at least one year. In the population of 50 skeletally immature patients without comorbidities, 12% had a sequela. The delay in initiating antibiotic treatment was significantly longer in the group with the presence of sequelae. The results of this study reveal that there were low rates of outpatient follow-up reaching more than a year after an osteoarticular infection, thus raising the question about the importance of a follow up after such a diagnosis. Twelve percent of the patients had a growth or chondrolysis complication and this might be related to the delay before initiating antibiotic treatment

Aim. There are no studies in literature that analyze the effectiveness of closed-incisional negative pressure wound therapy (ciNPWT) in the treatment of bone and joint infections (BJI). The aim of the study was to evaluate the efficacy and the safety of the application of ciNPWT in the postsurgical wound management of patients with osteoarticular infections. Method. We conducted a perspective single-center study on patients with BJI treated between 01/2022 and 10/2022 with ciNPWT dressing application at the end of the surgical procedure. All patients were treated by a multidisciplinary team (MDT) approach and operated by the same surgical equipe. Inclusion criteria were: presence of periprosthetic joint infection (PJI), fracture-related infection (FRI), osteomyelitis (OM), septic arthritis (SA) surgically treated, after which ciNPTW was applied over the closed surgical wound. 30 patients (19M, 11F) have been analyzed with mean age of 56,10±17,11 years old; BJIs were all localized in the lower limb (16 PJI, 12 FRI, 1 SA, 1 OM). Results. We considered the following clinical local pre-operative parameters: presence of fistula (10 patients, 33,33%), presence of erythema (18 patients, 60%), presence of previous flap in the incisional site (7 patients, 23,33%). In 11 cases (36,67%) more than 3 previous surgical procedures were performed in the surgical site. The following surgical procedures were performed: 8 debridement and implants removal, 7 DAIR, 3 one-stage exchange, 6 two-stage exchange, 3 spacer exchange, 3 resection arthroplasty. Nineteen patients (63,34%) showed no occurrence of any local post-operative complication (erythema, hematoma, wound breakdown, wound blister, necrosis). Seven (23,33%) patients showed the presence of one or more postoperative complications that didn't require additional surgery. We observed four (13,33%) failures, defined as the need for further surgical procedures following the onset of a local complication: two patients had a wound breakdown before wound closure and two had a recurrence of infection after an uneventfully wound closure. All failures were within the group of joint infection (PJI+SA) and were affected by a multi drug resistant pathogen. Conclusions. In our series four patients required further surgery, but only two cases were related to incisional wound problems, that is consistent with aseptic joint revision surgeries data that are available in literature (3.4%-6.9%)[1-2]. Patients affected by BJI are a group with significant high risk of failure and therefore the use of ciNPWT should be considered. However, randomized clinical trials are needed to establish the superiority of the ciNPWT dressing over the standard one

Aim. The risk of haematogenic periprosthetic joint infection (PJI) after dental procedures is discussed controversially. To our knowledge, no study has evaluated infections according to the origin of infection based on the natural habitat of the bacteria. We investigated the frequency of positive monomicrobial cultures involving bacteria from oral cavity in patients with suspected PJI compared to bone and joint infections without joint prosthesis. Method. In this retrospective study we included all patients with suspected PJI or bone and joint infection without endoprosthesis, hospitalized at our orthopaedic clinic from January 2009 through March 2014. Excluded were patients with superficial surgical site infections or missing data. Demographic, clinical and microbiological data were collected using a standardized case report form. Groups were compared regarding infections caused by oral bacteria. χ2 test or Fisher's exact test was employed for categorical variables and t-test for continuous variables. Results. A total of 1673 patients were included, of whom 996 (60%) had a suspected PJI and 677 (40%) an osteoarticular infection without joint endoprosthesis (control group). In patients with suspected PJI the median age (standard deviation) was 67 (14) years; 407 (41%) were males. The anatomic location of the prosthesis was hip in 522 (52%) patients, knee in 437 (44%), megaprostheses in 14 (1%), shoulder in 8 (1%) and other endoprosthesis in 15 (2%) patients. In 437 (44%) of PJI cases pathogen(s) were detected, 271 (62%) were monomicrobial and 166 (38%) polymicrobial. Of 996 patients with suspected PJI, 2.4% (n = 24) had monomicrobial infections caused by bacteria belonging to the normal oral flora, predominantly oral streptococci (n = 21). In contrast, only 0.4% (n =3) of the control group without joint prosthesis had monomicrobial infections caused by oral bacteria. This difference was statistically significant (p = 0.002), whereas the patient age (p = 0.058) and the anatomic location of the joint prosthesis (p = 0.622) did not have any effect on the infections due to oral bacteria. Conclusions. The incidence of infections caused by oral bacteria was significantly higher in patients with endoprosthesis than in other osteoarticular infections (2.4% versus 0.4%). This finding indicates that joint prostheses are at risk of haematogenous PJI originating from oral cavity. Future prospective studies need to determine the exact risk of haematogenic PJI caused by oral bacteria, as well as the potential of preventing these infections by antibiotic prophylaxis

Aim. Kingella kingae seems to be the most common cause of osteoarticular infections (OAI) in children under 48 months of age (1). Recent studies had shown that K. kingae is poorly susceptible to anti-staphylococcal penicillin and some isolates produce beta-lactamase (2). This led to the need for new treatment guidelines for OAI in populations in which K. kingae is frequent. Our study aimed to design a model which could predict K. kingae OAI in order to initiate appropriate empirical treatment on hospital admission. Method. We performed a retrospective cohort study in children from 1 month to 15 years old diagnosed with OAI, hospitalized between 2006 and 2018. Mann-Whitney test and Fisher's exact test were used for data analysis. The model predicting K. kingae OAI was designed using logistic regression. Results. 247 children were included in the study, 126 (51%) had osteomyelitis (OM), 83 (33.6%) septic arthritis (SA) and 38 (15.4%) combined OM and SA. The median age was 52 (IQR 20–122) months, male-to-female ratio was 1.57:1. Pathogens were isolated in 101 (40.9%) cases with the following frequency: Staphylococcus aureus (n=59), K. kingae (n=13), Streptococcus pyogenes (n=11), Streptococcus pneumoniae (n=8). Patients with K. kingae OAI had lower CRP levels compared to other pathogens (p<0.05). WBC was higher compared to S. aureus OAI (p=0.011), children with K. kingae OAI were younger than children infected with S. aureus (p<0.001) and S. pyogenes (p=0.003). Based on this information we designed a predictive model using previous parameters as predictors of outcomes. The model had a 92.3% sensitivity and a 77.5% specificity. Then, we tried to test the model's predictive power based on the treatment failure of empirical anti-staphylococcal antibiotics in the group of children with OAI without the known pathogen. In the subgroup for which the model predicted K. kingae OAI, antibiotic treatment had to be changed in 6/59 cases. It had to be changed in only 1/83 cases in the non-K. kingae group (p=0.021). Conclusions. Despite poor specificity of the model, we found it to be more important to include all K. kingae OAI, that can be then properly treated. Additionally, with good specificity we acquire good negative predictive value, which means that children, for whom the model did not predict K. kingae OAI, can be safely treated with anti-staphylococcal penicillin

Osteoarticular infections (OAI) in children provide both diagnostic and therapeutic challenges. Recent data suggest that management of OAI can be simplified with shorter treatment duration and earlier switch to oral antibiotics. The aim of the study was to evaluate management and outcome of OAI in children at our center. A retrospective review of all cases of osteoarticular infections (OAI) in children <15 years of age treated at our institution, from May, 2006 to April, 2015 was performed. Treatment duration and outcome in two periods, 2006–2011 and 2012–2015 were compared. In a 9-year period there were 164 cases (93 cases in 2006–2011 and 71 cases in 2012–2015) of OAI with 12–24 cases annualy. A male preponderance among patients was observed with a male-to-female ratio of 1,88:1. There were 86 osteomyelitis (OM) cases, 52 septic arthritis (SA) cases and 26 OM and SA cases. The majority of cases involved lower limbs. One-third of children with OAI were either active in sport and/or had a recent history of mild trauma. In 13 (8%) cases OAI developed after varicella. There were 74 microbiologically confirmed infections and the main causative agent was Staphylococcus aureus (47 cases), followed by Streptococcus pyogenes (8 cases), S. pneumoniae (5), Kingella kingae and Salmonella (3 cases, respectively). Surgical treatment was required in 46 cases, further 18 required one or multiple joint aspirations. One child with S. aureus bacteremia had endocarditis. In one child with sepsis and multiorgan failure necrosis of the femur developed and in two bone abscesses were drained 3 and 12 months after acute episode. All 3 children had Panton-Valentine leukocidin (PVL)-positive S. aureus infection. All other children recovered without permanent sequelae. When comparing treatment duration, average treatment was shorter in 2012–2015 (31,3 days) than in 2006–2011 (38,1 days, p=0,0003), particularly due to shortening of parenteral treatment (9,0 days vs. 16,1 days, p<0,0005). The outcome was similar in both periods. OAI often occur in children who engage in sports or have a history of recent trauma. The majority of infections are caused by S. aureus, which can be severe and/or complicated if the isolate is PVL-positive. Antimicrobial treatment can be shortened and early switch to oral treatment seems to be safe. In general, prognosis of OAI in children is excellent

Aim. Skeletal tuberculosis (TB) accounts for up to one third of cases of extra-pulmonary TB but comprises a minority of osteoarticular infection in areas with low TB incidence. Consequently, unexpected cases may receive surgical management targeted at non-tuberculous orthopaedic infections. This study reviewed treatment and outcomes of non-spinal osteoarticular TB to assess outcomes from modern surgical techniques. Method. All patients with a diagnosis of non-spinal osteoarticular TB between 2009–2017 from one tertiary referral centre were included. Retrospective review of surgical intervention, antibiotic treatment and outcome was conducted. Results. Fourteen patients with an average age of 48 (range 20–77) were identified; all were HIV-negative. Articular infections affected 7 patients, including one prosthetic joint infection. Osteomyelitis affecting the carpus, femur, tibia, olecranon and metatarsals was diagnosed in the remaining patients. Only 4 patients had radiological findings consistent with prior pulmonary TB, and only 3 had a history of prior TB or TB exposure. In 2 cases, symptom exacerbation was associated with local steroid injection. Diagnostic biopsy was employed in 5 cases, of whom 4 proceeded to medical management. Diagnosis was made following positive culture in 86% of cases; all TB isolates were fully sensitive. 71% of cases underwent surgical treatment according to best practice for biofilm-forming infection, including excision of osteomyelitis with local antibiotic therapy for three patients, and first-stage excision with spacer implantation for four patients. Quadruple therapy for an average of 8.5 months, range 6–12 months, was administered. Patients were followed up for a mean of 15.2 months. Half of the patients treated with surgery reported ongoing pain at 3 months and 4 patients underwent further surgery for persistent signs of infection (2 for probable persistent TB, 2 for bacterial super-infection). Conclusions. The role of surgical debridement in management of osteoarticular TB is unclear. In patients with a previous history of TB exposure a pre-operative diagnosis of TB could prevent unnecessary surgery and therefore prevent associated post-operative complications including bacterial super-infection and pain. Pre-op biopsy should therefore be considered in all patients with a history of TB exposure

Osteoarticular infections in paediatric population are primarily hematogenous in origin, although cases secondary to penetrating trauma, surgery or contiguous site are also reported. Despite being rare, numerous studies report infection relapse rates around 5 %. Osteomyelitis complications in children include septic arthritis, osteonecrosis of the bone segment, impaired growth. 7 years old male patient presented with history of traffic injury in January 2004. He sustained closed diaphyseal fracture of the right femur initially treated by elastic osteosynthesis. Four years after traffic injury he was diagnosed at our Institution of chronic femoral Osteomyelitis with positive cultures for methicillin sensible Staphylococcus aureus, requiring multiple surgical debridements and systemic antibiotic therapy. Five years follow- up the patient developed valgus deformity of his right knee (mechanical axis 11° genu valgum) with limb length discrepancy of 15 mm, intermalleolar distance of 15 cm and bone edema in external compartment of the knee (MRI). At this time the patient did not present any recurrence of septic process with normalization of laboratory parameters (ESR and CRP) and clinically asymptomatic. In February 2014, at the end of growth, a distal femoral varus osteotomy was used to treat valgus knee malalignment. Medial closing wedge osteotomy was performed satisfactorily using Tomofix® Osteotomy System (DePuySynthes). 18 months follow- up after varus osteotomy the patient progressed satisfactorily without pain and a normal function of his right knee. Correction limb length discrepancy was achieved (5 mm) with a normal alignment of his right limb (mechanical axis 3° genu valgum). Although Osteomyelitis is not very frequent in children population, its treatment requires not only prolonged antibiotic therapy but also multiple surgical debridements. We recommend monitoring over a long period of time children affected with Osteomyelitis in order to prevent and treat correctly impaired growth

Introduction. A previous study in South Africa showed the prevalence of HIV related osteo-articular sepsis in children to be around 20% with a high prevalence of Streptococcus pneumoniae (38%) in HIV positive patients. This initial study was conducted at the same time that the polyvalent S pneumoniae vaccine was introduced to the EPI in South Africa (2009). The aim of the current study was to review the epidemiology of osteo-articular infections at two hospitals after the introduction of this vaccine. Methods. A retrospective review of patients presenting to two hospitals, between July 2009 and January 2013, with acute osteo-articular sepsis and pus at arthrotomy. The NHLS laboratory results were reviewed for microscopy, culture and sensitivity as well as white cell count (WCC), C reactive protein (CRP) and erythrocyte sedimentation rate (ESR). Results. A total of 100 cases of acute osteo-articular sepsis were identified during this period. The prevalence of HIV was 15%. The most common bacterial isolate was Staphylococcus aureus (22%). There were no Streptococcus pneumoniae isolates grown in either of the two groups. There was no difference in the WCC, CRP and ESR between the HIV negative and positive groups. Conclusion. We have seen a dramatic shift in the bacteriology in paediatric patients with osteo-articular sepsis since the original study in 2009. The incidence of HIV in our study population has declined. This may be due to the introduction of mother to child transmission programmes and increased use of anti-retrovirals. Staphylococcus aureus is now the most common isolated organism in patients with osteo-articular sepsis, regardless of HIV status. The empiric antibiotic therapy of choice in paediatric patients with osteo-articular sepsis remains Cloxacillin. NO DISCLOSURES

Prosthetic implants, periprosthetic and osteoarticular tissues are specimens of choice for diagnosis of bone and joint infections including prosthetic joint infections (PJIs). However, it is widely known that cultures from prostheses and tissues may fail to yield microbial growth in up to one third of patients. In the recent past, treatment of prosthetic implants have been optimized in order to improve sensitivity of microbiological cultures, while less attention has been addressed to tissue samples. For these latter homogenization is considered the best procedure, but it is quite laborious, time-consuming and it is not always performed in all laboratories. Dithiothreitol (DTT) has been proposed as an alternative treatment to sonication for microbiological diagnosis of PJIs. In this study, we evaluated the applicability of MicroDTTect treatment, a closed system developed for transport and treatment of tissues and prosthetic implants with DTT. For evaluation of applicability of MicroDTTect to tissue specimens, samples (tissues and, in case of PJI, prosthetic implants) from 40 patients (12 PJIs and 5 osteomyelitis and 23 not-infected) were evaluated. MicroDTTect system consists of a sterile plastic bag containing a reservoir which allows for release of a 0.1% (v:v) DTT solution, once the sample is placed into the bag. Comparison of MicroDTTect treatment of prostheses with sonication included samples from 30 patients (14 with aseptic loosening of the prosthesis and 16 with PJIs). Of two tissue samples from the same region, one was placed into MicroDTTect bag and the other was collected in a sterile container with addition of sterile saline. After agitation and centrifugation of the eluate, aliquots of the pellets were plated on agar plates and inoculated into broths which were incubated for 48 hrs and 15 days, respectively. Treatment of prosthetic implants with MicroDTTect showed a higher specificity and sensitivity than sonication (specificity 92.8% vs 85.7%; sensitivity: 87.5% vs 75.0 % DTT vs sonication). When used for tissue treatment, MicroDTTect showed a sensitivity of 82.3% and a specificity of 97% which were higher than that observed when saline was used (sensitivity: 64.7%; specificity 91%). Treatment of tissues and prosthetic implants with MicroDTTect may be a practicable strategy to improve microbiological diagnosis of osteoarticular infections, reducing sample manipulation and therefore limiting sample contamination. Moreover, use of MicroDTTect does not require dedicated instrumentation, and is time and cost saving

Aims

Orthopaedic infection is a potentially serious complication of elective and emergency trauma and orthopaedic procedures, with a high associated burden of morbidity and cost. Optimization of vitamin D levels has been postulated to be beneficial in the prevention of orthopaedic infection. This study explores the role of vitamin D in orthopaedic infection through a systematic review of available evidence.