Septic arthritis of the native hip joint and septic pulmonary embolism in an adult with sickle cell trait after a complicated dental extraction.

Septic arthritis (SA) is a serious infection of the joint which can lead to irreversible destruction of the joint.We report a case of right hip SA with septic pulmonary embolism following a complicated dental extraction in a woman in her early 40s with sickle cell trait (SCT).The patient presented with severe right thigh pain and left jaw pain.Initial workup revealed raised C reactive protein and positive blood cultures. Right hip joint SA was confirmed following intraoperative joint aspiration. The patient had right hip debridement with long-term intravenous antibiotics.The incidence of SA in adults with sickle cell disease is low: 0.3% in a study in France and Brazil and 10.3% incidence of haematogenous osteoarticular infection in children with SCT in West Africa.

Outcomes of primary total hip arthroplasty following septic arthritis of the hip : a case-control study.

AIMS: Septic arthritis of the hip often leads to irreversible osteoarthritis (OA) and the requirement for total hip arthroplasty (THA). The aim of this study was to report the mid-term risk of any infection, periprosthetic joint infection (PJI), aseptic revision, and reoperation in patients with a past history of septic arthritis who underwent THA, compared with a control group of patients who underwent THA for OA. METHODS: We retrospectively identified 256 THAs in 244 patients following septic arthritis of the native hip, which were undertaken between 1969 and 2016 at a single institution. Each case was matched 1:1, based on age, sex, BMI, and year of surgery, to a primary THA performed for OA. The mean age and BMI were 58 years (35 to 84) and 31 kg/m2 (18 to 48), respectively, and 100 (39%) were female. The mean follow-up was 11 years (2 to 39). RESULTS: The ten-year survival free of any infection was 91% and 99% in the septic arthritis and OA groups, respectively (hazard ratio (HR) = 13; p < 0.001). The survival free of PJI at ten years was 93% and 99% in the septic arthritis and OA groups, respectively (HR = 10; p = 0.002). There was a significantly higher rate of any infection at ten years when THA was undertaken within five years of the diagnosis of septic arthritis compared with those in whom THA was undertaken > five years after this diagnosis was made (14% vs 5%, respectively; HR = 3.1; p = 0.009), but there was no significant difference in ten-year survival free of aseptic revision (HR = 1.14; p = 0.485). The mean Harris Hip Scores at two and five years postoperatively were significantly lower in the septic arthritis group compared with the OA group (p = 0.001 for both). CONCLUSION: There was a ten-fold increased risk of PJI in patients with a history of septic arthritis who underwent THA compared with those who underwent THA for OA with a ten-year cumulative incidence of 7%. The risk of any infection had a strong downward trend as the time interval between the diagnosis of septic arthritis and THA increased, highlighted by a 3.1-fold higher risk when THAs were performed within five years of the diagnosis being made. Cite this article: Bone Joint J 2022;104-B(2):227-234.

First case of periprosthetic joint infection due to Clostridioides difficile in China.

BACKGROUND: Clostridioides difficile usually causes intestinal infections. However, a 75-year-old lady had a periprosthetic joint infection due to this microorganism. We report a C. difficile infection of a prosthetic hip joint. Such an infection is rarely reported around the world. CASE PRESENTATION: The elder female patient presented with a 2-year history of right hip pain with movement restriction. Her right leg was shorter than another. The skin around the right hip joint was red and swollen without sinus. Her lab test result showed elevator ESR and CRP. Her X-ray film showed a massive bone defect. The patient had a total hip arthroplasty 16 years ago and had a revision 5 years ago. During this hospitalization, her cultures of the synovial fluid and tissue repeatedly grew C. difficile. She improved following two-stage revision surgery and antibiotic treatment. The patient has no recurrence of infection after a one-year follow-up. CONCLUSION: A rapid and accurate sample collection is significant for culture results, making an outstanding contribution to the successful treatment.

Early clinical outcomes of one-stage total hip arthroplasty for the treatment of advanced hip tuberculosis.

OBJECTIVE: To investigate the clinical efficacy of one-stage total hip arthroplasty (THA) for treating the advanced hip tuberculosis. METHODS: A retrospective study was conducted from July 2013 to June 2018, including 19 patients with advanced hip tuberculosis. All patients underwent total hip arthroplasty through posterior approach, and the surgical efficacy was evaluated. RESULTS: Nineteen patients were followed up from 24 months to 48 months, the mean follow-up were 32.1 months. All the incisions healed in grade A. There were no aseptic loosening, dislocation or recurrence of hip tuberculosis after operation. At the last follow-up, the Harris score of the patients was (89.3 ± 6.7), which was significantly higher than (38.2 ± 10.5) of the patients before operation (P < 0.05); the flexion-extension range of motion was (93.6° ± 12.1°), which was significantly larger than (38.2° ± 10.5°) of the patients before operation (P < 0.05). CONCLUSION: The one-stage total hip arthroplasty with regular antituberculosis treatment can attain satisfactory clinical efficacy in the treatment of advanced hip tuberculosis, which can relieve the joint pain and improve the joint function, without recurrence of hip tuberculosis.

Low Reinfection Rates But a High Rate of Complications in THA for Infection Sequelae in Childhood: A Systematic Review.

BACKGROUND: Childhood hip infections can result in serious sequelae during adulthood, including persistent pain, functional limitations, and premature THA. When THA is performed in patients who had hip joint infections during childhood, surgeons surmise these arthroplasties are at an increased risk of complications and incomplete recovery. However, the degree to which this is true is not well characterized and has varied across a large number of small, retrospective studies. QUESTIONS/PURPOSES: (1) What proportion of THAs performed in patients who had pediatric septic arthritis result in periprosthetic joint infection? (2) What are the Harris hip scores associated with these reconstructions? (3) What proportion of these patients develop complications after THA? (4) What proportion of patients undergo revision after these THAs? METHODS: For this systematic review, we searched the MEDLINE (PubMed), Scopus, and CINAHL (EbscoHost) electronic databases. We evaluated studies published in English between 1980 and 2020 that had a minimum of 10 patients (with a minimum of 2 years of follow-up) in whom sequelae of septic arthritis of the hip were treated with single-stage THA. We also evaluated studies reporting clinical outcomes by means of the Harris hip score, along with a radiographic assessment of the prosthesis. Updates of previous studies using the same database, case reports, surgical technique reports, systematic reviews, and expert opinions were excluded. No restrictions were applied regarding study design and loss to follow-up. A total of 430 studies were identified through the initial search, and 11 studies were included after applying the inclusion and exclusion criteria. All but two studies, which included a historical control group, were retrospective case series. A total of 691 patients with a mean age of 45 years were involved. A total of 599 patients underwent cementless THAs, 84 patients underwent hybrid THA (cemented stems), and the remaining eight patients received a cemented THA. A total of 287 additional procedures were performed on the acetabulum, including autografting, allografting, and medial wall osteotomies; in three hips, tantalum augments were used. Three hundred thirty-five additional procedures were performed on the femora, including 223 shortening osteotomies and 112 greater trochanter osteotomies. The mean follow-up duration ranged from 5.5 to 15.2 years (minimum follow-up range 2-13 years). To assess the quality of the studies, we used the Methodological Index for Non-randomized Studies and the Assessment of Quality in Lower-limb Arthroplasty, for which a higher score represents a better study quality. The mean Methodological Index for Non-randomized Studies score for case series was 9 of 16 (range 6-12), and 19 and 18 of 24 for the two comparative studies. The mean reporting quality of the Assessment of Quality in Lower Limb Arthroplasty score was 6 of 8 (range 3-8). RESULTS: Because of loss to follow-up, which was not consistently reported in the source studies, we caution the reader that the estimates provided here likely underestimate the risks of adverse events and overestimate the mean hip scores. The pooled proportion of patients in whom infections developed was 1% (seven of 691 THAs). Considering only studies published in the past 10 years, the proportion was 0.7% (two of 276 THAs). The Harris hip score increased from a mean of 52 ± 6 points before THA to a mean of 88 ± 2 points after THA. The pooled proportion of complications, including sciatic nerve palsy, femoral nerve palsy, intraoperative periprosthetic fracture, deep venous thrombosis, and dislocation, was 11% (76 complications among 691 THAs). The pooled proportion of patients who underwent revision was 8% (53 revisions of any components for any reason among 691 THAs) at a mean follow-up interval of 9.1 ± 3 years. CONCLUSION: In THAs for sequelae of childhood septic arthritis, reinfections were uncommon, whereas generally, infection rates were slightly higher than those reported for conventional primary THAs. However, the duration of follow-up might have been insufficient to identify all patients in whom infections later developed, and the available data were not adequate to precisely detect the minimum quiescent period to avoid reinfections. Moreover, the studies in this systematic review were retrospective, and selection bias, transfer bias, and assessment bias likely influenced our findings. The general effect of these biases is to cause an underestimation of the harms of the intervention. Complications, especially intraoperative fracture and nerve palsy, were common in patients with the most-severe infections. Further data on this topic are needed, ideally from multicenter or registry studies with even longer follow-up durations. LEVEL OF EVIDENCE: Level IV, therapeutic study.

The diagnostic value of routine preliminary biopsy in diagnosing late prosthetic joint infection after hip and knee arthroplasty.

AIMS: Biopsy of the periprosthetic tissue is an important diagnostic tool for prosthetic joint infection (PJI) as it enables the detection of the responsible microorganism with its sensitivity to antibiotics. We aimed to investigate how often the bacteria identified in the tissue analysis differed between samples obtained from preoperative biopsy and intraoperative revision surgery in cases of late PJI; and whether there was a therapeutic consequence. METHODS: A total of 508 patients who required revision surgery of total hip arthroplasty (THA) (n = 231) or total knee arthroplasty (TKA) (n = 277) because of component loosening underwent biopsy before revision surgery. The tissue samples collected at biopsy and during revision surgery were analyzed according to the criteria of the Musculoskeletal Infection Society (MSIS). RESULTS: In total, 178 (113 THA, 65 TKA) were classified as infected. The biopsy procedure had a sensitivity of 93.8%, a specificity of 97.3%, a positive predictive value (PPV) of 94.9%, a negative predictive value (NPV) of 96.7%, and an accuracy of 96.1%. Of the 178 infected patients, 26 showed a difference in the detected bacteria from the biopsy and the revision surgery (14.6%). This difference required a change to antibiotic therapy in only two cases (1.1%). CONCLUSION: Biopsy is a useful tool to diagnose PJI, but there may be a difference in the detected bacteria between the biopsy and revision surgery. However, this did not affect the choice of antibiotic therapy in most cases, rendering the clinical relevance of this phenomenon as low. Cite this article: Bone Joint J 2020;102-B(3):329-335.

Delayed total hip arthroplasty infection with Mycobacterium Tuberculosis complex.

Total Hip Arthroplasty (THA) joint infection is an uncommon (0,3-1,7%) (20) but devastating complication after THA. While mostly caused by Gram-positive bacteria, with staphylococci and streptococci accounting for up to 76% of cases (21), orthopaedic surgeons are sometimes faced with atypical germs such as fungi or mycobacteria. We present a case of THA joint infection caused by Mycobacterium tuberculosis (MT) in a patient without a previous history of MT infection. A literature review was performed, and the treatment is discussed.

Candida periprosthetic infection of the hip: a systematic review of surgical treatments and clinical outcomes.

PURPOSE: To produce a systematic analysis of types of treatment and outcomes of Candida hip periprosthetic joint infections and their correlation with specific pathogen species. METHODS: During June 2018, a literature search of candida periprosthetic hip infection in PubMed, Scopus and Embase databases was performed according to the PRISMA (Preferred Reporting Item for Systematic Reviews and Meta-Analyses) guideline. Reviewers used Oxford level of evidence (LoE) and methodological index for non-randomised studies (MINORS) score. Modal distribution of surgical, pharmacological treatment and outcome along with the correlation between types of treatment and outcomes was calculated through the chi-square test. RESULTS: Seventy-nine cases were collected through 35 articles, identifying 81 pathogens. Candida albicans was the most common pathogen. Analysis of LoE reveals 26 LoE 5 (74.29%) and nine LoE 4 (26.71%). From nine  LoE 4, ten patients (20.41%) underwent one-stage revision, 22 patients (44.90%) two-stage revision, 11 patients (22.45%) resection arthroplasty and six patients (12.24%) debridement with prosthesis retention. Global success was obtained in 31 cases (63.27%). Modal distribution revealed a preference for two-stage revision (22/49) and fluconazole as medical therapy (36/49). A significant difference was found between one-stage revision and resection arthroplasty (p = 0.031) or debridement (p = 0.003) and between two-stage revision and debridement (p = 0.013). No differences were found between Candida spp. in terms of the outcomes (p = 0.736). Methodological index showed a poor MINOR score. CONCLUSIONS: Analysis of the literature suggests better clinical outcome with one- or two-stage revision than with resection arthroplasty or debridement, but the level of evidence is low.

Periprosthetic joint infection in aseptic total hip arthroplasty revision.

PURPOSE: There is no consensus regarding systematic screening for infection in aseptic revision total hip arthroplasty (THA). The rationale for systematic intra-operative samples is to increase the sensitivity of latent infections detection, which may require specific treatment. However, the incidence of occult infection in revision THAs is not precisely known. As such, the aim of the study was to evaluate the incidence of occult infection in presumed aseptic revision THAs and identify associated risk factors. METHOD: Bacteriological samples from 523 aseptic THA revisions performed for five years were analyzed. Revisions performed for periprosthetic joint infection (PJI) or clinical suspicion of PJI were excluded. Microbiological cultures were performed using tissue samples in 505 cases (97%), synovial fluid in blood culture vials in 158 (30%), and in dry tubes in 263 (50%). Implants were sent for sonication in 12 cases (2.6%). The mean number of microbiological samples per patient was 3.6 (range, 1-15). Histology samples were collected for 300 patients (57%). RESULTS: The incidence of occult infection was 7% (36 cases) and contamination 8% (42 cases). Among occult infections, the primary reasons for revision were dislocation (42%), aseptic loosening (25%), fracture (19%), and others (14%). The infection rate in the dislocation group was significantly higher than that of other reasons for revision (p < 0.001). Among the patients determined with PJI, the revision THA was performed less than a year after primary in 19 (53%). CONCLUSION: The incidence of occult PJI justifies systematic intraoperative sampling. A short time between primary arthroplasty and revision or an early postoperative dislocation is a factor to suspect infections.

Acometimento pulmonar e articular secundário à síndrome de Lemierre: relato de caso e revisão de literatura / Pulmonary and joint involvement secondary to Lemierre syndrome: case report and literature review

A síndrome de Lemierre caracteriza-se por uma rara entidade que gera tromboflebite da veia jugular interna e embolismo séptico em história da infecção recente da orofaringe, além de sinais radiológicos e isolamento de patógenos anaeróbicos, principalmente Fusobacterium necrophorum. Relatamos o caso de uma paciente do sexo feminino, 13 anos de idade, com histórico de carcinoma de nasofaringe associado ao vírus Epstein-Barr (estadiamento T4N2M0), submetida a procedimentos cirúrgicos e quimiorradioterapia. Iniciou com queixa de mialgia intensa, diplopia, lesões infectadas em membros e choque séptico. Por meio de exames de ultrassonografia cervical com Doppler colorido e tomografia computadorizada de pescoço com contraste endovenoso, foram identificados trombos intraluminais na veia jugular interna, além de trombos sépticos pulmonares, por meio da tomografia computadorizada de tórax. Posteriormente, ainda evoluiu com artrite piogênica coxofemoral esquerda. Foi isolada, por hemocultura, a bactéria Klebsiella pneumoniae Carpemenase, e o tratamento se deu pela associação entre vancomicina, amicacina, meropenem, metronidazol e anfotericina B. Conclui-se que, após o diagnóstico de SL e, embora com múltiplas complicações e diagnóstico tardio, a paciente encontra-se bem e assintomática, além do relato comprovar a dificuldade diagnóstica e de seu tratamento

Lemierre's syndrome is a rare condition that leads to thrombophlebitis of the internal jugular vein and septic embolism following recent oropharyngeal infection, being characterized by radiological signs and isolation of anaerobic pathogens, especially Fusobacterium necrophorum. We report the case of a 13-year-old female patient with history of nasopharyngeal carcinoma associated with Epstein-Barr virus (T4N2M0 staging), who underwent surgical procedures and chemoradiotherapy. Her initial complaint was severe myalgia, diplopia, infected limb injuries, and septic shock. Cervical color Doppler ultrasound and computed tomography scan of the neck with intravenous contrast showed intraluminal thrombi in the internal jugular vein, and chest computed tomography showed pulmonary septic thrombi. Subsequently, she progressed with left coxofemoral pyogenic arthritis. The bacterium Klebsiella pneumoniae Carpemenase was isolated in blood culture, and the patient was treated with the association of vancomycin, amikacin, meropenem, metronidazole, and amphotericin B. It is concluded that, despite the multiple complications and late diagnosis, the patient is well and asymptomatic after the diagnosis of Lemierre's syndrome; in addition, the report proves the difficulty of diagnosis and treatme

Different microbiological profiles between hip and knee prosthetic joint infections.

PURPOSE: The study aims to analyze the demographics and microbiological profiles of hip and knee prosthetic joint infection (PJI) and to compare the microbiological differences between hip and knee PJI. METHODS: We performed a retrospective study of all PJI cases between January 2006 and December 2014 at a referral medical center in Taiwan. RESULTS: A total of 294 PJI cases were collected: 159 were identified as hip PJI and 135 as knee PJI. The most common causative pathogen was Staphylococcus aureus (78 cases, 27%), followed by coagulase-negative staphylococci (CoNS, 42 cases, 14%). Methicillin-resistant staphylococci (MRS) accounted for 21% of all PJI cases. Fungus and mycobacterium were only involved in 12 cases (4.1%) of all PJI cases. Polymicrobial pathogens, anaerobes, and enteric gram-negative bacilli (GNB) were more likely to occur in hip joint prostheses than in knee joint prostheses (22 vs. 6 cases, p = 0.006; 11 vs. 0 cases; p = 0.002; 20 vs. 6 cases; p = 0.014, respectively). CONCLUSION: The prevalence of polymicrobial pathogens, anaerobes, and enteric GNB was higher in the prosthetic hip infection than in the prosthetic knee infection. The high prevalence of MRS, including Methicillin-resistant (MR) S. aureus and MR-CoNS in PJI, may warrant the need for empiric antibiotic therapy with broader coverage while pending the culture result of PJI. Although fungal and mycobacterial PJI cases are rare, the incidence of these infections is relatively high in Taiwan. Fungus and mycobacterium should also be taken into consideration whenever a persistent PJI case is encountered.

Clinically Asymptomatic Patients Show a High Bacterial Colonization Rate of Osteosynthetic Implants Around the Knee but Not the Hip.

BACKGROUND: Patients with osteosynthetic implants around the hip and knee show higher infection rates after joint arthroplasty. Our aim was to evaluate the bacterial colonization of any osteosynthetic implants around the hip and knee in patients without clinical signs of infection. METHODS: Consecutive patients with osteosynthetic implant removal because of related soft tissue irritations or before elective total joint arthroplasty of the hip and knee were prospectively included. Patients with signs of infection were excluded. Based on sonication fluid cultures, implants were classified according to microbial growth as negative (no growth), contaminated (nonsignificant growth), or colonized (significant growth). RESULTS: Sonication cultures were positive in 54 of 203 implants (27%), including 8 of 34 (24%) after orthopedic and 46 of 169 (27%) after traumatological surgery. Of 203 sonication cultures, 22 (11%) grew significant bacterial counts. Most common microorganisms were coagulase-negative staphylococci (46%). Implants around the knee showed a significantly higher rate of positive sonication cultures compared with those around the hip (14% vs 2%, P = .017). CONCLUSIONS: We detected high bacterial implant colonization rates regardless of the initial type of surgery. Predominant pathogens were staphylococci, the most common causative agents of periprosthetic joint infections. Positive sonication results do not necessarily lead to postoperative surgical complications and thus do not equal infection. It remains unclear if patients with evidence of bacterial implant colonization show a higher risk of periprosthetic joint infection after adjacent subsequent total joint arthroplasty. Nevertheless, surgeons should be aware of a significantly higher colonization rate of implants around the knee and take this into consideration when total knee arthroplasty is scheduled in patients with osteosynthetic devices.

Serum C-reactive protein relationship in high- versus low-virulence pathogens in the diagnosis of periprosthetic joint infection.

Little is known about the relationship between the virulence of pathogens in periprosthetic joint infection (PJI) and C-reactive protein (CRP) levels. In this context, we assessed the performance of CRP for PJI. We collected the following data from 987 cases of total joint revision due to PJI and 386 cases of aseptic revision: age, gender, comorbidities, values for serum CRP, leukocytes, microbiology for preoperatively taken aspirations and at least 2 intraoperative biopsies, and presence or absence of a draining sinus. The mean CRP value in the PJI group was 50.2 mg l-1 (sd=62.2), while a lower CRP value of 11.6 mg l-1 (sd=25.3) was found in the control group. There were no significant differences for the CRP values between patients with and without draining sinus (P=0.4423). The difference in CRP between high-virulence and low-virulence micro-organisms was significant for both the hip and the knee (P<0.0001). For the hip, the area under the receiver operating characteristic curve (AUC) of CRP as a diagnostic marker for PJI was 0.830 and, for the knee, the AUC was 0.884. The optimal cutoff point for CRP as a diagnostic marker of PJI, calculated using Youden's index, was 8.90 mg l-1 for the hip and 9.99 mg l-1 for the knee. The study results add valuable new information regarding the organism profile that may help with the diagnostic workup and with the research and development of new strategies for diagnosing and treating PJI.

High cure rate of periprosthetic hip joint infection with multidisciplinary team approach using standardized two-stage exchange.

BACKGROUND: Two-stage exchange arthroplasty is still the preferred treatment choice for chronic PJI. However, the results remain unpredictable. We analyzed the treatment success of patients with an infected hip prosthesis, who were treated according to a standardized algorithm with a multidisciplinary team approach and evaluated with a strict definition of failure. METHODS: In this single-center prospective cohort study, all hip PJI episodes from March 2013 to May 2015 were included. Treatment failure was assessed according to the Delphi-based consensus definition. The Kaplan-Meier survival method was used to estimate the probability of infection-free survival. Patients were dichotomized into two groups depending on the number of previous septic revisions, duration of prosthesis-free interval, positive culture with difficult-to-treat microorganisms, microbiology at explantation, and microbiology at reimplantation. RESULTS: Eighty-four patients with hip PJI were the subject of this study. The most common isolated microorganisms were coagulase-negative staphylococci (CNS) followed by Staphylococcus aureus and Propionibacterium. Almost half of the study cohort (46%) had at least one previous septic revision before admission. The Kaplan-Meier estimated infection-free survival after 3 years was 89.3% (95% CI, 80% to 94%) with 30 patients at risk. The mean follow-up was 33.1 months (range, 24-48 months) with successful treatment of PJI. There were no statistical differences in infect eradication rate among the dichotomized groups. CONCLUSIONS: High infect eradication rates were achieved in a challenging cohort using a standardized two-stage exchange supported by a multidisciplinary approach.

Microbiological profile of infections of the hip joint: An Indian perspective.

Background: Knowledge of the local microbiological epidemiology helps in formulating protocols for appropriate treatment of hip infections. The aim of this study was to profile the organisms cultured from infected hips. Methods: The microbiological profile and sensitivity pattern of organisms in eighty infected hips were reviewed. Results: Infection was secondary to arthroplasty in 35, fracture surgery in 34 and primary septic arthritis in 11. Twenty percent of the infections were polymicrobial, whereas the rest were monomicrobial. Fifty-five percent were Gram-positive, of which 45% were Staphylococcus species (36% methicillin-sensitive Staphylococcus aureus, 20% methicillin-resistant S. aureus, and 44% coagulase sensitive Staphylococcal species). All Staphylococcus species were sensitive to vancomycin, but 20% of Enterococcus species were resistant to vancomycin. One-third of the Enterococcus species and 2% of Staphylococcus species were resistant to teicoplanin. Escherichia coli (n = 10) and Pseudomonas sp. (n = 13) were the most common Gram-negative organism. Although 18% of the Gram-negative organisms were carbapenem resistant, all were sensitive to colistin. Conclusion: Staphylococcus sp. was the most common pathogen found in hip infections. However, the high incidence of Gram-negative infection requires that prophylactic antibiotics cover these organisms as well. The high resistance to first-line antibiotics should be taken into consideration while making protocols. The knowledge of the microbial profile is especially important when considering arthroplasty for arthritis secondary to hip infections.

What Is the Role of Repeat Aspiration in the Diagnosis of Periprosthetic Hip Infection?

BACKGROUND: The American Academy of Orthopedic Surgeons clinical practice guideline currently recommends repeat joint aspiration when workup of periprosthetic joint infection (PJI) reveals conflicting data. This guideline is based on a single study of 31 patients published 25 years ago. We sought to determine the correlation between first and second aspirations and factors that may play a role in variability between them. METHODS: Sixty patients with less than 90 days between aspirations and no intervening surgery were identified at our institution and classified by Musculoskeletal Infection Society (MSIS) criteria as infected, not infected, or not able to determine after both aspirations. Culture results from both aspirations were recorded. The rates of change and correlation in clinical diagnosis and culture results between aspirations were determined. RESULTS: Repeat aspiration changed the diagnosis in 26 cases (43.3%, 95% confidence interval 31.6-55.9, kappa coefficient 0.32, P < .001), and the culture results in 25 cases (41.7%, 95% confidence interval 30.1-54.3, kappa coefficient 0.27, P < .01). Among patients initially MSIS negative, the proportion who changed to MSIS positive was greater for those with a history of prior PJI compared to those without (66.7% vs 0%, P < .05), and the first aspiration mean volume was higher for those changed to MSIS positive compared to those that remained MSIS negative (12.0 vs 3.0 mL, P < .01). Among patients initially MSIS positive, the proportion of patients who changed to MSIS negative was greater for those with a history of adverse local tissue reaction (ALTR) to metal debris compared to patients without suspicion of ALTR (100% vs 7.7%, P < .05). CONCLUSION: Repeat aspiration is particularly useful in patients with conflicting clinical data and prior history of PJI, suspicion of ALTR, or with high clinical suspicion of infection.

[Immunohistochemical Detection of Mast and Dendritic Cells in Periprosthetic Tissues of Aseptically Loosened Total Prostheses]. / Imunohistochemický prukaz mastocytu a dendritických bunek v periprotetických tkáních asepticky uvolnených endoprotéz.

PURPOSE OF THE STUDY This study deals with the possibilities and application of immunohistochemical methods to detect mast and dendritic cells in periprosthetic tissues in patients with aseptically loosened total joint replacements of the knee and hip. The purpose of the study was to quantify and characterize the distribution of mast and dendritic cells in the examined samples and to study the statistically significant relations between the aforementioned cell populations and selected parameters characterizing the patients, implants or tissue response. Based on the proved findings, a possible relation between mast and dendritic cells and histomorphological patterns of aseptic loosening and the benefit of the applied immunohistochemical methods was evaluated. MATERIAL AND METHODS Periprosthetic tissues from a total of 31 patients (17 patients after a revision surgery of hip prosthesis, 14 patients after a revision surgery of knee prosthesis) were examined. The collected samples were processed according to the standard protocol for the purposes of histological and immunochemical examination. Antibodies against tryptase and CD117 were used for immunohistochemical detection of mast cells. Dendritic cells were detected by means of S100 and CD1a antibodies. Quantification of both the cell populations was carried out by optical microscopy in 20 high power fields at 400-times magnification. From among the applied methods we picked the more sensitive one for statistical evaluation. It was tryptase in the case of mast cells and S100 in the case of dendritic cells. RESULTS Mast and dendritic cells were mostly distributed dispersively in periprosthetic tissues; however, they also occurred in groups perivasally or near necrotic parts. The examined samples showed the presence of 60 mast cells and 50 dendritic cells on average. The increased density of mast and dendritic cells was associated with polypously formed pseudosynovium and cement fixation of prostheses; this relation was statistically significant. It was impossible to prove the correlation between the quantity of the observed cell populations and the nature and the number of the observed particles because wear particles were present dispersely in all the samples. Another statistically significant relation to the type of material or implant fixation or other examined histomorphological patterns was not proved. A strong density of mast cells with a minimum presence of dendritic cells was observed in the control patient group. DISCUSSION The differences in density of S100 positive dendritic cells between the control and examined group of patients can be caused by the activation of dendritic cells by exogenous or endogenous pathways of immune processes going on after the implantation of endoprosthesis. The statistically significant interrelation of mast cells, polypously formed pseudosynovium and cement wear particles can be explained at least in part as a tissue reaction induced by cement particles. CONCLUSIONS We proved the presence of two immunologically significant cell populations in periprosthetic tissues. The said findings indicate a conclusion of significant functional participation of mast and dendritic cells in pathogenesis of aseptic loosening and periprosthetic osteolysis. Nevertheless, this will have to be proved in another way and with the use of another method. Key words:dendritic cells, mast cells, aseptic loosening, total joint replacement, immune reaction, adverse reaction.

Septic arthritis of native hip joint by Staphylococcus lugdunensis: a case report

Abstract Staphylococcus lugdunensis is a rare virulent coagulase-negative staphylococcus (CoNS) that behaves similarly to Staphylococcus aureus in causing deep abscesses, skin and soft tissue infections, and central nervous system infections. Additionally, there can be certain blood stream infections including sepsis, septic shock, toxic shock syndrome, and endocarditis complicated by embolic events. Reports of septic arthritis of a native joint associated with this organism have been infrequent, justifying the presentation and discussion of this case.

Total hip arthroplasty following illicit drug abuse.

BACKGROUND: The role of illicit drug abuse in total joint arthroplasty is largely unknown and is likely underestimated. Patients with drug addictions often suffer from septic osteoarthritis or a necrosis of the femoral head. Purpose of the study was to evaluate the operative management and clinical outcome of total hip replacement in patients with a history of intravenous drug abuse. METHODS: This retrospective study included 15 patients with a history of intravenous drug abuse who underwent total hip arthroplasty. A total of 6 females and 9 males with an average age of 34.3 years were identified. Ten patients presented an acute bacterial coxitis (Coxitis-group) and five an aseptic osteonecrosis of the femoral head (Osteonecrosis-group). RESULTS: Ten patients with a bacterial coxitis underwent a two-staged total hip arthroplasty (THA), with temporary insertion of a drug-eluting spacer. Five patients with a necrosis of the femoral head were primarily treated with THA. All patients developed multiple re-infections after insertion of a drug-eluting spacer or THA. Only two patients finally achieved a THA without infection in the period of 3.9 years follow-up. The other 13 patients underwent a Girdlestone arthroplasty (7 patients) or total joint replacement with a chronic fistula (6 patients). CONCLUSION: THA in patients with illicit drug abuse shows a low success rate. Following septic osteoarthritis or osteonecrosis in drug-addicted patients, we recommend a two-stage procedure with temporary insertion of a drug-eluting spacer. THA might follow only under strict premises.