Preoperative dental screening can reduce periprosthetic infections of hip and knee endoprostheses in the first month after surgery: results of a cohort study.

PURPOSE: The oral cavity and, in particular, potential oral foci might pose a risk of periprosthetic joint infection (PJI). The aim of this cohort study was to determine whether practical preoperative dental screening would reduce the prevalence of early PJI in the first month after surgery. METHODS: Patients attending a specialized endoprosthesis implantation clinic between 2018 and 2022 were recruited. Two groups were examined. The test group consisted of patients attending the clinic between 2020 and 2022 and who were referred to their family dentist using a standardized form. The comparison group consisted of patients who were treated in the clinic between 2018 and 2020. They were not referred to their family dentist. The two groups were compared for the prevalence of PJI. Univariate analysis followed by multiple logistic regression was performed to confirm risk factors for PJI in this cohort. RESULTS: 2560 individuals (test group: 1227, comparison group: 1333) were included. The prevalence of PJI was significantly lower in the test group (0.8% vs. 1.8%, p = 0.04). Multiple logistic regression with PJI as the dependent variable showed that a dental referral was a strong predictor of a lower prevalence of PJI (OR: 0.43, CI95 0.205-0.917, p = 0.03). Male gender was also strongly associated with a higher frequency of PJI (OR: 2.68, CI95 1.32-5.42, p = 0.01). Age (OR: 1.06, CI95 1.01-1.10, p = 0.01) and BMI (OR: 1.11, CI95 1.05-1.17, p < 0.01) had little effect on the risk of PJI. CONCLUSION: Dental referral using a standardized form can reduce the prevalence of early PJI. Accordingly, orthopedists and dentists should collaborate in this practical way.

Validation of the Incidence of Reported Periprosthetic Joint Infections in Total Hip and Knee Arthroplasty in the Dutch Arthroplasty Register.

BACKGROUND: Arthroplasty registers underreport the incidence of periprosthetic joint infections (PJIs). We validated the incidence of reported PJIs in total hip arthroplasties (THAs) and total knee arthroplasties (TKAs) in the Dutch Arthroplasty Register (LROI) using data from the Dutch National Nosocomial Surveillance Network (PREZIES). METHODS: All primary THAs and TKAs from the LROI and all primary THAs and TKAs performed in consenting hospitals from PREZIES between 2012 and 2018 were matched on date of birth, date of surgery, sex, hospital, and type of procedure (THA n = 91,208; TKA n = 80,304). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for PJIs registered in the LROI, using PREZIES as a reference. RESULTS: The incidence of registered PJIs in THAs was 1.2% in PREZIES and 0.5% in the LROI. For TKAs, this was 0.7 and 0.4%, respectively. The PJIs in THAs in the LROI had a sensitivity of 0.32 (confidence interval [CI]: 0.29 to 0.35), specificity of 1.00 (CI: 1.00 to 1.00), PPV of 0.74 (CI: 0.70 to 0.78), and NPV of 0.99 (CI: 0.99 to 0.99). In TKAs, the sensitivity, specificity, PPV, and NPV were 0.38 (CI: 0.34 to 0.42), 1.00 (CI: 1.00 to 1.00), 0.65 (CI: 0.59 to 0.70), and 1.00 (CI: 1.00 to 1.00), respectively. CONCLUSIONS: The LROI captures approximately one-third of the PJIs as revision within one year for infection or resection arthroplasty. The capture rate of PJIs can be improved by including all reoperations without component exchange and nonsurgical treatments with antibiotics only.

Semaglutide Use Prior to Total Hip Arthroplasty Results in Fewer Postoperative Prosthetic Joint Infections and Readmissions.

BACKGROUND: Semaglutide, a novel diabetes management medication, is known for its efficacy in inducing weight loss. Despite this, its impact on outcomes after total hip arthroplasty (THA) remains unclear. The aim of this study was to evaluate if THA patients on semaglutide demonstrate: (1) fewer medical complications; (2) fewer implant-related complications; (3) fewer readmissions; and (4) lower costs. METHODS: Using a national claims database from 2010 to 2021, we retrospectively examined diabetic patients prescribed semaglutide who underwent primary THA. This yielded 9,465 patients (Semaglutide = 1,653; Control = 7,812). Multivariable logistic regression was used to evaluate the following outcomes: 90-day postoperative medical complications, 2-year implant-related complications, 90-day readmissions, in-hospital lengths of stay, and day-of-surgery and 90-day episode of care costs. RESULTS: Semaglutide users exhibited lower 90-day readmission rates (6.2 versus 8.8%; odds ratio 0.68; P < .01) and reduced prosthetic joint infections (1.6 versus 2.9%; odds ratio 0.56; P < .01). However, medical complication rates, hospital stays, same-day surgical costs, and 90-day episode costs showed no significant differences. CONCLUSIONS: This study highlights semaglutide users undergoing THA with fewer 90-day readmissions and 2-year prosthetic joint infections. Although no variance appeared in medical complications, hospital stays, or costs, the medication's notable glycemic control and weight loss benefits could prompt pre-surgery consideration. Further research is essential for a comprehensive understanding of semaglutide's impact on post-THA outcomes.

Organism profile and C-reactive protein (CRP) response are different in periprosthetic joint infection in patients with hepatitis.

PURPOSE: Hepatitis B and C are important and relatively common health issues. It is known that many patients who underwent total knee and hip arthroplasty were also diagnosed with hepatitis. These patients are at higher risk of periprosthetic joint infection (PJI). This study aimed to investigate the differences in PJI cases in hepatitis B and C patients. METHODS: This is a retrospective case-controlled single-center study. A total of 270 patients with hepatitis and non-hepatitis (control group) who underwent one-stage septic exchange to the hip and knee joints were included in the study. All patients' previous surgical histories, infective organisms, C-reactive protein (CRP) values before septic exchange, and demographic data were evaluated. All microbiological and laboratory evaluations were performed separately for knee and hip arthroplasty. RESULTS: The mean CRP levels of Hep B- and C-positive patients, who underwent one-stage septic exchange in the knee joint, were 23.6 mg/L. In the control group, this value was 43.1 mg/L and a statistically significant difference was found between the groups (p = 0.004). Gram-negative organisms were identified in a larger proportion of patients with hepatitis who developed PJI in both hip and knee joints and underwent one-stage septic exchange (p = 0.041/p = 0.044). CONCLUSION: PJIs caused by Gram-negative bacteria are encountered more frequently in patients with hepatitis than in the control group. In addition, the CRP rise is less in patients with hepatitis compared to PJI cases in the control group. Patient-specific evaluation is required in cases of PJI in patient groups with co-existing hepatitis.

Evaluation of time to reimplantation as a risk factor in two-stage revision with static spacers for periprosthetic knee joint infection.

INTRODUCTION: We investigated the time to reimplantation (TTR) during two-stage revision using static spacers with regard to treatment success and function in patients with chronic periprosthetic joint infection (PJI) of the knee. METHODS: 163 patients (median age 72 years, 72 women) who underwent two-stage exchange for chronic knee PJI between 2012 and 2020 were retrospectively analyzed (based on the 2011 Musculoskeletal Infection Society criteria). A cutoff TTR for increased risk of reinfection was identified using the maximally selected log-rank statistic. Infection control, aseptic revisions and overall survival were analyzed using Kaplan-Meier survival estimates. Adjustment for confounding factors-the Charlson Comorbidity Index (CCI) and C-reactive protein (CRP)-was done with a Cox proportional hazards model. RESULTS: When TTR exceeded 94 days, the adjusted hazard of reinfection was increased 2.8-fold (95% CI 1.4-5.7; p = 0.0036). The reinfection-free rate was 67% (95% CI 52-79%) after 2 years and 33% (95% CI 11-57%) after 5 years for a longer TTR compared to 89% (95% CI 81-94%) and 80% (95% CI 69-87%) at 2 and 5 years, respectively, for a shorter TTR. Adjusted overall survival and number of aseptic revisions did not differ between the longer TTR and shorter TTR groups. Maximum knee flexion was 90° (IQR 84-100) for a longer TTR and 95° (IQR 90-100) for a shorter TTR (p = 0.0431), with no difference between the groups in Oxford Knee Score. Baseline characteristics were similar (body mass index, age, previous surgeries, microorganisms) for the two groups, except that there was a higher CCI (median 4 vs. 3) and higher CRP (median 3.7 vs 2.6 mg/dl) in the longer TTR group. CONCLUSION: A long TTR is sometimes unavoidable in clinical practice, but surgeons should be aware of a potentially higher risk of reinfection. LEVEL OF EVIDENCE: III, retrospective comparative study.

Clinical outcomes of proximal femoral reconstruction technique combined with THA in the treatment of high dislocation secondary to septic arthritis: a retrospective single-center study.

PURPOSE: The aim of this retrospective study was to examine the clinical outcomes and complications of proximal femur reconstruction (PFR) combined with total hip arthroplasty (THA) in patients with high hip dislocation secondary to septic arthritis (SA). METHODS: Between September 2016 to September 2021, we performed a series of 15 consecutive PFR combined with THA on patients with high dislocation of the hip secondary to SA, of these,12 hips were reviewed retrospectively, with a mean follow-up of 2.5 years (range, 1.5-6 years). The mean age of the patients at the time of surgery was 52 years (range, 40-70 years). RESULTS: All patients were followed up. At 1-year postoperative follow-up, the median HHS increased from 32.50 preoperatively to 79.50 postoperatively. The median VAS decreased from 7 before surgery to 2 at 1 year after surgery. The median LLD reduced from 45 mm preoperatively to 8 mm at 1 year after surgery. The mean operative time 125 ± 15 min (range 103-195 min). Mean estimated blood loss was500 ± 105ml (range 450-870 ml). Mean hospital days 9.5 days (range 6-15 days). Two patients developed nerve injuries that improved after nutritional nerve treatment. One patient had recurrent postoperative dislocation and underwent reoperation, with no recurrence dislocation during the follow-up. There were no cases of prosthesis loosening during the follow-up period. One patient developed acute postoperative periprosthetic joint infection (PJI) that was treated with Debridement, Antibiotics and Implant Retention (DAIR) plus anti-infective therapy, with no recurrence during 2 years of follow-up. CONCLUSION: This study indicates PFR combined with THA shows promise as a technique to manage high hip dislocation secondary to SA, improving early outcomes related to pain, function, and limb length discrepancy.

Evaluating the Child With a Limp.

A limp is a deviation from normal gait pattern, with pain as the presenting feature in about 80% of cases. The differential diagnosis is broad and includes congenital/developmental, infectious, inflammatory, traumatic (including nonaccidental), and, less commonly, neoplastic etiologies. Transient synovitis of the hip is the cause of a limp in the absence of trauma in 80% to 85% of children. It can be differentiated from septic arthritis of the hip by the absence of fever or ill-appearance and with laboratory testing that shows normal or only mildly elevated inflammatory markers and white blood cell count. If septic arthritis is suspected, joint aspiration should be performed urgently with ultrasound guidance and the aspirated fluid sent for Gram staining, culture, and cell count. Patient history, such as breech presentation at birth, and a leg-length discrepancy on physical examination may suggest developmental dysplasia of the hip. Pain reported primarily at night can occur with neoplasms. Hip pain in an adolescent who is overweight or has obesity may suggest slipped capital femoral epiphysis. Knee pain in an active adolescent may suggest Osgood-Schlatter disease. Radiography shows the degenerative femoral head changes in Legg-Calvé-Perthes disease. Abnormalities in bone marrow shown on magnetic resonance imaging indicate septic arthritis. A complete blood count with differential, erythrocyte sedimentation rate, and C-reactive protein should be obtained if infection or malignancy is suspected.

Descriptive Epidemiology of Upper Extremity Septic Arthritis in Children-Review of a Retrospective Multicenter Database.

BACKGROUND: There is limited information on the presentation and management of upper extremity septic arthritis (UESA) in children. Our purpose was to report on the characteristics and short-term treatment outcomes of pediatric UESA from a multicenter database. METHODS: Patients with UESA were identified from a multicenter retrospective musculoskeletal infection database. Demographics, laboratory tests, culture results, number of surgeries, and complications were collected. RESULTS: Of 684 patients with septic arthritis (SA), 68 (10%) patients had UESA. Septic arthritis was most common in the elbow (53%), followed by the shoulder (41%) and wrist (4%). The median age at admission was 1.7 years [interquartile range(IQR, 0.8-8.0 y)] and 66% of the cohort was male. Blood cultures were collected in 65 (96%) patients with 23 (34%) positive results. Joint aspirate and/or tissue cultures were obtained in 66 (97%) patients with 49 (72%) positive results. Methicillin-sensitive Staphylococcus aureus (MSSA) was the most common causative organism overall, but Streptococcus was the most common pathogen in the shoulder. Sixty-six (97%) patients underwent irrigation and debridement, with 5 (7%) patients requiring 2 surgeries and 1 patient (1%) requiring 3 surgeries. The median length of stay was 4.9 days (IQR, 4.0-6.3 d). Thirty-one (46%) children had adjacent musculoskeletal infections and/or persistent bacteremia. No patients experienced venous thromboembolism, and 4 patients with associated osteomyelitis experienced a musculoskeletal complication (3 avascular necrosis, 1 pathologic fracture). One child had re-admission and 3 children with associated osteomyelitis had a recurrence of UESA. Comparison between elbow and shoulder locations showed that children with septic arthritis of the shoulder were younger (4.6 vs. 1.0 y, P =0.001), and there was a difference in minimum platelet count (280 vs. 358 ×10 9 cells/L, P =0.02). CONCLUSIONS: UESA comprises 10% of cases of septic arthritis in children. The elbow is the most common location. Shoulder septic arthritis affects younger children. MSSA is the most common causative organism in UESA, but Streptococcus is common in shoulder septic arthritis. Irrigation and debridement result in excellent short-term outcomes with a low complication rate. Re-admissions and repeat surgical interventions are rare. LEVEL OF EVIDENCE: Level IV, prognostic.

Less Than 1-Year Quiescent Period After Septic Arthritis of the Hip is Associated With High Risk of Periprosthetic Joint Infection Following Total Hip Arthroplasty.

BACKGROUND: Approximately 20,000 patients are diagnosed with septic arthritis annually, with 15% specifically affecting the hip joint. These cases exacerbate arthritic changes, often warranting a total hip arthroplasty (THA). Given their prior history of infection, these patients are predisposed to subsequent periprosthetic joint infections (PJIs). Multiple studies suggest delaying THA after a native septic hip, but no study utilizing a large cohort examined the specific timing to mitigate post-THA PJI risk within a short (<1 year) quiescent period after septic arthritis. We sought to compare patients who were diagnosed with septic hip arthritis at time intervals (0-6, or 6-12 months) prior to an ipsilateral primary THA to a cohort of THA patients who never had a septic hip history. Specifically, we assessed: from 90 days to 2 years (1) revisions due to PJI and (2) associated risk factors for PJI at 2-years. METHODS: A national, all-payer database was queried to identify all patients who underwent a primary THA between 2010 and 2021 and patients who had prior ipsilateral septic hip arthritis were characterized using International Classification of Disease and Current Practice Terminology codes (n = 1,052). A randomized sample of patients who never had a history of septic arthritis prior to undergoing THA was used as a nonseptic group comparison (n = 5,000). The incidences of PJI at 90 days through two years were then identified and compared using bivariate chi-square analyses. Risk factors for post-THA PJIs were then analyzed using multivariate regression models. RESULTS: The septic arthritis cohorts were more likely to require revisions due to PJIs, as compared to the non-septic group at 90 days, 1 year, and 2 years (all P < .0001). Patients who were diagnosed with septic arthritis between 0 and 6 months prior to THA were at greater PJI risk at both one-year (odds ratio (OR) of 43.1 versus 29.6, P < .0001) and two years (OR of 38.3 versus 22.1, P < .0001) compared to patients who had diagnoses between 6 and 12 months. Diabetes mellitus, obesity, and tobacco use were associated risk factors for PJIs at 2 years in the septic hip cohort in comparison to the cohort without a septic hip history. CONCLUSION: Less than a 1-year quiescent period after septic arthritis is associated with a 38 times increased risk and a 22 times risk for post-THA PJI, at 0 and 6 months and 6 and 12 months, respectively. Though patients who undergo THA greater than 6 months after their septic arthritis treatment have a decreased risk compared to those between 0 and 6 months the risks are still high. Orthopaedic surgeons should be aware of the increased risks of PJIs when considering performing a THA in patients with a history of septic arthritis.

Body Mass Index and Revision Total Knee Arthroplasty: Does Cause for Revision Vary by Underweight or Obese Status?

BACKGROUND: Body mass index (BMI) impacts risk for revision total knee arthroplasty (rTKA), but the relationship between BMI and cause for revision remains unclear. We hypothesized that patients in different BMI classes would have disparate risk for causes of rTKA. METHODS: There were 171,856 patients who underwent rTKA from 2006 to 2020 from a national database. Patients were classified as underweight (BMI < 19), normal-weight, overweight/obese (BMI 25 to 39.9), or morbidly obese (BMI > 40). Multivariable logistic regressions adjusted for age, sex, race/ethnicity, socioeconomic status, payer status, hospital geographic setting, and comorbidities were used to examine the effect of BMI on risk for different rTKA causes. RESULTS: Compared to normal-weight controls, underweight patients were 62% less likely to undergo revision due to aseptic loosening, 40% less likely due to mechanical complications, 187% more likely due to periprosthetic fracture, 135% more likely due to periprosthetic joint infection (PJI). Overweight/obese patients were 25% more likely to undergo revision due to aseptic loosening, 9% more likely due to mechanical complications, 17% less likely due to periprosthetic fracture, and 24% less likely due to PJI. Morbidly obese patients were 20% more likely to undergo revision due to aseptic loosening, 5% more likely due to mechanical complications, and 6% less likely due to PJI. CONCLUSION: Mechanical reasons were more likely to be the cause of rTKA in overweight/obese and morbidly obese patients, compared to underweight patients, for whom revision was more likely to be infection or fracture related. Increased awareness of these differences may promote patient-specific management to reduce complications. LEVEL OF EVIDENCE: III.

Povidone-iodine irrigation reduces infection after total hip and knee arthroplasty.

INTRODUCTION: One of the most important challenges faced by orthopedic surgeons is periprosthetic joint infection (PJI). PJI is a common cause for total joint arthroplasty failure with an incidence of 0.3-1.9%. PJI can be devastating for the patient and extremely costly for the healthcare system. There is concern that a major cause of PJI is intra-operative colonization and recent studies have shown a decrease in PJI with the use of dilute povidone-iodine (Betadine®, Avrio Health L.P, Stamford, CT) irrigation prior to wound closure. This study presents our experience with the use of dilute Betadine® irrigation prior to wound closure and its effect on our post-operative hip and knee arthroplasty acute infection rate. MATERIALS AND METHODS: Retrospective chart review performed at our hospital looking at PJI amongst patients who underwent primary total hip arthroplasty (THA) or total knee arthroplasty (TKA) between 2013 and 2017 comparing different irrigation methods (n = 3232). The study group (n = 1207) underwent irrigation prior to wound closure with dilute Betadine for 3 min and the control group (n = 1511) underwent irrigation using normal saline (NS). RESULTS: Using a logistic regression model where the following variables were adjusted for; ASA, age, sex, foley insertion, surgical duration and diabetes mellitus status a statistical significant reduction was seen in any infection (OR 0.45 [0.22; 0.89], p value < 0.05) and SSI (OR 0.30 [0.13; 0.70], p value 0.01) with the Betadine group. No significant reduction was seen with deep infections with the Betadine group compared to the NS group. CONCLUSION: PJI is a devastating complication following total joint arthroplasty and we found Betadine compared to NS irrigation provides an inexpensive and simple method to lower any PJI and more specifically SSI in THA and TKA. LEVEL OF EVIDENCE: III.

Relevant factors in the diagnosis of concomitant osteomyelitis in pediatric hip septic arthritis. A series of 41 cases treated by hip arthroscopy.

INTRODUCTION: Septic arthritis of the hip can appear isolated or concomitant with pelvic osteomyelitis. Delay in the diagnosis of a concomitant osteomyelitis increases the number of required surgeries and of possible complications. PURPOSE: This study aims to establish relevant factors in the diagnosis of concomitant osteomyelitis in cases with septic arthritis of the hip among paediatric patients. METHODS: The data were collected between 2005 and 2020. 41 pediatric patients with suspicion of septic arthritis of the hip joint, treated arthroscopically, were included. The following diagnostic test parameters were collected: ultrasound, MRI, X-Rays, blood samples, temperature, and incapacity to bear weight. The data were analysed with the sensitive analysis method using descriptive statistic. RESULTS: 41 patients were analyzed, with an average age of 6.04 y (7 months to 14 years), of which ten patients (24.39%) presented concomitant osteomyelitis. 6 out of ten patients needed secondary surgery. Regarding age, concomitant osteomyelitis was most common in the age group 4-14 years old. Average number of days of clinical symptoms before admission was 6.2 days. 36/41 cases showed CRP values higher than 2 mg/dl. 9/10 cases with concomitant osteomyelitis showed a CRP > 2 mg/dl, with an average value of 8.9 mg/dl. 22/41 patients underwent an MRI, of which nine cases presented a concomitant osteomyelitis. The probability of a child to have septic arthritis of the hip with adjacent osteomyelitis was analysed through a score based on four factors: impossibility to bear weight and/or hip pain in children in the non-walking age category, CRP > 2 mg/dl, age older than > 4 y, symptoms longer than 4 days. CONCLUSIONS: Children at the age of walking, with incapacity to bear weight, presenting symptoms longer than 4 days and a CRP > 2 mg/dl, should receive an MRI before surgery to exclude adjacent osteomyelitis. LEVEL OF EVIDENCE: IV.

Postoperative IL-6 levels cannot predict early onset periprosthetic hip/knee infections: an analysis of 7,661 patients at a single institution.

Prior studies have outlined C-reactive protein (CRP) within the first 5 d following total hip arthroplasty (THA) as an inappropriate indicator of an early periprosthetic joint infection (PJI). Recently, interleukin-6 (IL-6), as a potential inflammatory marker following total joint arthroplasty (TJA), has gained increasing interest, particularly due to its considerably shorter half-life. The aim of the present study was to assess IL-6 measured on postoperative day 3 following TJA as a prediction marker of early onset PJI. 7,661 patients, who underwent total hip or knee arthroplasty (THA, TKA) at a single institution between 2016 and 2019, were evaluated. Serum IL-6 values were measured on postoperative day 3 and compared between patients, with and without early onset PJI in the postoperative follow-up, matched for age, gender, Surgical Site Infection Risk Score and Charlson comorbidity index. Overall (n = 7,661), there was no statistically significant difference in serum IL-6 levels comparing patients with and without early onset PJI following THA [38.9 pg/ mL vs. 32.0 pg/mL, p = 0.116] and TKA [30.6 pg/mL vs. 28.2 pg/mL, p = 0.718]. Male gender and high body mass index were associated with an increased risk of early onset PJI following THA (p = 0.027, p = 0.002). Matched cohort analysis (n = 86) showed no statistically significant difference in serum IL-6 levels between patients with and without early onset PJI following THA (p = 0.680) and TKA (p = 0.910). Serum IL-6 values on postoperative day 3 following THA or TKA could not predict early onset PJIs.

Early diagnosis and treatment of acute brucellosis knee arthritis complicated by acute osteomyelitis: two cases report.

BACKGROUND: Brucellosis is an endemic systemic infectious disease, the most common complication is bone and joint involvement. Sacroiliac joint and spinal joint are the most frequently involved sites in adults, but knee joint infection is rare, and acute infectious knee arthritis complicated by acute osteomyelitis is even extremely uncommon in adults. Here, we report two cases of acute septic knee arthritis complicated by acute osteomyelitis caused by Brucella melitensis (B. melitensis). CASE PRESENTATION: Both patients had a history of traveling in animal husbandry areas within three months. On clinical examination, their right knee joint was tender, swollen, had limited movement and an effusion was present. Imaging examination showed effusion and synovial thickening of the right knee joint, as well as subchondral bone edema of the distal femur and proximal tibia. Laboratory examination showed that the serum agglutination test (SAT) in both patients were positive (1: 640 and 1: 320) without leukocytosis, although the proportion of lymphocytes, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) significantly increased. Both patients underwent knee joint aspiration. Real-time polymerase chain reaction (Real-time PCR) analysis of synovial fluid showed that there was B. melitensis, and blood bacterial culture was negative. We determined that two patients had acute brucellosis knee arthritis complicated by acute osteomyelitis. Antibiotic treatment was given during hospitalization consisting of doxycycline (0.1 g po bid) and rifampicin (0.6 g po qd) for six weeks, and the changes of inflammatory indexes were closely monitored. At discharge, the symptoms had completely resolved, imaging abnormalities disappeared, and inflammatory indexes returned to normal. There was no recurrence of the disease at 1-year follow-up. CONCLUSION: Acute brucellosis knee arthritis complicated by acute osteomyelitis is a rare but serious complication of brucellosis in adults. There is no obvious specificity of clinical manifestation and imaging examination. Early diagnosis and treatment can prevent the occurrence of knee joint deformity and even pathological fracture. Clinicians should fully consider the possibility of brucellosis where the travel or occupational history is suggestive.

Hyperammonemia in a septic patient with Ureaplasma parvum arthritis: a case report.

BACKGROUND: Septic arthritis requires prompt diagnosis and treatments. Rare pathogens should be considered when patients respond poorly to the initial antibiotic treatments. Ureaplasma parvum is an opportunistic pathogen that commonly resides in the human urogenital tract. Its infection commonly causes hyperammonemia. Hyperammonemia from Ureaplasma parvum septic arthritis has never been reported previously. CASE PRESENTATION: A 65-year-old male presented with fever and left lower leg pain and swelling for more than ten days. Septic arthritis and sepsis were considered after laboratory tests and arthrocentesis. However, he responded poorly to the antibiotic treatments, including cefoperazone-sulbactam, imipenem-cilastatin, and linezolid. His mental status deteriorated rapidly with elevated blood ammonia levels with unremarkable liver function test and sonogram examination results. Despite the treatments with lactulose, L-ornithine L-aspartate, mannitol, and hemodialysis therapy to lower his ammonia level, his blood ammonia level remained persistently high. Finally, metagenomic sequencing of the left knee synovial fluid reported Ureaplasma parvum, which was considered to contribute to his hyperammonemia. CONCLUSION: Ureaplasma parvum could cause septic arthritis with hyperammonemia. Genetic tests, such as polymerase chain reaction and next-generation sequencing techniques, could provide a sensitive and fast diagnosis of Ureaplasma parvum.

Gastrointestinal Endoscopy and the Risk of Prosthetic Joint Infection: A Nationwide Database Analysis.

BACKGROUND: Current guidelines suggest antibiotics prophylaxis is not necessary for patients with orthopedic prosthetics undergoing gastrointestinal endoscopy. Clinical evidence to support this recommendation is lacking. AIMS: To analyze the association between inpatient gastrointestinal endoscopy and prosthetic joint infection (PJI) in patients with a recent arthroplasty. METHODS: We included patients admitted from July to October of each calendar year (index admissions) who had an arthroplasty in the same calendar year prior to the index admission. We followed the occurrence of PJI for 60 days after the index admission. Only admissions from July to October were chosen as index admissions, and the follow-up period was limited to 60 days because the database structure prohibits the analysis of events in different calendar years. We compared the rate of 60-day PJI between those who had gastrointestinal endoscopy on index admissions to those who had not. We excluded patients aged less than 18 years, who died on index admission, or had any infection in the same calendar year before or during the index admission. RESULTS: Of 1,831,218 patients with arthroplasty, 88,345 met the inclusion criteria, out of which 5,855 had gastrointestinal endoscopy. The rate of 60-day PJI in those who had endoscopy was 0.23%, and in those who had not was 0.52% (P < 0.001). EGD without excision (adjusted odds ratio [95% confidence interval]: 0.20 [0.03-1.42], P = 0.107), EGD with excision (0.58 [0.21-1.60], P = 0.295), colonoscopy without excision (0.43 [0.11-1.72], P = 0.233), colonoscopy with excision (0.31 [0.04-2.21], P = 0.241), and PEG/PEJ (0.38 [0.05-2.71], P = 0.337) were not associated with risk of 60-day PJI. We found no PJI cases in patients underwent esophageal dilation, ERCP, and EUS with FNA. CONCLUSIONS: Gastrointestinal endoscopy in hospitalized patients with a recent previous arthroplasty is not associated with an increased risk of 60-day prosthetic joint infection.

Age and C-reactive protein as modifiers of Kocher criteria in pediatric septic knee monoarthritis.

INTRODUCTION: Although Kocher criteria can distinguish a septic hip from an aseptic cause, they may not apply to a septic knee. We aimed to identify predictors to discriminate septic and aseptic causes of acute knee monoarthritis in children who underwent arthrocentesis. METHODS: We conducted a retrospective cohort study among children who underwent arthrocentesis for suspected septic arthritis of the knee. Collected data included demographic, clinical and laboratory characteristics. We performed univariate and multivariable analyses to identify predictors of the septic knee. We further investigated accuracy of different predictive models. RESULTS: A total of 60 patients who underwent arthrocentesis for suspected knee septic arthritis were included in this study. Septic arthritis of the knee was confirmed in 32 (53%) patients. Age ≤ 5 years (OR 4.237, [95% CI 1.270-14.127], p = 0.019), WBC > 12,000 cells/mm3 (OR 5.059, [95% CI 1.424-17.970], p = 0.012), and CRP > 2 mg/dL (OR 3.180, [0.895-11.298], p = 0.074) were the most important predictors of a septic knee. Three-tier model comprising these three factors (AUC 0.766) and 4-tier model with addition of fever >38.5°C (AUC 0.776) performed better than Kocher criteria (AUC 0.677), modified Kocher criteria (AUC 0.699) and Full Model (adding age ≤ 5 years and CRP >2 mg/dL to Kocher criteria) (AUC 0.746). Full Model successfully ruled out septic arthritis if all 6 criteria were negative. CONCLUSION: Based on these findings, we propose an algorithm to identify low, intermediate and high-risk patients for knee septic arthritis. Our proposed two-step algorithm incorporating major (age, WBC, CRP) and minor (fever, ESR, non-weight bearing) criteria can serve as a simple decision-support tool to justify arthrocentesis in children with suspected knee septic arthritis.

What Is the Impact of Automated Synovial Cell Counting on Different Aseptic Causes and Periprosthetic Conditions Associated With Revision THA?

BACKGROUND: Studies have suggested that automated synovial cell counting may overestimate the white blood cell (WBC) count, resulting in false positive tests when evaluating patients for the possibility of periprosthetic joint infection (PJI) after THA. However, associations between WBC counts high enough to mimic PJI in patients whose arthroplasties are not infected but rather are experiencing a variety of aseptic problems-including but not limited to metallosis, polyethylene wear, and recurrent dislocation-have not, to our knowledge, been adequately addressed. In addition, there is a lack of analyses about the polymorphonuclear percentage (PMN%) when assessed by automated analyzers in this context. QUESTIONS/PURPOSES: In the context of different indications for aseptic revision and different periprosthetic hip pathologic findings, we asked: (1) What were the synovial WBC count levels, and what proportion of values were above the 2018 International Consensus Meeting (ICM) cutoff (3000 cells/µL)? (2) What were the synovial PMN% levels, and what proportion of values were above the 2018 ICM (70%)? METHODS: We retrospectively studied the preoperative cell count analyses of synovial fluid in patients who underwent revision THA for aseptic reasons at our tertiary referral arthroplasty center between January 2015 and December 2017. We considered all revisions performed on patients during that time potentially eligible, and after prespecified exclusions were applied (exclusions mainly included 15% [197 of 1306] sporadic missing data and 12% [155 of 1306] insufficient synovial fluid obtained in the aspirate), a total of 702 patients undergoing revision THA for aseptic reasons remained for the final analysis. As far as we know, no patients underwent re-revision for PJI at a mean follow-up of 46 ± 11 months, which tends to confirm our impression that indeed these hips did not have PJI. Cell count analyses were conducted using an automated analyzer. Clinical findings, preoperative radiographs, and surgical reports--confirmed by available histologic results--were used to establish diagnoses. We evaluated these hips considering the recommendations of the 2018 ICM (WBC count of 3000 cells/µL and PMN% of 70%) to see what proportion of them would have been characterized as likely having PJI on basis of those cutoff values. The mean WBC count for the entire cohort was 2120 ± 2395 cells/µL. The mean PMN% for the entire cohort was 36% ± 22%. RESULTS: Compared with aseptic loosening and recurrent dislocation, polyethylene wear had the highest mean WBC count (3817 ± 3711 cells/µL; p < 0.001). Of the investigated periprosthetic conditions, wear-induced synovitis had the highest value (4464 ± 3620 cells/µL; p < 0.001). Considering the ICM threshold, polyethylene wear showed the highest proportion of WBC counts above 3000 cells/µL among the indications for aseptic revision (60% [25 of 42]; p < 0.001). Of the periprosthetic conditions, wear-induced synovitis showed the highest proportion beyond the ICM cutoff (60% [50 of 83]; p < 0.001). The mean PMN% for aseptic causes ranged between 28% and 44% without differences among them (p = 0.12). Patients with metallosis had the highest mean PMN% of the periprosthetic conditions investigated (45% ± 25%; p = 0.007). Regarding the ICM threshold, metallosis resulted in the largest proportion of patients with a PMN% above 70% (21% [10 of 47]; p = 0.003), and that for wear-induced synovitis was 6% (5 of 83; p = 0.42) and for osteolysis was 3% (1 of 33; p = 0.51). There were no differences among aseptic loosening, recurrent dislocation, and polyethylene wear in terms of the proportion above 70% among the aseptic revision causes. CONCLUSION: Using automated cell counting, we found that WBC counts differ widely across indications for aseptic revision THA, and a high proportion of patients who underwent revision THA for aseptic reasons had WBC counts above the commonly used threshold of 3000 cells/µL. However, the PMN% was much less affected in several common indications for aseptic revision THA, making this measure more reliable for interpreting aspiration results using an automated analyzer. Based on the data distributions we observed, manual counting techniques might be considered in particular among patients with polyethylene wear, metal-on-metal bearing surfaces, or suspected metallosis. However, an elevated WBC count alone, observed using an automated analyzer in the context of polyethylene wear, should not be considered to be strongly suggestive of PJI, since that finding occurred so commonly among patients without infection. LEVEL OF EVIDENCE: Level III, diagnostic study.

For Patients With Acute PJI Treated With Debridement, Antibiotics, and Implant Retention, What Factors Are Associated With Systemic Sepsis and Recurrent or Persistent Infection in Septic Patients?

BACKGROUND: Periprosthetic joint infection (PJI) can lead to a severe systemic inflammatory response and may result in systemic sepsis. However, little is known about how often systemic sepsis may occur in patients with PJI, and whether sepsis is associated with a greater likelihood of persistent or recurrent PJI. QUESTIONS/PURPOSES: (1) Among patients who present with acute or acute hematogenous PJI and who were treated with debridement, antibiotics, and implant retention (DAIR), what proportion have sepsis and what factors are associated with a presentation with sepsis? (2) For patients presenting with sepsis, what factors are associated with persistent or recurrent PJI? METHODS: In all, 320 patients who underwent DAIR for the treatment of acute postoperative or acute hematogenous PJI between January 2000 and December 2019 were included in this study. Exclusion criteria were patients with other known sources of infection, such as pneumonia or urinary tract infections, which could contribute to systemic sepsis (6% [18 of 320]), patients with chronic PJI, and those with less than 6 months of follow-up (21% [66 of 320]). Our final cohort consisted of 236 patients presenting with an acute postoperative or acute hematogenous PJI who underwent an irrigation and debridement procedure. Sepsis was defined by the criteria for systemic inflammatory response syndrome (SIRS) or bacteria-positive blood culture results. Inclusion of patients with positive blood culture by organisms that caused their joint infection was important as all patients presented with fulminant acute infection of a prosthetic joint. Data, including vital signs, surgical variables, and treatment outcomes, were collected retrospectively through a chart review of an electronic medical record system. The statistical analysis comparing patients with sepsis versus patients without sepsis consisted of logistic regression to identify factors associated with sepsis. After confirming its ability to identify patients with a higher association with the development of sepsis through area under the curve models, a nomogram was generated to standardize our results from the regression, which was supported by the area under the curve model, to help readers better identify patients who are more likely to develop sepsis. RESULTS: A total of 44% (103 of 236) of patients had infections that met the criteria for sepsis. After controlling for confounding variables, including congestive heart failure, anemia, serum C-reactive protein (CRP), and the male sex, it was revealed that serum CRP (odds ratio 1.07 [95% confidence interval 1.04 to 1.11]; p < 0.001) and male sex (OR 1.96 [95% CI 1.03 to 3.81]; p = 0.04) were associated with the development of systemic sepsis. For patients presenting with sepsis, persistent or recurrent PJI were associated with an increased CRP level (OR 1.06 [95% CI 1.02 to 1.11]; p = 0.01) and number of prior surgical procedures on the joint (OR 2.30 [95% CI 1.21 to 4.89]; p = 0.02). CONCLUSION: Overall, our findings support that patients with systematic sepsis may benefit from two-stage revision rather than DAIR to decrease the bioburden more effectively, especially in those with methicillin-resistant Staphylococcus aureus and polymicrobial infections. High serum CRP levels and a history of prior surgical procedures on the involved joint should trigger prompt, aggressive surgical treatment if the patient's overall clinical status can tolerate such an intervention. LEVEL OF EVIDENCE: Level III, therapeutic study.

Polyarticular Septic Arthritis Secondary to Septic Thrombophlebitis of the Brachiocephalic Vein: A Rare Case Report.

BACKGROUND: Polyarticular septic arthritis (PASA) accounts for approximately 15% of all septic arthritides and is rare in immunocompetent adults. Even with appropriate therapy PASA's mortality rate is nearly 50%. CASE REPORT: We report a rare presentation of PASA caused by idiopathic septic thrombophlebitis of the brachiocephalic vein in an immunocompetent adult female patient who presented with symptoms of right clavicular, left wrist, and right hip pain associated with fevers. Methicillin-sensitive Staphylococcus aureus was isolated in blood cultures and joint aspiration of one of the affected hips. Transesophageal echocardiogram was negative for valvular vegetations and computed tomography chest with contrast revealed thrombi in the brachiocephalic and subclavian veins extending to the superior vena cava. It also showed bilateral pulmonary nodules consistent with septic pulmonary emboli. No clear precipitant for the underlying septic thrombophlebitis was identified. Management was conservative, with systemic anticoagulation and IV antibiotics. The patient's symptoms improved, and she was discharged to subacute rehabilitation. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Early diagnosis and treatment of PASA in the emergency department is imperative to reducing overall morbidity and mortality associated with this condition. To the best of our knowledge, this is the only case report of idiopathic septic thrombophlebitis of the subclavian vein causing PASA in an immunocompetent adult.