A model of Staphylococcus aureus bacteremia, septic arthritis, and osteomyelitis in chickens

We studied the occurrence, magnitude, and kinetics of bacteremia and the resultant osteomyelitis and septic arthritis in an avian model of Staphylococcus aureus infection. Thirty-day-old male broiler chicks were inoculated i.v. with 10(5), 10(6), or 10(7) cfu of strain Duntravis, a beta-hemolytic, coagulase-producing, capsular type 8 isolate from the synovial fluid of a 2-year-old black boy. Bacteremia occurred in 80%, 90%, and 100% of animals inoculated with 10(5), 10(6), or 10(7) cfu, respectively. The magnitude of bacteremia in surviving, bacteremic animals increased for 96 hours after inoculation and then decreased after a plateau phase. Osteomyelitis and septic arthritis occurred only in chicks that were continuously bacteremic. The occurrence of osteomyelitis was uniform among continuously bacteremic animals and developed 1 to 23 hours after inoculation. Chickens are susceptible to systemic infections with S. aureus. Bacteremia, osteomyelitis, and septic arthritis may be induced in healthy chickens without prior manipulations that depress their resistance.     

Aspirations of the ilium and proximal femur increase the likelihood of culturing an organism in patients with presumed septic arthritis of the hip

Purpose

To test the hypothesis that collecting material for culture from metaphyseal bone of the ilium and proximal femur at the time of a hip aspiration will increase the sensitivity to detect an infectious organism in patients with presumed septic arthritis of the hip.

Methods

We retrospectively reviewed a series of 36 patients with presumed septic arthritis of the hip, based on clinical exam and serum inflammatory markers, who underwent aspirations of hip synovial fluid as well as blood from the ilium and proximal femur. Culture results from aspirates of synovial fluid and bone and tissue from capsule were compared to determine the sensitivities and specificities of a synovial aspirate alone versus synovial aspirate plus aspirates of the ilium and proximal femur to detect infection.

Results

The sensitivity of hip synovial fluid aspirates to detect infection via positive culture was only 63 %, though this increased significantly to 100 % when the results of cultures of aspirates of the ilium and proximal femur were included. The specificities were equivalent in both modalities (≥90 %). We conclude that obtaining aspirates of the ilium and proximal femur at the time of hip synovial fluid aspiration increases the likelihood that the procedure will return an infectious organism.

Conclusion

Positive cultures from a child with a septic hip or peri-articular hip infection help to efficiently and effectively guide antibiotic treatment. The child with a septic hip or peri-articular hip infection and positive cultures is likely to receive more narrow-spectrum therapy, potentially decreasing the overuse of broad-spectrum antibiotics.

Level of evidence: diagnostic study level III

Development of diagnostic criteria on the basis of a series of non-consecutive patients (with universally applied reference “gold standard”).     

儿童急性骨髓炎伴临近化脓性关节炎临床特征分析

目的 通过和不伴有化脓性关节炎的儿童急性骨髓炎对比分析,探讨儿童急性骨髓炎伴临近化脓性关节炎的临床特征。方法 收集2017年11月至2022年5月山东大学附属儿童医院诊治的108例急性骨髓炎患儿的病例资料进行回顾性分析,根据有无化脓性关节炎分为观察组和对照组。骨髓炎伴临近化脓性关节炎的48例患儿为观察组,其中男孩28例,女孩20例,年龄为19天~12岁。无化脓性关节炎的60例骨髓炎患儿为对照组,其中男孩38例,女孩22例,年龄为1个月9天~15岁。所有患儿治疗均采用抗生素联合骨皮质开窗引流,观察组患儿同时行关节引流。对两组患儿性别、年龄、起病时最高体温、发病时间、细菌培养阳性率、炎症指标、手术次数、住院天数、并发症等进行对比分析。结果 观察组和对照组在年龄、性别、细菌培养阳性率上差异无统计学意义（P＞0.05）;观察组和对照组发病时最高体温分别为（39.21±0.84） ℃和（39.01±0.84） ℃,白细胞中位数分别为15.95×10⁹/L和15.79×10⁹/L,中性粒细胞中位数分别为12.08×10⁹/L和10.35×10⁹/L,红细胞沉降率分别为（62.26±25.57） mm/h和（60.49±25.38） mm/h,差异均无统计学意义（P＞0.05）;观察组和对照组C-反应蛋白分别为（94.29±62.11） mg/L和（64.02±45.25） mg/L,发病时间中位数分别为5天和6天,住院天数中位数分别为32.5天和26.0天,手术次数中位数分别为3次和2次,差异均有统计学意义（P＜0.05）;观察组2例出现关节僵硬,2例复发,2例出现髋关节病理性脱位,对照组1例出现关节僵硬,1例出现病理性骨折,差异无统计学意义（P＞0.05）。结论 和不伴有化脓性关节炎的儿童急性骨髓炎相比,骨髓炎伴临近化脓性关节炎的患儿就诊时间较早,C-反应蛋白升高程度更高,治疗需要更多的手术次数,住院时间较长,治疗上采用抗生素联合骨皮质开窗和关节引流,整体预后良好。     

Pediatric Hand Injuries Requiring Closed Reduction at a Tertiary Pediatric Care Center

Background: Hand fractures and dislocations are common injuries in the pediatric population. This study aims to characterize the pediatric hand injuries that required closed reduction and identify those that required multiple reduction attempts. Methods: A retrospective cohort study was carried out in patients younger than 18 years of age with hand fractures or dislocations who underwent closed reduction in the emergency department (ED). Patients who ultimately required surgical reduction and fixation were not included. Results: Of the 310 hand injuries identified, 148 (114 fractures and 34 dislocations) underwent closed reduction in the ED; 7.4% of those required repeat reduction. Hand injuries that most often required repeat reduction included metacarpophalangeal joint dislocations (20.0%) and proximal phalanx neck (16.7%), metacarpal shaft (15.4%), metacarpal neck (6.2%), and proximal phalanx base (5.6%) fractures. No modifiable risk factors predicting the need for repeat reduction were identified. Conclusions: Some pediatric hand injuries are more likely to require repeat closed reduction by a hand surgeon. This retrospective study is the first step toward quality improvement as it provides opportunities for further research into the factors contributing to reductions that are unsuccessful at the first attempt. Identification of these factors and implementation of quality improvement measures are necessary to ensure the effective treatment of all pediatric hand injuries.     

Long-term results of bacterial septic arthritis of the wrist

Septic arthritis of the wrist is a serious condition, yet little is known about its long-term outcome. A retrospective analysis of 22 patients treated for bacterial septic arthritis of the wrist was conducted with subsequent follow-up of 18 patients with a median period of 44 months to assess functional results via DASH-Score and clinical examination.Arthrotomy was used to treat all patients; in 19 patients, multiple operations were needed to cure the infection. Follow-up revealed a mean DASH-score of 34 (SD 22) and a significant correlation with needed surgical radicality and number of needed operations. The range of motion of the wrist and grip strength of the affected side was 49% (SD 20%) and 70% (SD 28%) of the contralateral side, respectively. In conclusion, septic arthritis of the wrist leads to long-term functional restrictions with a strong correlation with the stage of the disease. Hence, early diagnosis and treatment are paramount.     

Natural history of acute septic arthritis in an avian model

An experimental model of acute septic arthritis is described, utilizing the injection of S. aureus into chicken hock joints. The course of the infection was monitored over a 14-day period by measurement of chicken growth rate, histopathology of the joint, number of bacteria, and number and type of leukocytes in the synovial fluid. Bacterial numbers decreased initially then increased rapidly over the first 24 h. Leukocyte counts rose sharply, starting between 60 and 90 min after injection. Gross destruction of articular cartilage was observed at 4 days, and appeared to be initiated by the adherence of the staphylococci to the cartilage surface followed by their penetration and invasion of vascular tunnels in the epiphyseal cartilage. Extensive (but focal) erosion of the articular surface was evident by 14 days.     

Primary septic arthritis of the acromio-clavicular joint: case report and review of literature

Primary septic arthritis of the Acromio clavicular joint is an uncommon disorder and is rarely seen even in an immunocompromised individual. We report a case of primary septic arthritis of the acromio-clavicular (A-C) joint caused by Staphylococcus aureus without any predisposing factors. The patient was admitted with left shoulder pain, restricted movements and fever. Laboratory parameters showed high C-reactive protein, raised erythrocyte sedimentation rate and leucocytosis. Blood cultures were positive for Staphylococcus-aureus. Magnetic resonance imaging (MRI) using Gadolinium enhancement revealed marked effusion in the A-C joint. Aspiration from the A-C joint revealed a heavy growth of Staphylococcus-aureus. The patient was successfully treated with 8 weeks of appropriate antibiotics with complete resolution of infection and return to full function.     

Effect of hyperbaric oxygen exposure on oxygen tension within the medullary canal in the rabbit tibial osteomyelitis model

The effect on intramedullary oxygen tension of 100% oxygen exposure at 1, 2, 2.4, and 3 atm pressure was studied in 12 New Zealand white rabbits with chronic right tibial osteomyelitis. The model, modified from that described by others, incorporates a multipuncture silastic closure plug placed transcortically in the proximal tibial metaphysis through which platinum needle, polarographic electrode oxygen tension determinations can be made without repeat surgical exposure. In 40% of the control, left, noninfected tibial metaphyses the baseline oxygen tension with the animals breathing room air at sea level was suboptimal for leukocyte bacterial killing. This oxygen tension was depressed further in the infected right tibia. Medullary canal oxygen tension increased in response to hyperbaric oxygen exposure in both the infected and noninfected tibiae. Whereas the amount of the oxygen tension increase varied with the presence of infection and depth of dive, neither the time for oxygen tension to plateau nor the time required for return to baseline tension after completion of hyperbaric oxygen exposure varied with the presence of infection or depth of dive. After completion of hyperbaric oxygen exposure, the oxygen tension within the medullary canal returned to baseline within 15 min.     

Septic arthritis of the hand: Current issues of etiology,pathogenesis, diagnosis,treatment

Septic arthritis of the hand is a serious disease that often results in dysfunction of the joint or even the need to perform amputation of the finger. They rank second in the frequency of occurrence after lesions of the knee joint. Many points concerning the etiology, the timing of the development of cartilage destruction and the development of osteomyelitis, approaches to surgical treatment, the duration of antibiotic therapy, and the start of rehabilitation measures remain the subject of numerous discussions. Based on a search in the PubMed, Web of Science and Google Scholar databases down to 1990-2021, publications on septic arthritis of the hand were found and analyzed. The following inclusion criteria were used in our review: (1) Septic arthritis of the hand; (2) Published in a peer review journal; (3) Written in English; and (4) Full text version available. Studies were excluded if they met any of the following criteria: (1) Letters; (2) Articles published in abstract form only; and (3) Cadaveric studies. Septic arthritis of the hand was characterized by the most frequent damage to the joints of the index and middle fingers (> 50% of cases). Up to 90% of cases, the infection enters the joint as a result of penetrating trauma, animal bites, etc. Staphylococcus aureus became the most frequently isolated microorganism (30%-55%), and its polyantibiotic-resistant form Methicillin-resistant Staphylococcus aureus was found, according to various sources, from 0% to 73% among all isolated Staphylococcus aureus. In arthritis, Pasteurella multocida (6%-11%) is often isolated as a result of animal bites. Articular cartilage destruction in the experiment developed within 24-48 h after infection. In clinical studies, the development of osteomyelitis was noted when treatment was delayed by more than 10 d. X-ray data during the first two weeks were uninformative. Priority of surgical treatment of septic arthritis. Drainage and surgical treatment, and with the development of osteomyelitis, the implementation of arthrodesis. Antibacterial therapy for 2-4 wk and early start of rehabilitation measures. Timely surgical treatment in combination with antibiotic therapy and rehabilitation makes it possible to obtain a positive result in the treatment of septic arthritis of the hand.     

外科脓毒血症病人血磷水平变化的初步研究

目的:研究外科危重病人在全身炎症反应综合征(SIRS)、脓毒血症和脓毒性休克阶段血磷水平变化的趋势。方法:回顾性研究2003年1月到2003年4月在瑞金医院外科ICU连续入住病人的血磷值,比较不同病程阶段(非重症、SIRS、脓毒血症和脓毒性休克)病人的血磷水平。结果:在外科ICU非重症病人中,血磷水平都正常;而在SIRS阶段病人,部分标本的血磷水平降低(占标本数30.4%),但平均值仍属正常。脓毒血症阶段病人的血磷水平则明显降低,平均为(0.66±0.17)mmol/L,显示低磷血症的标本数占90.9%;脓毒性休克时病人的血磷降低更为明显,平均为(0.48±0.22)mmol/L。方差分析显示各组间两两比较都有显著差异。结论:外科危重病人中,随着疾病从SIRS加重到脓毒性休克,其血磷降低程度亦逐渐加重。     

Preoperative Intranasal Mupirocin Ointment Significantly Reduces Postoperative Infection with Staphylococcus aureus in Patients Undergoing Upper Gastrointestinal Surgery

(Received for publication on Nov. 24, 1998; accepted on July 13, 1999)     

Prevention of Surgical Site Infection in Total Joint Arthroplasty: An International Tertiary Care Center Survey

Background

Prevention strategies are critical to reduce infection rates in total joint arthroplasty (TJA), but evidence-based consensus guidelines on prevention of surgical site infection (SSI) remain heterogeneous and do not necessarily represent this particular patient population.

Questions/Purposes

What infection prevention measures are recommended by consensus evidence-based guidelines for prevention of periprosthetic joint infection? How do these recommendations compare to expert consensus on infection prevention strategies from orthopedic surgeons from the largest international tertiary referral centers for TJA?

Patients and Methods

A review of consensus guidelines was undertaken as described by Merollini et al. Four clinical guidelines met inclusion criteria: Centers for Disease Control and Prevention''s, British Orthopedic Association, National Institute of Clinical Excellence''s, and National Health and Medical Research Council''s (NHMRC). Twenty-eight recommendations from these guidelines were used to create an evidence-based survey of infection prevention strategies that was administered to 28 orthopedic surgeons from members of the International Society of Orthopedic Centers. The results between existing consensus guidelines and expert opinion were then compared.

Results

Recommended strategies in the guidelines such as prophylactic antibiotics, preoperative skin preparation of patients and staff, and sterile surgical attire were considered critically or significantly important by the surveyed surgeons. Additional strategies such as ultraclean air/laminar flow, antibiotic cement, wound irrigation, and preoperative blood glucose control were also considered highly important by surveyed surgeons, but were not recommended or not uniformly addressed in existing guidelines on SSI prevention.

Conclusion

Current evidence-based guidelines are incomplete and evidence should be updated specifically to address patient needs undergoing TJA.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-013-9369-1) contains supplementary material, which is available to authorized users.     

Addition of bisphosphonate to antibiotic and anti-inflammatory treatment reduces bone resorption in experimental Staphylococcus aureus-induced arthritis.

Bacterial arthritis is a disease with high morbidity leading to rapidly progressive bone resorption. We have shown earlier that treatment with antibiotics in combination with corticosteroids decreases joint inflammation and mortality but does not significantly affect bone/cartilage destruction of the joints. This study was performed to assess the effect of treatment with bisphosphonate [zoledronic acid (ZA)] in combination with antibiotics and corticosteroids, on the course and outcome of Staphlococcus aureus-induced arthritis. Three days after intravenous inoculation with S. aureus, mice were treated with antibiotics alone, ZA alone, ZA and antibiotics, or ZA combined with antibiotics and corticosteroids, respectively. One group served as controls and received PBS. Clinical assessment of arthritis was performed as well as histological analysis of bone and cartilage destruction in the joints. One femur from each mouse was collected for bone mineral density (BMD) analysis. In addition, serum levels of type I collagen fragments (RatLaps), and osteocalcin, markers for osteoclastic and osteoblastic activity, respectively, were analyzed. Mice treated with ZA and antibiotics or with ZA in combination with antibiotics and corticosteroids lost significantly less in trabecular bone density compared to infected control mice. Furthermore, the addition of corticosteroids to animals treated with ZA and antibiotics, significantly decreased serum levels of RatLaps and osteocalcin, compared to animals treated with ZA and antibiotics or ZA alone. Treatment with bisphosphonates in combination with antimicrobial agents and corticosteroids significantly decreases the activity of osteoclasts in septic arthritis, thereby reducing the risk of skeletal destruction.     

Epidemiology of Injuries at a Tertiary Care Center in Malawi

Background  Injury surveillance is an ongoing process required for primary, secondary, and tertiary injury prevention. In Malawi, hospital-based injury data are not available. Methods  From February to June 2008 we collected data on injured patients presenting to Kamuzu Central Hospital in Lilongwe, Malawi. The sample (n = 1,474) was predominantly male (75.7%), and age distribution was bimodal (peak age groups <5 years and 26–30 years). Road-traffic injury (RTI) was the most common reason for treatment (43.4%), followed by assault (24.0%), which was more common than expected. The most common injuries were lacerations, contusions, and abrasions. We observed both gender- and age-specific patterns in injury mechanism: Injured females were more likely than injured males to have suffered an injury as a passenger in a car or on a bicycle, or to have suffered from falls, foreign bodies, and burns; injured males were more likely than injured females to have suffered an injury as an automobile driver or bicyclist, or from an assault. Falls, burns, and foreign bodies affected younger victims, whereas bicyclists, automobile drivers, and motorcycle operators were generally older persons. Results  The hospital admission rate was 26.8%. Most patients arrived by private vehicle (43.8%), which was also the fastest means of transportation. There were 25 mass casualties leading to 102 admissions; all but one were due to RTIs, and seven were associated with at least one fatality. Conclusions  This study elucidated injury epidemiology in Malawi and identified questions for future research. Other developing countries should conduct such prospective data collection to identify region-specific injury patterns and to promote injury prevention.     

Evaluation and Management of Patients Referred for Post-Bariatric Surgery Hypoglycemia at a Tertiary Care Center

Purpose

Following bariatric surgery, patients can develop non-specific symptoms self-described as hypoglycemia. However, confirming hypoglycemia can be technically challenging, and therefore, these individuals are frequently treated empirically. This study aimed to describe what diagnostic evaluation and therapeutic interventions patients referred for post-bariatric surgery hypoglycemia undergo.

Methods

Retrospective observational cohort study of patients with a history of bariatric surgery was evaluated for post-bariatric surgery hypoglycemia in a tertiary referral center from 2008 to 2017. We collected demographic and bariatric surgery information, clinical presentation of symptoms referred to as hypoglycemia, laboratory and imaging studies performed to evaluate these symptoms, and symptom management and outcomes.

Results

A total of 60/2450 (2.4%) patients who underwent bariatric surgery were evaluated in the Department of Endocrinology for hypoglycemia-related symptoms. The majority were middle-aged women without type 2 diabetes who had undergone Roux-en-Y gastric bypass. Thirty-nine patients (65%) completed a biochemical assessment for hypoglycemia episodes. Six (10%) had confirmed hypoglycemia by Whipple’s triad, and four (6.7%) met the criteria for post-bariatric surgery hypoglycemia based on clinical and biochemical criteria. All patients were recommended dietary modification as the initial line of treatment, and this intervention resulted in most patients reporting at least some improvement in their symptoms. Eight patients (13%) were prescribed pharmacotherapy, and two patients required additional interventions for symptom control.

Conclusions

In our experience, evaluation for hypoglycemia-related symptoms after bariatric surgery was rare. Hypoglycemia was confirmed in the minority of patients. Even without establishing a diagnosis of hypoglycemia, dietary changes were a helpful strategy for symptom management for most patients.

Graphical abstract

     

Ten-Year Experience With the Anterior Approach to Total Hip Arthroplasty at a Tertiary Care Center

BackgroundThe anterior approach (AA) to total hip arthroplasty (THA) has advantages for patients and healthcare providers. However, some studies have reported high rates of adverse events when introducing AA-THA. This was not consistent with our center’s experience, where 4 senior surgeons safely introduced AA-THA into practice. The purpose of this study is to define the adverse event rates associated with the introduction of AA-THA by a group of experienced surgeons at a single tertiary care center and define experiential factors that may modify adverse event rates.MethodsRetrospective review of prospectively collected data for an observational cohort of all patients undergoing a THA between 2006 and 2017 was conducted. Four senior surgeons at a single institution operated on 1087 primary elective hips using AA-THA.ResultsBetween 2006 and 2016, AA-THA rose from 1.5% to 53.2% of annual THA. Adverse events included intraoperative events, early postoperative periprosthetic fractures, dislocation, implant failure, early infection, and wound complications. We observed an overall 90-day adverse event rate of 6.4% (of 1087 hips). The adverse event rate was 41.6% (of 12 hips) in the first 12 months of the study period and 3.6% (of 166 hips) in the final 12 months of the study period reviewed. Sixty hips (5.5%) required a reoperation with or without revision of components, 1 (8.3%) in the first 12 months of the study period and 1 (0.6%) in the final 12 months of the study period. Infection and wound complications were the most common causes of reoperation at 1.8% for all cases (20 hips). Higher rates of adverse events are associated with early procedures (n ≤ 15) for all surgeons but showed no statistically significant impact on 5-year survival rate.ConclusionOur experience demonstrates that AA-THA can be introduced into practice with an acceptable adverse event rate when compared with other approaches to THA. As expected the incidence of adverse events is higher in the early part of the learning curve. Surgeon mentoring in the first 20 cases should be considered to minimize risk of adverse events.Level of EvidenceTherapeutic Level III.