Clinical and epidemiological characteristics of septic arthritis of the hip, 2006 to 2012, a seven-year review

Detection of bacterial DNA in synovial fluid in dogs with arthritis: a comparison between bacterial culture and 16S rRNA polymerase chain reaction

Background

Septic arthritis (SA) is a serious condition in dogs that requires a prompt diagnosis and treatment to minimize long-term joint pathology. Although bacterial detection in synovial fluid (SF) through culture or cytology is often performed to confirm diagnosis, the sensitivity of these tests is low. The need for a reliable diagnostic tool to confirm the presence of bacteria in SF in humans has led to the increased use of 16S rRNA (i.e., ribosomal RNA) gene sequencing by polymerase chain reaction (16S rRNA PCR). The aim of this prospective clinical study was to compare the sensitivity and specificity of 16S rRNA PCR with bacterial culture on blood agar plates after pre-incubation of SF in paediatric blood bacterial culture bottles to identify bacteria in dogs with clinical signs of SA and to investigate the usefulness of these methods as diagnostic tools.

Results

Ten dogs with clinical signs of SA, nine with osteoarthritis (OA, control group) and nine with clinical signs of immune-mediated polyarthritis (IMPA, second control group) were examined. Bacterial culture was positive in seven of 10 dogs with clinical SA, of which only two were positive by 16S rRNA PCR. The sensitivity of 16S rRNA PCR and bacterial culture analysis for dogs with clinical SA were 20% and 70%, respectively. All SF samples collected from control group (n = 9) and second control group (n = 14) animals were negative on culture, and 16S rRNA PCR rendered a specificity of 100%.

Conclusions

Our study showed a lower sensitivity of 16S rRNA PCR than bacterial culture for dogs with clinical SA. Our findings suggest that there is currently no advantage in using 16S rRNA PCR as a diagnostic tool for dogs with clinical SA. Furthermore, our study indicates that pre-incubation in paediatric blood bacterial culture bottles before bacterial cultivation on blood agar plates might enhance bacterial culture sensitivity compared to other culture methods.

The impact of gender on the clinical presentation, management, and surgical outcomes of patients with native-joint septic arthritis

RATIONALE, AIMS AND OBJECTIVES

Approximately 20 000 cases of septic arthritis (SA) occur in the U.S. yearly. We examined whether gender-related differences exist in the presentation, management, and outcomes of patients with native joint septic arthritis (NJSA).

METHODS

This was a retrospective study of medical files of patients aged 18 years and older admitted between 1998 and 2015 to a single tertiary care hospital and diagnosed with NJSA. All study subjects had positive synovial fluid or blood cultures and each was managed surgically. Patients' charts were reviewed for demographics, comorbidities, clinical presentations, microbiology profiles, management, and outcomes. Cases of osteomyelitis, septic bursitis, prosthetic joint, and culture-negative SA were excluded.

RESULTS

Of 324 NJSA patients, those who were female (n = 130; 40.1%) were significantly older at presentation than males (mean age: 63.6 vs 58.3; P = .006). Prior joint pathology was more common amongst females, including osteoarthritis (20.8% vs 12.9%; P = .04) and rheumatoid arthritis (10% vs 3.6%; P = .03). Female patients had a higher frequency of hip involvement (17.7% vs 10.8%; P = .05). No differences were observed in clinical presentations, culture results, medical management, or outcomes between genders.

CONCLUSIONS

Compared to men, women with NJSA presented at an older age and had more prior joint pathology and a higher frequency of hip involvement. These differences, however, had no significant impact on the clinical presentation, medical management, or outcomes of NJSA.

Efficacy and safety of arthroscopic treatment for native acute septic arthritis of the hip joint in adult patients

Background

As septic arthritis is time-dependent and has a propensity for irreversible joint damage, early diagnosis and treatment are needed. Frequently, adult patients with septic arthritis cannot undergo invasive surgery because of comorbidities and a weakened immune system. Hip arthroscopic irrigation and debridement for native acute septic arthritis of the hip joint have been performed as the first choice of treatment for patients of all ages. This study aimed to assess the efficacy and safety of arthroscopic management for native acute septic arthritis of the hip joint in adult patients.

Methods

Five adult patients (mean age, 46.2 years; all male) were retrospectively reviewed. Immediately after diagnosis, all patients underwent hip arthroscopic irrigation, debridement with synovectomy, and drainage. Partial weight-bearing was permitted once the C-reactive protein level normalised to < 1.0 mg/dl. Preoperative comorbidities, bacterial culture results, surgical complications, duration of hospital stay, time-to-confirmed normalisation of the C-reactive protein level, and recurrence incidence were evaluated.

Results

All patients had comorbidities, and the cultured microorganisms differed among cases. There were no complications related to arthroscopic surgery. All patients achieved confirmed C-reactive protein normalisation within an average of 69.8 days, and there was no recurrence during the follow-up period (mean, 40.2 months; range, 16–60 months).

Conclusion

Arthroscopic management for native acute septic arthritis of the hip joint is a safe and effective procedure in adult patients.

Diagnosis and Management of Infectious Arthritis in Children

PURPOSE OF REVIEW

Septic arthritis is limb and life-threatening condition which necessitates rapid diagnosis and treatment. It is important for a medical practitioner to be familiar with this condition. This review summarizes the epidemiology, risk factors, diagnosis and differential diagnosis, complications, as well as treatment and the following-up of this condition.

RECENT FINDINGS

Different causative organisms require unique diagnostic and treatment approaches. Establishing the diagnosis often requires multiple diagnostic modalities, some of which are new and innovative. Differential diagnosis requires excluding non-infectious inflammatory causes, such as reactive arthritis, juvenile rheumatoid arthritis, transient synovitis, and pericapsular pyomyositis. There is no consensus regarding the nature or duration of pharmacological or surgical treatment. Treatment includes administration of appropriate antimicrobial therapy and including the use of steroids and drainage. The most common complications are osteonecrosis of the femoral head and chronic osteomyelitis. Complications of septic arthritis are mostly due to a missed diagnosis. Further studies are required to better evaluate the diagnostic and therapeutic choice.

Comparison of efficacy and complications between two types of staging arthroplasty in treating chronic septic hip arthritis: A retrospective clinical study

Septic hip arthritis is a rare but serious disease, which is often persistent, able to transform into a chronic infection, and difficult to cure. The present study aimed to compare the midterm outcomes between the staging of a total hip arthroplasty via the Girdlestone surgery (a resection of the head and neck) and the Girdlestone combined with a cement spacer in treating chronic septic hip arthritis, as well as to compare the postsurgery efficacy and complications between the two groups. A total of 13 patients (14 total hip joints) were enrolled and retrospectively analyzed. For the stage I surgery, four patients (five hips) underwent the resection of the head and neck, and nine patients (nine hips) underwent the resection of the head and neck combined with the implantation of a bone cement spacer. After the infection was fully controlled, the patients in both groups underwent cementless total hip arthroplasties as stage II surgeries. The mean follow-up period was 24.2 months. The curative effects and complications of the patients were recorded and compared. It was found that the application of the staging arthroplasty for treating a chronic septic hip was conducive to the complete clearance of lesions. Notably, the implantation of a bone cement spacer containing antibiotics in the stage I surgery prevented joint contracture caused by a head and neck resection, reducing the risk of infection recurrence between the two stages of the operation. This effectively maintained the length of the lower limbs, simplified the stage II complete hip arthroplasty and reduced operative hemorrhage, thus achieving improved recovery of joint function after the stage II arthroplasty. The results suggested that the implantation of a cement spacer at the stage I surgery was more effective in treating chronic septic hip arthritis.

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.

Septic arthritis of the knee: clinical and laboratory comparison of groups with different etiologies

OBJECTIVES:

To clinically and epidemiologically characterize a population diagnosed with and treated for septic arthritis of the knee, to evaluate the treatment results and to analyze the differences between patients with positive and negative culture results, patients with Gram-positive and Gram-negative bacterial isolates and patients with S. aureus- and non-S. aureus-related infections.

METHODS:

One hundred and five patients with septic knee arthritis were included in this study. The clinical and epidemiological data were evaluated. Statistical analysis was performed to compare patients with and without an isolated causative agent, patients with Gram-positive and Gram-negative pathogens and patients with S. aureus-related and non S. aureus-related infections.

RESULTS:

Causative agents were isolated in 81 patients. Gram-positive bacteria were isolated in 65 patients and Gram-negative bacteria were isolated in 16 patients. The most commonly isolated bacterium was S. aureus. Comparing cases with an isolated pathogen to cases without an isolated pathogen, no differences between the studied variables were found except for the longer hospital stays of patients in whom an etiological agent was identified. When comparing Gram-positive bacteria with Gram-negative bacteria, patients with Gram-positive-related infections exhibited higher leukocyte counts. Patients with S. aureus-related infections were more frequently associated with healthcare-related environmental encounters.

CONCLUSION:

S. aureus is the most common pathogen of septic knee arthritis. Major differences were not observed between infections with isolated and non-isolated pathogens and between infections with Gram-positive and Gram-negative bacteria. S. aureus infections were more likely to be associated with a prior healthcare environment exposure.

Ultrastructural changes in methicillin-resistant Staphylococcus aureus induced by positively charged silver nanoparticles

Silver nanoparticles offer a possible means of fighting antibacterial resistance. Most of their antibacterial properties are attributed to their silver ions. In the present work, we study the actions of positively charged silver nanoparticles against both methicillin-sensitive Staphylococcus aureus and methicillin-resistant Staphylococcus aureus. We use aberration-corrected transmission electron microscopy to examine the bactericidal effects of silver nanoparticles and the ultrastructural changes in bacteria that are induced by silver nanoparticles. The study revealed that our 1 nm average size silver nanoparticles induced thinning and permeabilization of the cell wall, destabilization of the peptidoglycan layer, and subsequent leakage of intracellular content, causing bacterial cell lysis. We hypothesize that positively charged silver nanoparticles bind to the negatively charged polyanionic backbones of teichoic acids and the related cell wall glycopolymers of bacteria as a first target, consequently stressing the structure and permeability of the cell wall. This hypothesis provides a major mechanism to explain the antibacterial effects of silver nanoparticles on Staphylococcus aureus. Future research should focus on defining the related molecular mechanisms and their importance to the antimicrobial activity of silver nanoparticles.

Clinical and epidemiological differences between septic arthritis of the knee and hip caused by oxacillin-sensitive and -resistant s. aureus

OBJECTIVE

To establish the risk factors for joint infection by oxacillin-resistant Staphylococcus aureus (MRSA) using clinical and epidemiological data.

METHODS

All septic arthritis cases of the knee and hip diagnosed and treated in our institution from 2006 to 2012 were evaluated retrospectively. Only patients with cultures identified as microbial agents were included in the study. The clinical and epidemiological characteristics of the patients were analyzed, seeking the differences between populations affected by MRSA and oxacillin-sensitive Staphylococcus aureus (MSSA).

RESULTS

S. aureus was isolated in thirty-five patients (46.0%) in our total sample, 25 in the knee and 10 in the hip. Of these 35 patients, 22 presented with MSSA and 13 presented with MRSA. Provenance from a health service-related environment, as described by the Centers for Disease Control and Prevention, was the only variable associated with oxacillin-resistant strains of this bacterium (p = 0.001).

CONCLUSION

Provenance from a health service-related environment was associated with a higher incidence of MRSA-related septic arthritis, suggesting that this agent should be considered in the initial choice of antibiotic treatment. Previous surgeries of the knee or affected limb and the absence of leukocytes might also be related to infection with this agent.