ABSTRACT
Objective: The aim of this study is to characterise the clinical and microbiological profile of adult patients treated at our orthopaedic unit with septic arthritic between 2006 and 2017. Materials and Methods: A total of 70 patients who were admitted with a diagnosis of septic arthritis between 2006 and 2017 were included in the study. The patients' clinical and epidemiological characteristics were surveyed; microbiological profile and the complications relating to the patients' treatment were identified. Results: Septic arthritis was more common among males (83%). About 75% of the patients presented with a history of fever. The knee was the most commonly affected joint (71%), followed by the hip. While C-reactive protein was found to be consistently >75, total blood white blood cell (WBC) counts were found not to be reflective of the presence of infection with a mean WBC count of only 13,561/cu.mm, and Gram stain examination had a poor sensitivity of 47%. Among the co-morbidities, the most prevalent association was with diabetes mellitus. The infectious agent most frequently isolated was Staphylococcus aureus(42.85%). The antibiotic sensitivity pattern has evolved since the early years, with resistant strains becoming increasingly prevalent. Unusually, high incidence of streptococci was noted (30%), contrary to the published literature. One-third of the patients had multi-resistant organisms. Septic arthritis left 70% of the patients with a significant residual disability at 6 months follow-up and had 4.25% mortality. Conclusion: Changing sensitivity patterns of microbes in septic arthritis point to a need for reconsidering empirical antibiotic therapy. Joint damage following infection can lead to significant disability.
ABSTRACT
Background: Culture-negative infections in open long bone fractures are frequently encountered in clinical practice. We aimed to identify the rate and outcome of culture-negative infections in open long bone fractures of lower limb. Methodology: A prospective cohort study was conducted from November 2015 to May 2017 on Gustilo and Anderson Grade III open long bone fractures of the lower limb. Demographic data, injury details, time from injury to receiving antibiotics and index surgical procedure were noted. Length of hospital stay, number of additional surgeries and occurrence of complications were also noted. Patients with infected open fractures were grouped as culture positive or culture negative depending on the isolation of infecting microorganisms in deep intraoperative specimen. The clinical outcome of these two groups was statistically analysed. Results: A total of 231 patients with 275 open fractures involving the femur, tibia or fibula were studied. There was clinical signs of infection in 84 patients (36.4%) with 99 fractures (36%). Forty-three patients (51.2%) had positive cultures and remaining 41 patients had negative cultures (48.8%). The rate of culture-negative infection in open type III long bone fractures in our study was 17.7%. There was no statistical difference in the clinical outcome between culture-negative and culture-positive infections. Conclusion: Failure to identify an infective microorganism in the presence of clinical signs of infection is routinely seen in open fractures and needs to be treated aggressively.
ABSTRACT
Background: Prosthetic joint infection (PJI) is one of the most challenging cases that confront modern orthopaedics. Two-stage revision, which is the standard of care for PJI, is the preferred mode of treatment for these infections. Aims and Objectives: To study the microbiological profile of prosthetic joint infections (PJI) in the hip and to assess the efficacy of a two stage revision surgery for PJI. We also aimed to study the sensitivity and specificity of ESR and CRP in the diagnosis of PJI. Materials and Methods: The microbiological profile, clinical and radiological outcomes of 22 patients who had a two-stage revision for PJI of the hip between 2013 and 2017 were retrospectively analysed. PJI was defined using the criteria provided by the International Consensus Statement on PJI 2013. Results: Staphylococcus aureus was found to be the most common organism in PJI. Debridement was successful in removing the organism in 74% of PJI. At the time of re-implantation (second stage), six joints grew organisms that were different from that isolated at the index debridement - coagulase-negative staphylococci (3cases) and enterococci (3cases). Other infection parameters for these patients were negative. None of the patients who had two-stage revision surgery had clinical evidence of reinfection or radiological evidence of loosening at a mean of 2-year follow-up. An ESR cut off of >30mm/hr had a sensitivity of 75% and specificity of 88% in predicting PJI. A CRP >10mg/L had a sensitivity of 75% and specificity of 69%. The sensitivity and specificity of using both ESR and CRP cut-offs in the diagnosis of infection were 57% and 94%, respectively. The positive predictive value was 94% and negative predictive value was 56%. Conclusion: The outcomes of the study justify a two-stage revision arthroplasty for PJI of the hip. The use of ESR and CRP as screening tests for the success of debridement has value - but should be interpreted with caution.
ABSTRACT
Background: Pseudomonas aeruginosa is one of the most common opportunistic pathogens that cause severe infections in humans. The burden of carbapenem resistance is particularly high and is on the rise. Very little information is available on the molecular mechanisms and its clonal types of carbapenem-resistant P. aeruginosa seen in Indian hospitals. This study was undertaken to monitor the ?-lactamase profile and to investigate the genetic relatedness of the carbapenemase-producing (CP) P. aeruginosa collected across different hospitals from India. Materials and Methods: A total of 507 non-duplicate, carbapenem-resistant P. aeruginosa isolated from various clinical specimens collected during 2014–2017 across seven Indian hospitals were included. Conventional multiplex polymerase chain reaction for the genes encoding beta-lactamases such as extended-spectrum beta-lactamase (ESBL) and carbapenemase were screened. A subset of isolates (n = 133) of CP P. aeruginosa were genotyped by multilocus sequence typing (MLST) scheme. Results: Of the total 507 isolates, 15%, 40% and 20% were positive for genes encoding ESBLs, carbapenemases and ESBLs + carbapenemases, respectively, whilst 25% were negative for the ?-lactamases screened. Amongst the ESBL genes, blaVEB is the most predominant, followed by blaPER and blaTEM, whilst blaVIM and blaNDM were the most predominant carbapenemases seen. However, regional differences were noted in the ?-lactamases profile across the study sites. Genotyping by MLST revealed 54 different sequence types (STs). The most common are ST357, ST235, ST233 and ST244. Six clonal complexes were found (CC357, CC235, CC244, CC1047, CC664 and CC308). About 24% of total STs are of novel types and these were found to emerge from the high-risk clones. Conclusion: This is the first large study from India to report the baseline data on the molecular resistance mechanisms and its association with genetic relatedness of CP P. aeruginosa circulating in Indian hospitals. blaVIM- and blaNDM-producing P. aeruginosa is the most prevalent carbapenemase seen in India. Majority of the isolates belongs to the high-risk international clones ST235, ST357 and ST664 which is a concern.