Deep Tissue Cultures Research Articles

Infections after musculoskeletal injuries in earthquake survivors.

This study aimed to investigate the infections following musculoskeletal injuries in earthquake survivors, offering a future clinical point of reference for the handling of musculoskeletal injuries resulting from earthquakes. In this single-center retrospective observational study, 225 earthquake survivors (120 females, 105 males; median: 39 years; range, 18 to 94 years) admitted between February 2023 and April 2023 were evaluated. Patients with musculoskeletal injuries and patients who had at least one month of follow-up data were included in the study. Diagnosis of healthcare-associated infections was verified by an infection control physician in accordance with the Centers for Disease Control and Prevention. Among all cultures, the most isolated pathogen was Acinetobacter baumannii (49.4%), followed by enterococci (28.6%). Colistin sensitivity of A. baumannii was 36 (94.7%). However, sensitivity rate was 5.3% for ciprofloxacin, 10.5% for piperacillin-tazobactam, and 26.4% for carbapenems, which are frequently used for skin and soft tissue infections. Among all, 76% of the microorganisms isolated from wound culture and 58% of the microorganisms isolated from deep tissue culture were found to be multidrug-resistant pathogens. During the follow-up, 12 (5.3%) patients had hospital-acquired urinary tract infections, 13 (5.7%) patients had hospitalacquired bloodstream infections, one (0.4%) patient had hospital-acquired pneumonia, and 74 (32.8%) patients had surgical site infections. Eighty (35.6%) of the patients were followed up in the intensive care unit, and the overall mortality rate was 2.7%. While gram-positive microorganisms are frequently the causative microorganisms in infections after traumatic injuries, this study revealed that gram-negative microorganisms could be observed more frequently in postearthquake traumatic injuries. Most causative microorganisms are resistant to commonly prescribed antibiotics in clinical settings, which makes them more challenging to treat.

What Is the Rate of Antimicrobial Resistance of a Prosthetic Joint Infection in a Major Orthopaedic Centre?

Periprosthetic joint infections (PJIs) are important factors in decreasing the success of hip and knee arthroplasties. It is a necessity to explore the epidemiological data and develop applications for rational antibiotic use, to address future infection control concerns. We aimed to investigate the microorganisms that were responsible and the related antibiograms in 121 patients with PJI, who were managed by two-stage revision surgery. Patients' data records, demographics, comorbidities, sites of arthroplasty, synovial fluid and deep tissue culture results and antibiotic treatment were summarized on a standardized case report form. There were 43 (35.5%) culture-negative PJI cases and 12 (9.9%) polymicrobial growths. The causative pathogens included Gram-positive (50.4%) and Gram-negative microorganisms (23.1%) and fungi (0.8%). Methicillin resistance was 64.3% for S. aureus and 89.5% for coagulase-negative staphylococcus (CoNS). The extended spectrum beta lactamase (ESBL) rate for Enterobacteriaceae was 68.4%. This study shows that antibiotic resistance is encountered in more than half of the cases, which is valid for all microorganisms most common in PJI. The success of treatment decreases significantly in cases where antibiotic-resistant microorganisms are isolated or in cases where the culture is negative.

Serum Galactomannan as a Minimally Invasive Diagnostic Tool for Fungal Skull Base Osteomyelitis.

Multidrug resistant strains and fungi add to treatment conundrums in skull base osteomyelitis (SBO). Deep tissue culture in these patients is challenging due to their advanced age and co-morbidities. Besides, fungal culture positivity is seen only in 60% of invasive aspergillosis. To determine the efficacy of a minimally invasive test-Serum Galactomannan (sGM)-for diagnosing fungal SBO. Prospective observational study. Thirty- three patients, clinically diagnosed with SBO were included in this study. Baseline ESR (Erythrocyte Sedimentation Rate), CRP (C- Reactive Protein), pain score, and sGM were noted for all patients. Antifungal Voriconazole was initiated on patients if the sGM values were more than 0.8. At the 12th week of treatment, all parameters were repeated and compared with the baseline values. A significant reduction was noted in ESR, CRP, and pain scores at the 12th week of treatment compared to the baseline values in patients with raised sGM values who were started on Voriconazole. For a culture-proven fungal skull base osteomyelitis with a cut-off value of sGM > / = 0.8, the obtained sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were 81.82, 36.36, 39.13, 80 and 51.52% respectively. At a cut-off value of sGM > / = 01.6, the values of sensitivity/specificity, PPV, NPV and accuracy were 81.82/72.73%, 60%, 88.89% and 75.76%. Culture-negative patients in SBO with sGM value > 0.8 were more likely to be fungal SBO. An sGM cut-off of 1.6 was observed to give maximum accuracy for diagnosing fungal SBO.

Microbiological Evaluation of Paediatric Chronic Haematogenous Osteomyelitis in a Tertiary Care Hospital in Northern India and its Association with Radiological Appearance: A Retrospective Study

Introduction: Chronic osteomyelitis in the paediatric age group is a frequent complication of improperly treated acute haematogenous osteomyelitis, leading to devastating complications such as pathological fractures and deformities in affected children. There is a growing need to comprehend the disease process and develop improved treatment strategies. Aim: To evaluate bacterial culture and antibiotic sensitivity patterns in children and adolescents with chronic haematogenous osteomyelitis in North India and to explore associations between radiological patterns and antibiotic sensitivity. Materials and Methods: The present retrospective study was conducted in the Department of Orthopaedics of tertiary care centre, Himalayan Institute of Medical Sciences, Dehradun, Uttarakhand, North India, from July 2018 to June 2020. Total 100 children and young adolescents with chronic osteomyelitis who reported to OPD of hospital with pus discharge from an extremity persisting for more than six weeks, along with radiological features indicative of chronic osteomyelitis. Parameters such as site of infection, illness duration, blood parameters, bacteriological culture reports, etc., were examined. Radiological evaluation was performed using the Beit CURE (BC) classification. Data were analysed and represented in the form of frequencies and percentages. The Chi-square test was used to compare proportions, with significance set at p-value<0.05. Results: The median age of the study population was 13 years, there were 32 (32%) females and 68 (68%) males. The majority of cases (70%) belonged to the B1-B3 group. Staphylococcus aureus was responsible for 86 (86%) cases, followed by Pseudomonas aeruginosa in 7 (7%) cases. Out of the 86 Staphylococcus aureus (S. aureus) isolates, 58 (67.44%) were Methicillin-resistant Staphylococcus aureus (MRSA). Multidrug resistance was observed among gram-negative species, as well. Pseudomonas aeruginosa showed resistance to fluoroquinolones in 4 (57%) cases, aminoglycosides in 2 (28%) cases, and carbapenem in 1 (14%) case, which is considered highly effective in treating serious infections caused by multidrug resistant Gram-negative species. No significant association was found between drug sensitivity patterns and radiological features in the present study. Conclusion: Staphylococcus aureus remains the most predominant organism isolated from deep tissue cultures. Among S. aureus isolates, MRSA was the most frequently identified. Identifying the causative organism may be challenging in some cases. Among cases where the offending microbe was identified, drug resistance was widespread among both Gram-negative and Gram-positive specimens. No significant relationship was found between the radiological appearance of infected bone and the pattern of antibiotic resistance.

Functional outcomes and complications of patients contaminated with Cutibacterium acnes during primary reverse shoulder arthroplasty: study at two- and five-years of follow-up.

The objective of the study was to compare the functional outcomes and the complication rate of the patients with C. acnes contamination at the end of the primary reverse shoulder arthroplasty (RSA) surgery to those patients without C. acnes contamination. A total of 162 patients were included. In all cases, skin and deep tissue cultures were obtained. A molecular typing characterization of the C. acnes strains was performed. Functional outcomes were assessed with the Constant score at the two and fiveyear follow-up and all complications were also recorded. A total of 1380 cultures were obtained from the 162 primary RSA surgeries. Of those, 96 turned out to be positive for C. acnes. There were 25 patients with positive cultures for C. acnes. The overall postoperative Constant score was not significantly different between those patients having C. acnes-positive cultures and those with negative cultures at the two and fiveyear follow-up (59.2 vs. 59.6 at two years, p 0.870, and 59.5 vs. 62.4 at five years, p 0.360). Patients with positive cultures presented a higher complication rate (p 0.001) with two infections, one revision surgery, and one dislocation. Patients ending up with C. acnes-positive cultures after primary shoulder arthroplasty surgery do not have worse clinical outcomes when compared to patients having negative cultures, but a greater number of complications were found in those patients with C. acnes-positive cultures.

Concordance of bone culture and deep tissue culture during the operation of diabetic foot osteomyelitis and clinical characteristics of patients.

To retrospectively analyze the concordance of bacterial culture between bone tissue and deep soft tissue in diabetic foot osteomyelitis (DFO) patients and clinical characteristics of patients. This study collected samples from 155 patients with suspected DFO (who required amputation after clinical evaluation). Bacterial culture and drug susceptibility tests were performed on the patients' deep soft tissue and bone tissue, and the consistency between the two was compared. In addition, the differences among DFO patients with different degrees of infection were compared classified by the PEDIS classifications. Among the 155 patients diagnosed with DFO, the positive rate of bone culture was 78.7% (122/155). This study cultured 162 strains, including 73 Gram-positive bacteria, 83 Gram-negative bacteria, and 6 fungi. Staphylococcus aureus (33 strains) was the most common bacteria. The overall agreement between bone culture and tissue culture was 42.8%, with Staphylococcus aureus and Enterobacteria having the best (64.3%) and least agreements (27.3%), respectively. The drug sensitivity results in bone culture showed that Staphylococcus aureus was the main Gram-positive bacteria. The bacteria were sensitive to linezolid and vancomycin. Proteus mirabilis was the main Gram-negative bacteria. These were more sensitive than biapenem and piperacillin/tazobactam. Fungi were more sensitive to voriconazole and itraconazole. The culture results of deep soft tissues near the bone cannot accurately represent the true pathogen of DFO. For DFO patients, bone culture should be taken as much as possible, and appropriate antibiotics should be selected according to the drug susceptibility results.

Most postoperative reserved "normal" metatarsal stumps of diabetic foot osteomyelitis are infected but have healing potential.

Although the pathology and bacterial status of the "normal" bone stump after operation of diabetic foot osteomyelitis (DFO) are of great significance for the prognosis of foot wounds, there are only a few studies on this topic; hence, it is clinically relevant and urgent to study this topic. The data of 57 inpatients with DFO from June 2021 to April 2022 were collected, all of whom had DFO in the forefoot and underwent conservative surgery. After the surgical removal of necrotic bone, bone biopsies were taken from the necrotic phalangeal bone and the reserved "normal" metatarsal stump. They were cultured, after which antibiotic susceptibility test and pathological screening were carried out. According to clinical judgment, inpatients' wounds were divided into metatarsal affected group and metatarsal unaffected group. We then compared and analyzed the pathological and bacterial characteristics of preserved "normal" bone stump and its effect on wound healing and prognosis. The poor concordance rate between deep soft tissue culture and infected phalange culture was only 19.3%. The deep soft tissue (72.6%), infected phalange (70.7%), and metatarsal stump (71.4%) were mainly infected with gram-negative Bacillus. The proportion of Enterococcus spp. increased significantly in bone tissue. Acinetobacter baumannii had the highest drug resistance (88%, 22/25). There was no significant difference in several clinical characteristics and wound healing regardless of whether their metatarsal stumps were affected. Most reserved "normal" metatarsal stumps (84.2%, 48/57) were positive by pathological diagnosis and bacterial culture testing; only 15.7% (9/57) samples were truly sterile. Only 8.3% (4/48) of the former patients healed within 6 months; whereas, all the latter (9/9) patients healed within 6 months. However, the majority (89.6%, 43/48) could heal. There was no difference in operations, skin grafting, negative pressure wound therapy, and mortality between the two groups. The most reserved "normal" metatarsal stumps have been invaded by bacteria. However, the majority stumps can be preserved, and the wound will eventually be healed according to the pathological and bacterial culture results.

Diagnosis of fracture-related infection in patients without clinical confirmatory criteria: an international retrospective cohort study.

Background: fracture-related infection (FRI) remains a serious complication in orthopedic trauma. To standardize daily clinical practice, a consensus definition was established, based on confirmatory and suggestive criteria. In the presence of clinical confirmatory criteria, the diagnosis of an FRI is evident, and treatment can be started. However, if these criteria are absent, the decision to surgically collect deep tissue cultures can only be based on suggestive criteria. The primary study aim was to characterize the subpopulation of FRI patients presenting without clinical confirmatory criteria (fistula, sinus, wound breakdown, purulent wound drainage or presence of pus during surgery). The secondary aims were to describe the prevalence of the diagnostic criteria for FRI and present the microbiological characteristics, both for the entire FRI population. Methods: a multicenter, retrospective cohort study was performed, reporting the demographic, clinical and microbiological characteristics of 609 patients (with 613fractures) who were treated for FRI based on the recommendations of a multidisciplinary team. Patients were divided in three groups, including the total population and two subgroups of patients presenting with or without clinical confirmatory criteria. Results: clinical and microbiological confirmatory criteria were present in 77 % and 87 % of the included fractures, respectively. Of patients, 23 % presented without clinical confirmatory criteria, and they mostly displayed one (31 %) or two (23 %) suggestive clinical criteria (redness, swelling, warmth, pain, fever, new-onset joint effusion, persisting/increasing/new-onset wound drainage). The prevalence of any suggestive clinical, radiological or laboratory criteria in this subgroup was 85 %, 55 % and 97 %, respectively. Most infections were monomicrobial (64 %) and caused by Staphylococcus aureus. Conclusion: clinical confirmatory criteria were absent in 23 % of the FRIs. In these cases, the decision to operatively collect deep tissue cultures was based on clinical, radiological and laboratory suggestive criteria. The combined use of these criteria should guide physicians in the management pathway of FRI. Further research is needed to provide guidelines on the decision to proceed with surgery when only these suggestive criteria are present.

Protruded Rode Post Posterior Spinal Fusion in Scoliosis Patient – Case Report

Scoliosis is defined as coronal plane spinal deformity. It is known as the lateral angulation of the vertebra more than 10 degrees which most commonly presents in adolescent girls from age 10 to 18. Scoliosis is divided into two groups which are congenital and idiopathic Scoliosis. We present a case of 18 years old male patient known as mental delayed and cleft palate, complaining of protruded Hardware for three years as post-T4 to L2 Posterior Spinal Fusion who diagnosed as a neuromuscular Scoliosis. The patient lost to follow-up since staples removal and came to the clinic after three years as transferred from primary health care. Upon physical examination, intact motor and sensory exam and normal reflexes, no signs of infection. A serial radiological investigation was ordered, and blood work was done as well. Irrigation and, debridement and hardware removal were performed, the four left proximal pedicle screws were removed. The proximal cutting part of the left rod. Deep tissue culture from different sites was taken for culture and sensitivity, which was positive for staphylococcus Aureus. The patient was kept in the hospital for intravenous antibiotics and seen in the clinic for follow-up. This case report suggests noncompliance can affect the outcome and lead to severe complications. We present a case of protruded rode post scoliosis correction in which underwent removal of loose left four pedicle screws and proximal rode.

Comparison of Microbiological Results of Superficial Swab versus Deep Tissue Biopsy in Diabetic Foot Infections: A Prospective Observational Study from North India

Introduction: Diabetes mellitus is the leading cause of nontraumatic lower extremity amputation worldwide. Risk of developing a foot ulcer in diabetic patients has increased to 12-25% during their lifetime. Inappropriate sampling technique leading to contaminated samples is a well-known threat among patients of diabetic foot. In this study we compared two microbiological sampling techniques, superficial swabbing and deep tissue biopsy for identification of pathogens. Material and Methods: It was a prospective observational cross-sectional study. Diabetic foot was defined as per standard guidelines. Careful and meticulous examination of diabetic foot ulcer was done. Two specimens were collected from each wound. The first specimen was a wound swab collected by using Levine technique; another was taken via punch biopsy from the ulcer base. It was a deep tissue sample of 4 mm size. Results: A total of 120 diabetic patients with diabetic foot infection were included in this study. In swab culture 80.83% patients had mono microbial growth, 15% had polymicrobial and 4.10% had no growth. In deep tissue culture 87.50% had mono microbial growth, 2.50% had poly microbial and 10% were sterile. Staphylococcus aureus was most common isolate followed by E. coli. It was observed that though monomicrobial growth was most common in both the types of samples but was higher in deep tissue biopsy than in superficial swab samples. Conclusion: The isolation of microorganism via deep tissue sampling in diabetic foot ulcer patients is more reliable compared to superficial swab samples and a better guide to antibiotic therapy.

Minimal number of cultures needed to detect Cutibacterium acnes in primary reverse shoulder arthroplasty: a prospective study.

The objective of this study was to determine the minimum number of cultures needed to detect Cutibacterium acnes in primary reverse shoulder arthroplasties (RSAs). It is a prospective study including 160 primary RSAs. Exclusion criteria included an active infection, an invasive shoulder treatment in the last 6 months before surgery, an Arthro-SCAN or Arthro-MRI in the last 6 months before surgery, previous shoulder surgeries and revision cases. In 90 cases, 11 cultures were obtained. Another 10 cultures were obtained in the other 70 cases (culture 10 was a sterile sponge to detect false positives). To determine the minimum number of cultures needed to detect C acnes, the prevalence of C acnes contamination of the 160 patients included was determined. There were 128 females and 32 males, with a mean age of 74 years. There were 1690 cultures obtained from the 160 primary RSA surgeries, and 132 of them turned out to be positive for C acnes. There were 42 patients with positive cultures. Twenty of them were males and 22 females. When considering the skin and the deep tissue cultures altogether, the prevalence of positive cultures for C acnes was of 26.25%. If only deep tissues cultures were considered, the prevalence of positive cultures for C acnes was of 23.13%. When considering the skin and the deep tissue cultures together, the sensitivity to detect the C acnes is 19% if only 1 culture is obtained, 31% if 2 cultures are obtained, 50% if 3 cultures are obtained, 59.5% if 4 cultures are obtained, 66.7% if 5 cultures are obtained, 73.8% if 6 cultures are obtained, 85.7% if 7 cultures are obtained, and 92.9% if 8 cultures are obtained. When considering only the deep tissue cultures, if only 1 culture is obtained, the sensitivity to detect the C acnes is 24.3%, 40.5% if 2 cultures are obtained, 54.1% if 3 cultures are obtained, 73% if 4 cultures are obtained, 89.2% if 5 cultures are obtained, and 97.3% if 6 or 7 cultures are obtained. A minimum number of 8 cultures are needed to detect C acnes in skin. Moreover, a minimum of 6 cultures are needed to detect it in deep tissues when performing an RSA.

Foot Abscesses With No Accompanying Wound: Clinical Presentation and Pathogens

Introduction. Acute bacterial infections of the skin and soft tissue are common and often pose serious complications, most commonly caused by Streptococcus species and Staphylococcus aureus. Objective. The authors report clinical presentation and pathogens in patients with a foot abscess and no wound. Methods. The authors retrospectively evaluated the demographics, clinical presentation, and microbiology from 20 patient records. Results. Twenty patients were identified. Fifteen were male (75%), and 10 patients (50%) had DM. Patients presented to the hospital 7.8 ± 4.8 days after onset of symptoms and underwent surgery 2.0 ± 0.9 days from admission. Patients underwent 2.4 ± 1.0 surgeries while admitted. Patients with DM presented with significantly higher erythrocyte sedimentation rate than patients without DM (66.6 ± 46.1 vs 43.3 ± 26.2; P = .02). There were no polymicrobial infections based on deep intraoperative tissue cultures. Seven patients had methicillin-sensitive S aureus (35%), 4 had Streptococcus agalactiae (20%), 3 had methicillin-resistant S aureus (15%), 1 had Streptococcus pyogenes (5%), 1 had Escherichia coli (5%), 1 had Streptococcus dysgalactiae (5%), 1 had an unidentified Streptococcus species (5%), and 2 had no growth (10%). Conclusion. Patients with foot abscess and no wounds had single-pathogen infections, predominantly Staphylococcus and Streptococcus.

989. Role of Bone Biopsy and Deep Tissue Culture for Antibiotic Stewardship in Diabetic Foot Infections

Abstract Background Bone biopsy is the gold standard for identifying the etiology of infectious osteomyelitis (OM) but is not always done in the setting of diabetic foot infections (DFIs), even in settings where resistant organisms are common. This study aimed to describe organisms most frequently identified on bone biopsy or deep tissue culture and determine how culture data impacted antibiotic management in patients with DFIs. Methods We retrospectively reviewed all patients admitted with a DFI between 2018 and 2020 and selected for patients diagnosed with infectious OM of the lower extremity for whom bone biopsy or deep tissue culture was obtained. Statistics were performed in R version 4.2.0. Results Of 305 patients with DFI, 47 patients received 41 deep tissue cultures and 29 bone biopsies for a total of 70 cultures. Of 45 (64%) positive cultures, 36 (80%) had gram positive organisms and 24 (34%) had gram negative organisms. Multidrug resistant organisms were isolated in 7 (14.9%) patients, including 5 cases of MRSA (10.2%) and 2 cases of ESBL-producing organisms (4.3%). Pseudomonas aeruginosa was isolated in 3 (6.4%) patients. Culture data resulted in antibiotic changes in 41 (87.2%) patients. Therapy was narrowed in 29 (61.7%) patients and broadened due to inadequate empiric coverage in 4 patients (8.5%). Culture-directed therapy was started in 4 (8.5%) patients in which it had initially been withheld. Culture data from 18 (40%) patients showed sensitivity to an oral treatment regimen with high bioavailability. There was no significant difference in rates of antibiotic utilization at discharge between patients who underwent bone biopsy or deep tissue culture relative to those who did not (80% vs 75%, p=0.857). There was a trend towards utilization of less MRSA coverage (38.2% vs 50.5%, p=0.16) and Pseudomonas coverage (34.0% vs 41.9%, p=0.36) in patients undergoing bone biopsy or deep tissue culture, but this did not reach statistical significance. Table 1:Bacteria isolated from deep tissue culture or bone biopsy and effect on antibiotic therapyFigure 1:Empiric antibiotics in hospital vs culture directed antibiotics on discharge Conclusion In patients with DFIs, deep tissue and bone biopsy cultures were infrequently obtained but resulted in targeted therapy changes in most patients. While culture data usually allowed for narrowing of antibiotics, it revealed inadequate empiric coverage in a subset of patients. Disclosures Janna L. Williams, MD, Abbvie: COVID19 Infection Prevention Consultant Shannon Galvin, MD, Gilead: Grant/Research Support.

Role of bone biopsy and deep tissue culture for antibiotic stewardship in diabetic foot osteomyelitis.

To describe organisms most frequently identified on bone biopsy or deep tissue culture and determine how culture data impacted antibiotic management in patients with diabetic foot osteomyelitis (DFO). We retrospectively reviewed patients admitted with a diabetic foot ulcer (DFU) between 3 March 2018 and 31 December 2019 and selected for patients diagnosed with infectious osteomyelitis (OM) of the lower extremity. We stratified patients by whether a bone biopsy or deep tissue culture was obtained and compared rates of antibiotic utilization with chi-squared and Fisher's exact tests. Of 305 patients with a DFU, 152 (50%) were clinically diagnosed with DFO. Forty-seven patients received 41 deep tissue cultures and 29 bone biopsy cultures for a total of 70 cultures. Of 45 (64%) positive cultures, 36 (80%) had Gram-positive organisms and 19 (42%) had Gram-negative organisms. MDR organisms were isolated in 7 (15%) patients. Culture data resulted in antibiotic changes in 41 (87%) patients. Therapy was narrowed in 29 (62%) patients and broadened due to inadequate empirical coverage in 4 (9%) patients. Culture data from 18 (40%) patients showed susceptibility to an oral treatment regimen with high bioavailability. There was no significant difference in rates of antibiotic utilization at discharge between patients who underwent bone biopsy or deep tissue culture relative to those who did not (77% versus 75%, P = 0.86), although less MRSA coverage was used (34% versus 50%, P = 0.047). In patients with DFO, deep tissue and bone biopsy cultures were infrequently obtained but resulted in targeted therapy changes in most patients. Culture data usually allowed for narrowing of antibiotics but revealed inadequate empirical coverage in a subset of patients.

Culturing explants for Cutibacterium at revision shoulder arthroplasty: an analysis of explant and tissue samples at corresponding anatomic sites.

Culturing of deep tissues obtained at revision arthroplasty for Cutibacterium is a key component of diagnosing a periprosthetic infection. The value of culturing explanted components has not been well described. This study sought to answer the following questions: (1) How does the culture positivity of explant cultures compare with that of deep tissue cultures? (2) How often are explant cultures positive when tissue cultures are not, and vice versa? (3) How does the bacterial density in explant cultures compare with that in tissue cultures? A total of 106 anatomic arthroplasties revised over a 7-year period were included. Explant (humeral head, humeral stem, and glenoid) and tissue (collar membrane, humeral canal tissue, and periglenoid tissue) specimens were sent for semiquantitative Cutibacterium culture. We compared culture positivity and bacterial density when cultures of an explant and tissue adjacent to the implant were both available. Explants had positive cultures at a higher rate than adjacent tissue specimens for most anatomic sites. Of the shoulders that had Cutibacterium growth, a higher proportion of explants were culture positive when tissue samples were negative (23%-43%) than vice versa (0%-21%). The Cutibacterium density was higher in explants than in tissues. Considering only the results of tissue samples, 16% of the shoulders met our threshold for infection treatment (≥2 positive cultures); however, with the inclusion of the results for explant cultures, additional 14% of cases-a total of 30%-met the criteria for infection treatment. In this group of patients, culturing explants in addition to tissue cultures increased the sensitivity for detecting Cutibacterium in revision shoulder arthroplasty.

What do positive and negative Cutibacterium culture results in periprosthetic shoulder infection mean? A multi-institutional control study.

Deep tissue culture specimens obtained at the time of revision shoulder arthroplasty are commonly positive for Cutibacterium. Clinical interpretation of positive cultures can be difficult. This was a multi-institutional study evaluating the accuracy of cultures for Cutibacterium using positive control (PC) and negative control (NC) samples. The relationship between time to culture positivity and strength of culture positivity was also studied. Eleven different institutions were each sent 12 blinded samples (10 PC and 2 NC samples). The 10 PC samples included 2 sets of 5 different dilutions of a Cutibacterium isolate from a failed total shoulder arthroplasty with a probable periprosthetic infection. At each institution, the samples were handled as if they were received from the operating room. Specimen growth, time to culture positivity, and strength of culture positivity (based on semiquantitative assessment) were reported. A total of 110 PC samples and 22 NC samples were tested. One hundred percent of specimens at the 4 highest dilutions were positive for Cutibacterium. At the lowest dilution, 91% of samples showed positive findings. Cutibacterium grew in 14% of NC samples. Cutibacterium grew in PC samples at an average of 4.0±1.3 days, and all of these samples showed growth within 7 days. The time to positivity was significantly shorter (P<.001) and the strength of positivity was significantly higher (P<.001) in true-positive cultures compared with false-positive cultures. This multi-institutional study suggests that different institutions may report highly consistent rates of culture positivity for revision shoulder arthroplasty samples with higher bacterial loads. In contrast, with lower bacterial loads, the results are somewhat less consistent. Clinicians should consider using a shorter time to positivity and a higher strength of positivity as adjuncts in determining whether a tissue culture sample is a true positive.

A Clinical Significance of Fungal Infections in Diabetic Foot Ulcers.

Background: Diabetic foot ulcers (DFUs) are the most common and serious complications in uncontrolled diabetes. Infections are predominantly polymicrobial, with aerobic Gram-positive, anerobic, and fungal infections. Early detection of fungal infection and initiation of appropriate treatment in DFUs may lead to better healing and avoid amputations. The primary objective was to find out the prevalence of DFUs getting infected with fungus and the secondary objective was to identify the appropriate methodology for the detection of the fungus in DFUs.Materials and methods: This was a cross-sectional observational study carried out in a tertiary care hospital with a sample size of 60 DFUs. Microbiological analysis was done by swab culture and deep tissue culture. Observational data were collected and the significance level was statistically analyzed.Results: In the present study, the prevalence of fungal infections in DFUs was 31.7%. Only fungal tissue was positive in 15%, the fungal swab was positive in 8.33%, and both tissue and swab were positive in 8.33%. All these patients were treated with antifungal treatment as per the culture report in addition to appropriate antimicrobial therapy.Conclusion: A fungal culture should be done in all patients with non-healing DFUs. Both fungal swab and tissue culture testing should be advocated in patients with DFUs for better mycological evaluation. The addition of antifungal medications may provide better outcomes in selected cases.

Is the Addition of Anaerobic Coverage to Perioperative Antibiotic Prophylaxis During Soft Tissue Sarcoma Resection Associated With a Reduction in the Proportion of Wound Complications?

Wound complications are common after resection of soft tissue sarcomas, with published infection rates ranging from 10% to 35%. Multiple studies have reported on the atypical flora comprising these infections, which are often polymicrobial and contain anaerobic bacteria, and recent studies have noted the high prevalence of anaerobic bacterial infections after soft tissue sarcoma resection [ 26, 35 ]. Based on this, our institution changed clinical practice to include an antibiotic with anaerobic coverage in addition to the standard first-generation cephalosporin for prophylaxis during soft tissue sarcoma resections. The current study was undertaken to evaluate whether this change was associated with a change in major wound complications, and if the change should therefore be adopted for future patients. (1) After controlling for potentially confounding variables, was the broadening of the prophylactic antibiotic spectrum to cover anaerobic bacteria associated with a lower odds of major wound complications after soft tissue sarcoma resection? (2) Was the broadening of the prophylactic antibiotic spectrum to cover anaerobic bacteria associated with a lower odds of surgical site infections with polymicrobial or anaerobic infections after soft tissue sarcoma resection? (3) What are the factors associated with major wound complications after soft tissue sarcoma resection? We retrospectively identified 623 patients who underwent soft tissue sarcoma resection at a single center between January 2008 and January 2021 using procedural terminology codes. Of these, four (0.6%) pediatric patients were excluded, as were five (0.8%) patients with atypical lipomatous tumors and two (0.3%) patients with primary bone tumors; 5% (33 of 623) who were lost to follow-up, leaving 579 for final analysis. The prophylactic antibiotic regimen given at the resection and whether a wound complication occurred were recorded. Patients received the augmented regimen based on whether they underwent resection after the change in practice in July 2018. A total of 497 patients received a standard antibiotic regimen (usually a first-generation cephalosporin), and 82 patients received an augmented regimen with anaerobic coverage (most often metronidazole). Of the 579 patients, 53% (307) were male (53% [264 of 497] in the standard regimen and 52% [43 of 82] in the augmented regimen), and the mean age was 59 ± 17 years (59 ± 17 and 60 ±17 years in the standard and augmented groups, respectively). Wound complications were defined as any of the following within 120 days of the initial resection: formal wound debridement in the operating room, other interventions such as percutaneous drain placement, readmission for intravenous antibiotics, or deep wound packing for more than 120 days from the resection. Patients were considered to have a surgical site infection if positive cultures resulted from deep tissue cultures taken intraoperatively at the time of debridement. The proportion of patients with major wound complications was 26% (150 of 579); it was 27% (136 of 497) and 17% (14 of 82) in the standard and augmented antibiotic cohorts, respectively (p = 0.049). With the numbers we had, we could not document that the addition of antibiotics with anaerobic coverage was associated with lower odds of anaerobic (4% versus 6%; p = 0.51) or polymicrobial infections (9% versus 14%; p = 0.25). Patient, tumor, and treatment (surgical, radiotherapy, and chemotherapy) variables were collected to evaluate factors associated with overall infection and anaerobic or polymicrobial infection. Patient follow-up was 120 days to capture early wound complications. A multivariable analysis was performed for all variables found to be significant in the univariate analysis. A p value < 0.05 was used as the threshold for statistical significance for all analyses. No patients were found to have an adverse reaction to the augmented regimen, including allergic reactions or Clostridioides (formerly Clostridium) difficile infection. After controlling for other potentially confounding factors such as neoadjuvant radiation, tumor size and anatomic location, as well as patient BMI, anaerobic coverage was associated with smaller odds of wound complications (OR 0.36 [95% confidence interval (CI) 0.18 to 0.68]; p = 0.003). Other factors associated with major wound complications were preoperative radiation (versus no preoperative radiation) (OR 2.66 [95% CI 1.72 to 4.15]; p < 0.001), increasing tumor size (OR 1.04 [95% CI 1.00 to 1.07]; p = 0.03), patient BMI (OR 1.07 [95% CI 1.04 to 1.11]; p < 0.001), and tumor in the distal upper extremity (versus proximal upper extremity, pelvis/groin/hip, and lower extremity) (OR 0.18 [95% CI 0.04 to 0.62]; p = 0.01). The addition of anaerobic coverage to the standard prophylactic regimen during soft tissue sarcoma resection demonstrated an association with smaller odds of major wound complications and no documented adverse reactions. Treating physicians should consider these findings but note that they are preliminary, and that further work is needed to replicate them in a more controlled study design such as a prospective trial. Level III, therapeutic study.

An Analysis of 400 Sternal Wound Reconstructions at a Single Institution: Bacterial Pathogens Vary With Time.

Sternal wound (SW) infection and dehiscence after median sternotomy from cardiac surgery remain challenging complications with high morbidity. Knowledge of common pathogen types and variance with time from cardiac surgery can simplify the choice of antibiotics while awaiting definitive culture results. Records of 505 patients undergoing SW reconstruction by the senior author from 1996 to 2018 at a high-volume cardiac surgery center were reviewed. The most common indications for reconstruction were SW infection and dehiscence. At surgery, all patients underwent removal of sternal hardware, thorough debridement, and closure with bilateral pectoralis major myocutaneous advancement flaps. Deep tissue and bone cultures were sent in nearly all cases. Patients were split into group 1 or group 2 based on timing of flap reconstruction after initial cardiac surgery: 0 to 30 days and longer than 30 days, respectively. Complete data were available for 400 SW procedures performed during this period. Group 1 included 203 patients, and group 2 had 197 patients, with a mean time to SW surgery of 16.3 and 138.1 days, respectively. Intraoperative cultures were positive in 147 of 203 (72.4%), and 122 of 197 (61.9%) patients, respectively. Forty-four patients grew polymicrobial cultures. There was a significant difference in culture positivity rates in the 2 groups (P = 0.0004). The most common bacteria cultured in group 1 was Staphylococcus epidermidis (54 of 203 vs 21 of 197; P < 0.0001), whereas methicillin-sensitive Staphylococcus aureus was most common in group 2 (15 of 203 vs 22 of 197; P = 0.23). Methicillin-resistant S. aureus was relatively common in both groups (17 of 203 vs 21 of 197; P = 0.50). Although not statistically significant, Pseudomonas, Klebsiella, and Candida were all found in a higher percentage of patients in group 2 (p = 0.11, 0.20, 0.20). Microbial species cultured in SW flap reconstruction vary over time. Staphylococcus epidermidis is the most common infectious agent in patients having reconstruction within 30 days of cardiac surgery, whereas methicillin-sensitive S. aureus is most common after 30 days. The trend toward a higher incidence of Gram-negative and fungal organisms after 30 days may indicate a need for broader initial anti-infective coverage in this patient group. Awareness of these pathogen patterns can better inform antibiotic selection while awaiting culture data.

Multifaceted Strategy Improves Outcomes of Patients Hospitalized with a Diabetic Foot Infection.

Diabetic foot infections (DFIs) are associated with major morbidity, reduced quality of life and increased mortality. Osteomyelitis is a leading cause of lower-extremity amputation in diabetic patients. We aimed to examine whether a multifaceted strategy for treating hospitalized patients with a DFI effectively influenced microbiological culture results and outcomes. A retrospective cohort-study in a 1100-bed, tertiary-care university hospital was conducted. Adult patients with a DFI admitted to the orthopedics department between 2015 and 2019 were included. During the pre-intervention period (2015-2016), one general orthopedic department was in operation. In the post-intervention period (2017-2019), a second department was created with a designated "complicated wound unit". The multifaceted strategy included revising local guidelines for DFI culturing emphasizing bone cultures, correct sample handling, and adjusting antibiotic treatment to culture results. Additionally, a weekly multidisciplinary-team grand round was instigated and post-discharge outpatient follow-up was scheduled. 652 patients with DFIs were included; 101 during the pre-intervention period and 551 during the post-intervention period. Compared to the pre-intervention, during the post-intervention period mainly bone or deep-tissue cultures were performed (9.7% vs. 98.2%, P < 0.001). Bacteriology cultures in the pre-intervention versus post-intervention period revealed: among staphylococcus isolates, fewer methicillin-resistant Staphylococcus aureus detected (20.4% vs. 9.8%, P = 0.010); within Enterobacteriaceae isolates, fewer extended-spectrum β-lactamase producing bacteria detected (51.6% vs. 23.6%, P < 0.001); a decrease in Pseudomonas aeruginosa isolates (28% vs. 10.6%, P < 0.001) and an increase in anaerobic bacterial isolates (0 vs. 11.1%, P < 0.001). On multivariate regression, the post-intervention period (ie multifaceted strategy) was a protective measure against readmissions (P = 0.007 OR 0.50 95% CI 0.30-0.82). We conclude that our interventive multifaceted strategy led to accurate bacterial diagnosis, de-escalation of antibiotic treatment and readmission reduction.