Regional antibiotic delivery for sternal wound infection prophylaxis a systematic review and meta-analysis of randomized controlled trials.

Despite evidence suggesting the benefit of prophylactic regional antibiotic delivery (RAD) to sternal edges during cardiac surgery, it is seldom performed in clinical practice. The value of topical vancomycin and gentamicin for sternal wound infections (SWI) prophylaxis was further questioned by recent studies including randomized controlled trials (RCTs). The aim of this systematic review and meta-analysis was to comprehensively assess the safety and effectiveness of RAD to reduce the risk of SWI.We screened multiple databases for RCTs assessing the effectiveness of RAD (vancomycin, gentamicin) in SWI prophylaxis. Random effects meta-analysis was performed. The primary endpoint was any SWI; other wound complications were also analysed. Odds Ratios served as the primary statistical analyses. Trial sequential analysis (TSA) was performed.Thirteen RCTs (N = 7,719 patients) were included. The odds of any SWI were significantly reduced by over 50% with any RAD: OR (95%CIs): 0.49 (0.35-0.68); p < 0.001 and consistently reduced in vancomycin (0.34 [0.18-0.64]; p < 0.001) and gentamicin (0.58 [0.39-0.86]; p = 0.007) groups (psubgroup = 0.15). Similarly, RAD reduced the odds of SWI in diabetic and non-diabetic patients (0.46 [0.32-0.65]; p < 0.001 and 0.60 [0.44-0.83]; p = 0.002 respectively). Cumulative Z-curve passed the TSA-adjusted boundary for SWIs suggesting adequate power has been met and no further trials are needed. RAD significantly reduced deep (0.60 [0.43-0.83]; p = 0.003) and superficial SWIs (0.54 [0.32-0.91]; p = 0.02). No differences were seen in mediastinitis and mortality, however, limited number of studies assessed these endpoints. There was no evidence of systemic toxicity, sternal dehiscence and resistant strains emergence. Both vancomycin and gentamicin reduced the odds of cultures outside their respective serum concentrations' activity: vancomycin against gram-negative strains: 0.20 (0.01-4.18) and gentamicin against gram-positive strains: 0.42 (0.28-0.62); P < 0.001. Regional antibiotic delivery is safe and effectively reduces the risk of SWI in cardiac surgery patients.

Recurrent sternal wound infection caused by Gordonia bronchialis after open heart surgery.

Gordonia bronchialis is an aerobic gram-positive bacilli and also weakly acid fast. It requires a long incubation time and extensive biochemical reactions for identification. Therefore, use of broad-range polymerase chain reaction (PCR) for amplification of genes such as 16S rRNA or hsp65 followed by sequencing or advanced techniques like MALDI-TOF MS is needed for identification. Here, we present a case of persistent sternal wound infection following open heart surgery, caused by G. bronchialis in a 58 years old male, identified using MALDI-TOF MS-based system. The patient improved with oral Cefpodoxime 200 mg BD for four weeks.

The illusion of a chest wall tumor: a case-report of sternal tuberculosis.

The incidence rate of tuberculosis in developed countries is low. The most common presentation of this disease is its pulmonary form but with the increasing use of immunosuppressive drugs, extra-pulmonary tuberculosis is re-emerging. Nevertheless, sternal bone involvement is uncommon. We report the case of an eighty-three-year-old man who presented a painful sternal mass which progressed towards cutaneous ulceration. The first diagnostic hypothesis was neoplasia. The pathological and microbiological diagnosis of tuberculosis was achieved after surgical biopsy. The patient received treatment against tuberculosis for nine months enabling recovery without surgery. This case illustrates the importance of having a diagnosis prior to any kind of treatment facing any voluminous parietal thoracic lesions.  This diagnosis is made possible by surgical samples and interdisciplinary teamwork. This case underlines that tuberculosis remains a differential diagnosis that must be evoked in case of unusual bone mass.

Risk Factors Associated with an Increased Risk of Deep Sternal Wound Infections in Patients After Coronary Artery Bypass Grafting and Heart Defect Surgery.

BACKGROUND: Despite improvements over time with regard to morbidity, mortality, and long-term survival, deep sternal wound infection (DSWI) continues to be a major complication after open-heart surgery. This is why it is important to identify possible risk factors for postoperative development of DSWI in patients undergoing coronary artery bypass grafting and valve replacement. The aim of this study was to identify the risk factors for postoperative development of deep sternal wound infection in patients after coronary artery bypass grafting and heart defect surgery at the Department of Thoracic, Cardiac, and Vascular Surgery of the Hospital of Lithuanian University of Health Sciences. METHODS: This retrospective study analyzed 201 patients, who underwent coronary artery bypass grafting and heart defect surgery between January 2017 and December 2018. The case group contained 45 patients, who had to be reoperated because of deep sternal wound infection, and the control group consisted of 156 randomly selected patients. For descriptive statistics, we used means, median values, ranges, standard deviations, and 95% confidence intervals, where appropriate. Categorical data were analyzed using the chi-square or Fisher's exact test. Student T-test and Mann-Whitney used to compare numerical variables. Logistic regression model adjusting for age and gender was used to compare the risk of infection. A P-value of < 0.05 was considered to be statistically significant. SPSS 26.0 was used for calculations. RESULTS: Logistic regression analysis revealed that independent risk factors for sternal wound infection were high BMI (odds ratio [OR] 1.15, CI 1.06-1.24), preoperative CRP (OR 1.08, CI 1.01-1.16), long duration of cardiopulmonary bypass (OR 1.02, CI 1.01-1.03), intraoperative anemia (OR 0.97, CI 0.95-0.99), and postoperative CRP concentration (OR 1.10; CI 1.05-1.16). CONCLUSIONS: Preoperative assessment to identify obese individuals as being at risk and techniques to minimize the duration of surgery and intraoperative blood loss may help reduce postoperative deep sternal wound infections.

Does routine topical antimicrobial administration prevent sternal wound infection after cardiac surgery?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'Does routine topical antimicrobial administration prevent sternal wound infection (SWI) after cardiac surgery? Altogether >238 papers were found using the reported search, of which 11 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Several different antimicrobial agents, dosages and application protocols were found in the literature. Regarding topical vancomycin use, a meta-analysis by Kowalewski et al. demonstrated a 76% risk reduction in any SWI. Collagen-gentamicin sponge application was associated with a 38% risk reduction in SWI in another meta-analysis by Kowalewski et al., which included 4 randomized control trials and >23 000 patients. Lower evidence observational studies found benefit in the use of different regimes, including: combination of vancomycin paste and subcutaneous gentamycin; combined cefazoline and gentamicin spray; isolated cefazolin; bacitracin ointment; and rifampicin irrigation. We conclude that, in light of the body of evidence available, topical antibiotic application prevents SWI, including both superficial and deep SWI. The strongest evidence, derived from 2 meta-analyses, is related to the use of gentamicin-collagen sponges and topical vancomycin. Heterogeneity throughout studies regarding antibiotic agents, dosages, application protocols and SWI definition makes providing general recommendations challenging.

[Sternal tuberculosis: an unusual location of tuberculosis]. / Tuberculose sternale : une localisation inhabituelle de la tuberculose.

INTRODUCTION: Osteo-articular tuberculosis mainly affects the spine. Sternal localization is rare. CASE REPORT: A 43-year-old man, HIV negative and with a history of tuberculous pleurisy, was seen in a pulmonology consultation for abscesses of the chest wall. The thoracic CT scan revealed multiple antesternal and retrosternal abscesses as well as bone lesions in the sternum, ribs and vertebrae. The diagnosis of sternal tuberculosis was made by microscopy and Xpert MTB/RIF test performed on pus from the abscesses. The progress under anti-tuberculous treatment was favourable. CONCLUSION: Sternal involvement with tuberculosis is uncommon and rarely detected. The problem is mainly diagnostic. Its therapy is based on anti-tuberculous treatment.

[Negative pressure wound therapy for deep sternal wound infections: microbiological characteristics and antibiotic resistance]. / Vliyanie vakuum-assistirovannoi povyazki na lechenie glubokoi infektsii grudiny: bakteriologicheskii analiz i antibiotikorezistentnost'.

OBJECTIVE: To evaluate bacterial flora in patients with deep sternal wound infection and the effect of negative pressure wound therapy on eradication of the pathogen. MATERIAL AND METHODS: There were 102 patients with deep wound infection after cardiac surgery. Mean age was 66.9±9.9 years. Diabetes mellitus was detected in 21 (20.5%) cases, chronic obstructive pulmonary disease - in 15 (14.7%). Wound debridement via daily dressings was performed in 64 patients; vacuum-assisted dressings were applied in 38 patients. Bacteriological analysis of discharge was carried out every week.Results. Mixed infection was observed in 38 (37.3%) patients. S.aureus was the most common pathogen (n=51, 50%), Gram negative bacteria were found in 36 (35.3%) patients. Negative pressure wound therapy ensured eradication of S.aureus within 3 weeks while dressings were associated with only 40% decrease of the incidence of positive analyses (p<0.05). Effectiveness of the method was not obtained for Gram negative bacteria. CONCLUSION: Negative pressure wound therapy accelerates eradication of Gram positive pathogens but does not affect eradication of Gram negative microbes.

The value of 18 F-FDG PET/CT in diagnosing and localising deep sternal wound infection to guide surgical debridement.

Deep sternal wound infection (DSWI) is a severe complication in patients after open heart surgery (OHS). But there is a lack of appropriate imaging tool to detect the infection sites, which may lead to incomplete debridement. The present study aims to investigate the value of 18 F-fluorodeoxyglucose positron emission tomography/computed tomography (18 F-FDG PET/CT) in comparison with CT scan in diagnosing and localising DSWI. A total of 102 patients with DSWI after OHS were retrospectively collected from January 2012 to December 2017 in our hospital. All the patients had surgical debridements for DSWI with pretreatment imaging of either 18 F-FDG PET/CT or CT scan. The sensitivity, specificity, and accuracy of localising infection sites were compared between PET/CT and CT groups, with surgical, microbiological, and histopathological findings as the gold standard. The length of hospital stays and the rate of recurrence were also compared. Ten patients in the PET/CT group had a follow-up PET/CT scan after debridement, and the correlations between the changes of PET/CT findings and surgical outcomes were analysed. 18 F-FDG PET/CT is more accurate than CT in diagnosing and localising DSWI after OHS, which leads to a more successful surgical debridement with a lower rate of recurrence and a shorter length of hospital stay. In addition, follow-up PET/CT after debridement could evaluate the treatment effect.

Impact of microbial findings on plastic reconstructive surgery outcomes in patients with deep sternal wound infection after cardiac surgery.

Deep sternal wound infection (DSWI) is a life threatening complication after cardiac surgery. In severe cases, flaps are needed to cover the wound. However, it is controversial if an aseptic environment is necessary at the time of wound closure. This is a retrospective study of 73 patients with DSWI treated by debridement and local or free flap from June 2008 until December 2017. The influence of positive microbiological findings at the time of plastic reconstructive surgery on reoperation rate and length of in-hospital stay was analyzed. Microbiological exams revealed positive results in 47 (64.4%) and no results in 26 patients. Reoperation had to be performed in 21.3% (positive cultures) versus 15.4% (p = .54), mean in hospital stay was 24.1 days (positive cultures) versus 21.8 days (p = .39) and in-hospital mortality was 6.4% (positive cultures) versus 7.7% (p = .83). Positive microbial findings at the time of plastic reconstructive surgery in patients with DSWI are not associated with a higher reoperation or mortality rate or a longer in-hospital stay. Repeated debridement and vacuum-assisted therapy to achieve negative microbial results might not be necessary in the treatment of these patients.Key messagesPositive microbial findings at the time of plastic reconstructive surgery in patients with deep sternal wound infection seems not to be associated with a higher reoperation or mortality rate or a longer in-hospital stay.The influence of positive microbiological findings at the time of plastic reconstructive surgery on reoperation rate and length of in-hospital stay was analyzed in 73 patients with deep sternal wound infection.Microbiological exams revealed positive results in 47 (64.4%) and no results in 26 patients. Reoperation had to be performed in 21.3% (positive cultures) versus 15.4% (p = .54), mean in hospital stay was 24.1 days (positive cultures) versus 21.8 days (p = .39) and in-hospital mortality was 6.4% (positive cultures) versus 7.7% (p = .83).

Preoperative risk stratification of deep sternal wound infection after coronary surgery.

OBJECTIVE: To develop a risk score for deep sternal wound infection (DSWI) after isolated coronary artery bypass grafting (CABG). DESIGN: Multicenter, prospective study. SETTING: Tertiary-care referral hospitals. PARTICIPANTS: The study included 7,352 patients from the European multicenter coronary artery bypass grafting (E-CABG) registry. INTERVENTION: Isolated CABG. METHODS: An additive risk score (the E-CABG DSWI score) was estimated from the derivation data set (66.7% of patients), and its performance was assessed in the validation data set (33.3% of patients). RESULTS: DSWI occurred in 181 (2.5%) patients and increased 1-year mortality (adjusted hazard ratio, 4.275; 95% confidence interval [CI], 2.804-6.517). Female gender (odds ratio [OR], 1.804; 95% CI, 1.161-2.802), body mass index ≥30 kg/m2 (OR, 1.729; 95% CI, 1.166-2.562), glomerular filtration rate <45 mL/min/1.73 m2 (OR, 2.410; 95% CI, 1.413-4.111), diabetes (OR, 1.741; 95% CI, 1.178-2.573), pulmonary disease (OR, 1.935; 95% CI, 1.178-3.180), atrial fibrillation (OR, 1.854; 95% CI, 1.096-3.138), critical preoperative state (OR, 2.196; 95% CI, 1.209-3.891), and bilateral internal mammary artery grafting (OR, 2.088; 95% CI, 1.422-3.066) were predictors of DSWI (derivation data set). An additive risk score was calculated by assigning 1 point to each of these independent risk factors for DSWI. In the validation data set, the rate of DSWI increased along with the E-CABG DSWI scores (score of 0, 1.0%; score of 1, 1.8%; score of 2, 2.2%; score of 3, 6.9%; score ≥4: 12.1%; P < .0001). Net reclassification improvement, integrated discrimination improvement, and decision curve analysis showed that the E-CABG DSWI score performed better than other risk scores. CONCLUSIONS: DSWI is associated with poor outcome after CABG, and its risk can be stratified using the E-CABG DSWI score. TRIAL REGISTRATION: clinicaltrials.gov identifier: NCT02319083.

Safety of a 2-Day Antibiotic Regimen After Delayed Chest Closure Post Pediatric Cardiac Surgery.

BACKGROUND: There is no consensus for the length of prophylactic antibiotics after delayed chest closure (DCC) postcardiac surgery in pediatrics. In September 2014, our institution's pediatric cardiac intensive care unit changed the policy on length of prophylactic antibiotics after DCC from 5 days (control) to 2 days (study group). The objective of the study was to determine whether a 2-day course of antibiotics is as effective as a 5-day course in preventing blood stream and sternal wound infections in pediatric DCC. METHODS: Retrospective and prospective study. Primary end points included incidence of sternal wound infections and positive sternal imaging for infection. Surrogate markers of infection were collected at 4 time points. RESULTS: During the study period, 139 patients had DCC postcardiac surgery of which 110 patients were included for analysis, 54 patients in the control and 56 in the study group. There was no difference in total number of positive wound cultures/chest computed tomography (CT) findings (4/54 [7.5%] control vs 5/56 [8.9%] study group, P = .3), positive blood cultures (P = .586), median postsurgical length of stay (P = .4), or readmissions within 30 days postsurgery (P = .6). All secondary end points were similar in both groups except peak heart rate between weeks 2 and 4 (P = .041). CONCLUSION: Two days of prophylactic antibiotics is not inferior to 5 days of prophylactic antibiotics after DCC following pediatric cardiac surgery.

Vacuum-Assisted Closure for the Treatment of Deep Sternal Wound Infection After Pediatric Cardiac Surgery.

OBJECTIVES: Vacuum-assisted closure is being increasingly used to treat deep sternal wound infection following cardiac surgery, but most of the data refer to adults. This study investigated the safety and efficacy of vacuum-assisted closure in pediatric patients. DESIGN: Retrospective file review. SETTING: Tertiary pediatric medical center. PATIENTS: All children with deep sternal wound infection treated with vacuum-assisted closure in 2003-2016. INTERVENTIONS: Epidemiological, clinical, and microbiological data were collected from the medical records. MEASUREMENTS AND MAIN RESULTS: The cohort included 50 patients (0.9% of cardiac patients operated during the study period) of median age 6.5 months (interquartile range, 2-12.75 mo; range, 1 wk to 14 yr) and median weight 5.1 kg (interquartile range, 4-9.75 kg). The most frequent heart defects were tetralogy of Fallot (22%) and ventricular septal defect (20%); 38% of patients had cyanotic heart disease. Deep sternal wound infections appeared a median of 10 days postoperatively (interquartile range, 7-14 d; range 3-100 d). Vacuum-assisted closure was applied a median of 13 days postoperatively (interquartile range, 10-18.5 d; range, 5-103 d) for a median duration of 10 days (interquartile range, 7-13.25 d; range, 1-21 d). Wound cultures were positive in 48 patients (96%); most isolates were Gram-positive (76%). The main bacterial pathogen was methicillin-susceptible Staphylococcus aureus (61%). Most patients were treated with cloxacillin for a median of 38 days (interquartile range, 28-42 d; range, 9-189 d). There were no statistically significant differences in clinical or treatment characteristics between bacteremic (56%) and nonbacteremic patients. Compared with older patients, infants less than 3 months old (36%) had a significantly longer hospitalization time (41 vs 25 d; p = 0.001) and higher Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery Mortality Category (3 vs 2; p = 0.003). All cases except one (contact dermatitis) were uneventful. In 10 patients, wounds were closed surgically after vacuum-assisted closure. Two patients required a pectoralis flap, both treated before 2005. One of the two deaths was infection-related. CONCLUSIONS: Vacuum-assisted closure is a feasible treatment option of deep sternal wound infection after pediatric cardiac surgery and was not associated with independent morbidity.

Isolated primary cold abscess of the sternum: a case report.

BACKGROUND: Musculoskeletal tuberculosis forms 10-25% of extrapulmonary tuberculosis which mainly involves the spine or weight-bearing joints. Tuberculous involvement of the sternum is a rare clinical entity even in countries where tuberculosis has high prevalence. Primary tuberculous sternal osteomyelitis accounts for approximately 0.3% of all types of tubercular osteomyelitis and the probable source appears to be extension from paratracheal or hilar lymph nodes. Despite tuberculosis being a common disease in endemic countries and worldwide, a thorough literature search of the PubMed database for keywords "primary tuberculosis of sternum" and "primary tuberculous osteomyelitis of sternum" yielded 30 and 22 articles, respectively. CASE PRESENTATION: We present an unusual case of a large dumb-bell-shaped cold abscess arising due to infection of the sternum. A 23-year-old immunocompetent Asian woman presented with a gradually progressing painless swelling on anterior chest wall for the last 5 months. She had a large visible swelling on anterior chest wall which was 12.5 cm in diameter, soft, non-tender, temperature was not raised, and fluctuant. Magnetic resonance imaging showed a large dumb-bell-shaped hyperintense collection in upper anterior chest wall with marrow edema and cortical irregularity in left side of manubrium. Pus was positive for nucleic acid testing (cartridge-based nucleic acid amplification test) for Mycobacterium tuberculosis and later culture was also positive. She was started on anti-tubercular therapy and aspirated twice. Currently, she has completed 6 months of therapy and the swelling has now disappeared. DISCUSSION: Swelling, pain localized to sternum, or ulceration of the skin with discharging sinus along with or without constitutional symptoms are the usual presentation. A high element of suspicion is needed for early diagnosis and treatment to prevent its complications. Sternal mycobacterial infections are categorized as primary, secondary, and/or acquired postoperatively. Although radiological investigations aid in diagnosis, the diagnosis is established by positive culture or histopathological examination. Anti-tubercular therapy is the mainstay of treatment with standard four-drug regimen for 6-9 months. Surgical drainage of the abscess should be considered only if it does not resolve by aspiration and anti-tubercular therapy.

Sternal osteomyelitis by Gordonia Bronchialis in an immunocompetent patient after open heart surgery.

Gordonia is a catalase-positive, aerobic, nocardioform, Gram-positive staining actinomycete that also shows weak acid-fast staining. Several Gordonia species are commonly found in the soil. The bacterium has been isolated from the saliva of domesticated/wild dogs as well. In hospitalized patients, most commonly it is found in the setting of intravascular catheter-related infections. However, recent reports show that it is being increasingly isolated from sternal wounds, skin/neoplastic specimens and from pleural effusions. Gordonia shares many common characteristics with Rhodococcus and Nocardia. Ergo, it is commonly misrecognized as Nocardia or Rhodococcus. Since this pathogen requires comprehensive morphological and biochemical testing, it is often difficult and cumbersome to isolate the species. Broad-range Polymerase Chain Reaction (PCR) and sequencing with genes like 16S rRNA or hsp65 are used to correctly identify the species. Identification is essential for choosing and narrowing the right antimicrobial agent. Herein, we report our experience with a patient who presented with sternal osteomyelitis after infection with this elusive bug.

Clinical experience with dalbavancin for the treatment of deep sternal wound infection.

OBJECTIVES: Deep sternal wound infection (DSWI) is a complication of major heart surgery with high morbidity as well as prolonged antimicrobial treatment and hospital length of stay (LoS). Dalbavancin is a new lipoglycopeptide antibiotic active against Gram-positive micro-organisms, including methicillin-resistant Staphylococcus aureus (MRSA), with a long half-life. This small case series assessed the feasibility of dalbavancin for the treatment of DSWI. METHODS: This was retrospective, observational, cohort study of patients treated with dalbavancin for DSWI over a 2-year period (March 2016 to April 2018) in two cardiac surgery departments in Italy. All patients with DSWI underwent surgical accurate debridement. Dalbavancin was administered during the hospital stay or in an outpatient facility. RESULTS: Among 15 patients enrolled in the study, MRSA was isolated in 7 (47%), methicillin-resistant Staphylococcus epidermidis in 6 (40%) and other coagulase-negative staphylococci in 2 (13%). Dalbavancin was administered by two infusions in 9 patients (60%), whereas 5 patients (33%) received a median of four doses. Fourteen patients received a first dose of 1000mg followed by 500mg, whereas one patient received two doses of 1500mg each. All patients were defined as clinically cured. The median hospital LoS was 13 days (interquartile range, 8-18 days). At 6 months after discharge, 14 patients (93%) showed no relapse of DSWI, whereas 1 patient recurred with a diagnosis of DSWI caused by another pathogen (Candida sp.). CONCLUSION: Dalbavancin may be an alternative option for DSWI caused by Gram-positive bacteria when first-line treatments are contraindicated or as salvage treatment.