Vaccine Effectiveness against SARS-CoV-2 Infection during the Circulation of Alpha, Delta, or Omicron Variants: A Retrospective Cohort Study in a Tertiary Hospital in Serbia.

The COVID-19 pandemic prompted rapid vaccine development and deployment worldwide. Despite widespread vaccination efforts, understanding the effectiveness of vaccines in hospitalized patients remains a critical concern. This retrospective cohort study, conducted at a tertiary healthcare centre in Serbia, tracked patients hospitalized during different waves of COVID-19 variants-Alpha, Delta, and Omicron. Data collection included demographics, comorbidities, symptoms, and vaccination status. Among 3593 patients, those with prior exposure to COVID-19 cases or hospital treatment showed higher positivity rates. Symptom prevalence varied across waves, with coughs persisting. Patients without chronic diseases were more frequent among those testing negative. Vaccine effectiveness varied, with Sinopharm demonstrating a 45.6% effectiveness initially and Pfizer-BioNTech showing an effectiveness of up to 74.8% within 0-84 days after the second dose. Mixed-dose strategies, notably Sinopharm as a primary dose followed by a Pfizer-BioNTech booster, suggested increased protection. Despite substantial vaccination availability, a significant portion of hospitalized patients remained unvaccinated. This study underscores the dynamic nature of vaccine effectiveness and advocates for booster strategies to address evolving challenges in combating COVID-19, particularly in hospitalized patients.

Epidemiological Predictors of Positive SARS-CoV-2 Polymerase Chain Reaction Test in Three Cohorts: Hospitalized Patients, Healthcare Workers, and Military Population, Serbia, 2020.

(1) Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its resulting coronavirus disease 2019 (COVID-19) has caused a fast-moving pandemic. Diagnostic testing, aimed to identify patients infected with SARS-CoV-2, plays a key role in controlling the COVID-19 pandemic in different populations. (2) Methods: This retrospective cohort study aimed to investigate predictors associated with positive polymerase chain reaction (PCR) SARS-CoV-2 test results in hospitalized patients, healthcare workers (HCWs), and military personnel (MP) during 2020, before the widespread availability of COVID-19 vaccines. Persons with a positive test result were compared with persons with a negative test result in three cohorts during the study period. (3) Results: A total of 6912 respondents were tested, and 1334 (19.3%) of them had positive PCR SARS-CoV-2 test results. Contact with a known COVID-19 case within 14 days (p < 0.001; OR: 1.48; 95% CI: 1.25-1.76), fever (p < 0.001; OR: 3.66; 95% CI: 3.04-4.41), cough (p < 0.001; OR: 1.91; 95% CI: 1.59-2.30), headache (p = 0.028; OR: 1.24; 95% CI: 1.02-1.50), and myalgia/arthralgia (p < 0.001; OR: 1.99; 95% CI: 1.65-2.42) were independently associated with positive PCR SARS-CoV-2 test results in the cohort of MP. Furthermore, fever (p < 0.001; OR: 2.75; 95% CI: 1.83-4.13), cough (p < 0.001; OR: 2.04; 95% CI: 1.32-3.13), headache (p = 0.008; OR: 1.76; 95% CI: 1.15-2.68), and myalgia/arthralgia (p = 0.039; OR: 1.58; 95% CI: 1.02-2.45) were independently associated with positive PCR SARS-CoV-2 test results in the cohort of HCWs. Moreover, independent predictors of positive PCR SARS-CoV-2 test results in hospitalized patients were contact with a known COVID-19 case within 14 days (p < 0.001; OR: 2.56; 95% CI: 1.71-3.83), fever (p < 0.001; OR: 1.89; 95% CI: 1.38-2.59), pneumonia (p = 0.041; OR: 1.45; 95% CI: 1.01-2.09), and neurological diseases (p = 0.009; OR: 0.375; 95% CI: 0.18-0.78). (4) Conclusions: According to data gathered from cohorts of hospitalized patients, HCWs, and MP, before the widespread availability of COVID-19 vaccines in Serbia, we can conclude that predictors of positive PCR SARS-CoV-2 test results in MP and HCWs were similar. Accurate estimates of COVID-19 in different population groups are important for health authorities.

An assessment of burden of hospital-acquired pneumonia among abdominal surgical patients in tertiary university hospital in Serbia: A matched nested case-control study.

Background: In the population of abdominal surgical patients hospital-acquired pneumonia (HAP) significantly increases morbidity and mortality. Patients and methods: Through regular hospital surveillance of patients who received abdominal operations, we identified postoperative HAP from 2007 to 2019. In an initial nested case-control study, every surgical patient with HAP was compared with three control patients without HAP. Control patients were matched to the cases by age, gender, the American Society of Anesthesiologists score, and type of surgical operation. Also, the patients with HAP, who died were compared with those who survived. Results: Multivariate logistic regression analysis (MLRA) revealed that other postoperative infections, length of intensive care unit stay, use of H2RA, use of PPI/ H2RA, multiple transfusion, and use of vancomycin in surgical prophylaxis were independent RFs for occurrence of HAP. Also, MLRA identified that age, lenght of hospital stay, use of mechanical ventilation and ceftriaxone in HAP therapy were indepedenttly associated with poor outcome of HAP. All Acinetobacter baumannii isolates were resistant to aminoglycoside antimicrobial agents and showed carbapenem resistance. The most frequently used antibiotics in patients with HAP and without HAP were vancomycin and metronidazole, respectively. Conclusion: Our study provided an insight into the burden of HAP in abdominal surgical patients, and highlighted several priority areas and targets for quality improvement.

Association between Antibiotic Use and Hospital-Onset Clostridioides difficile Infection in University Tertiary Hospital in Serbia, 2011-2021: An Ecological Analysis.

This ecological study is the largest to date examining the association between rates of antibiotic use (AU) and hospital-onset (HO) Clostridioides difficile infection (CDI) in a tertiary university hospital in Serbia. There was no clear trend in the incidence of HO-CDI over time. Total utilization of antibacterials for systemic use increased from 38.57 DDD/100 bed-days (BD) in 2011 to 56.39 DDD/100 BD in 2021. The most commonly used antibiotics were third-generation cephalosporins, especially ceftriaxone, with maximum consumption in 2021 (19.14 DDD/100 BD). The share of the Access group in the total utilization of antibiotics ranged from 29.95% to 42.96% during the observed period. The utilization of the Reserve group of antibiotics indicated a statistically significant increasing trend (p = 0.034). A statistically significant difference in the consumption of medium-risk antibiotics from 2011 to 2021 was shown for penicillins and a combination of sulfamethoxazole and trimethoprim. The consumption of cefotaxime showed a statistically significant negative association with the rate of HO-CDI (r = -0.647; p = 0.031). Ampicillin and the combination of amoxicilline with clavulanic acid have shown a negative statistically significant correlation with the ID of HO-CDI (r = -0.773 and r = -0.821, respectively). Moreover, there was a statistically significant negative correlation between consumption of "medium-risk antibiotics" and the rate of HO-CDI (r = -0.677). The next challenging step for the hospital multidisciplinary team for antimicrobials is to modify the antibiotic list according to the Access, Watch, and Reserve classification, in such a way that at least 60% of the AU should be from the Access group, according to the World Health Organization recommendation.

Predominance of t355/ST152/SCCmec V clonal type among PVL-positive MRSA isolates in a tertiary care hospital in Belgrade, Serbia.

Epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) is continually changing. Frequency of genotypes typical for community-associated MRSA (CA-MRSA) is increasing in hospitals, as well as resistance to antimicrobial agents. Moreover, different clones predominate in different geographic regions, and temporal shifts occur in the predominant clonal type. The aim of this study was to estimate the prevalence of MRSA, CA-MRSA and PVL-positive MRSA isolates from patients hospitalised in the Military Medical Academy (MMA) and from outpatients, and to perform genotyping of PVL-positive MRSA isolates. MRSA isolates were obtained by standard microbiological techniques. PVL-positive MRSA were detected by single PCR. Determination of SCCmec types in MRSA isolates was done using multiplex PCR and genotyping of PVL-positive MRSA by PFGE, MLST and spa typing. The prevalence of MRSA among S. aureus isolates from different clinical specimens was 43.4%. In outpatients the prevalence of MRSA was 3.2%. SCCmec types specific for CA-MRSA were found in 26% of MRSA isolates from hospitalised patients. In groups, hospitalised patients and outpatients, the prevalence of PVL-positive MRSA isolates was 4%, and all of them harboured SCCmec type V genetic element. PFGE revealed minor differences between four groups of PVL-positive MRSA isolates, but all of them belonged to ST152, and all except one were of the t355 spa type. High prevalence of MRSA and CA-MRSA in MMA, especially the presence of PVL-positive CA-MRSA, represent a serious health threat for patients. Genotype t355/ST152/SCCmec V is the dominant MRSA clone among PVL-positive CA-MRSA.

Outcomes of Clostridioides difficile infection in adult cancer and non-cancer patients hospitalised in a tertiary hospital: a prospective cohort study.

BACKGROUND: Clostridioides difficile infection (CDI) is one of the most common healthcare-associated (HA) infections. Cancer patients, particularly haemato-oncological patients, have an increased risk for CDI due to more risk factors compared with non-cancer patients. The aim of this study was to investigate differences in outcomes associated with HA CDI in patients with solid and haematological malignancies compared with patients with no underlying malignant disease in a tertiary healthcare centre in Serbia. METHODS: A prospective cohort study was conducted including adult patients diagnosed with an initial episode of HA CDI. Their demographic and clinical characteristics associated with risk factors for CDI were documented. Outcomes such as all-cause 30-day mortality, cure of infection, diarrhoea relaps and recurrence of disease were followed. Patients were assigned to cancer and non-cancer groups. Within the cancer group, patients were divided into the solid tumour subgroup and haematological malignancy subgroup. RESULTS: During a 7-year period, HA CDI was observed in 28 (5.1%) patients with haematological malignancy, 101 (18.3%) patients with solid tumours and 424 (76.7%) non-cancer patients. Older age (OR 1.04, 95% CI 1.02 to 1.07, p<0.001), admission to the intensive care unit (ICU) (OR 2.61, 95% CI 1.37 to 4.95, p=0.003), mechanical ventilation (OR 5.19, 95% CI 2.78 to 9.71, p<0.001) and use of antibiotics prior to CDI (OR 1.04, 95% CI 1.02 to 1.06, p=0.02) were associated with increased mortality. Compared with patients with solid tumours, patients with haematological malignancy were younger (65 vs 57 years, p=0.015), did not require ICU admission (25.0% vs 0%) or mechanical ventilation (8.9% vs 0%) and were treated longer with antibiotics prior to CDI (14 vs 24 days, p=0.002). CONCLUSIONS: Patients with haematological malignancy were exposed to different risk factors for CDI associated with mortality compared with patients with solid tumours and non-cancer patients. Older age, ICU stay and mechanical ventilation, but not presence or type of cancer, predicted the all-cause 30-day mortality.

Microbiology of Healthcare-Associated Infections: Results of a Fourth National Point Prevalence Survey in Serbia.

Millions of patients acquire healthcare-associated infections (HAIs) every year, putting them at risk for serious complications and prolonged hospitalization. Point prevalence surveys (PPS), guided by the European Centre for Disease Prevention and Control framework, are one of the primary methods by which countries in the European Union conduct surveillance of HAIs. Serbia, though not in the EU, implemented this approach in its national PPS. The microbiological and antimicrobial resistance (AMR) analyses comprised patients in 61 out of 65 hospitals included in the fourth PPS conducted in November 2017. A total of 515/12,380 (4.2%) of the adult patients included in the PPS had at least one HAI, with intensive care units carrying the highest prevalence of 15.9%. Urinary tract and surgical site infections were the most frequently identified types of HAIs (23.9% and 23.0%, respectively). Enterobacterales comprised almost half (47.0%) of all causative agents, most notably Klebsiella spp. (16.7%). AMR was very high for most pathogens-80.5% of nonfermentative Gram-negative bacilli were resistant to carbapenems whereas 62.9% of Enterobacterales were resistant to third generation cephalosporins. The calculated AMR index of 61% is one of the highest in Europe. Further efforts are needed to reduce the burden of HAIs in Serbia that carry very high resistance rates to antibiotics currently used in clinical practice.

Emergence of NDM-1 metallo-ß-lactamase in Pseudomonas aeruginosa clinical isolates from Serbia.

This work reports, for the first time, the presence of New Delhi metallo-ß-lactamase 1 (NDM-1) in Pseudomonas aeruginosa. Moreover, this is the first report of the NDM-1 presence in the Balkan region. Cosmid gene libraries of carbapenem-nonsusceptible Pseudomonas aeruginosa clinical isolates MMA83 and MMA533 were screened for the presence of metallo-ß-lactamases. Accordingly, both MMA83 and MMA533 carried the bla(NDM-1) gene. Pulsed-field gel electrophoresis (PFGE) analysis indicated that strains MMA83 and MMA533 belonged to different clonal groups. Five additional isolates from different patients clonally related to either MMA83 or MMA533 were found to be NDM-1 positive.

A nationwide assessment of the burden of healthcare-associated infections and antimicrobial use among surgical patients: results from Serbian point prevalence survey, 2017.

BACKGROUND: As the only non-European Union (EU) country, Serbia participated in a second point prevalence survey of healthcare-associated infections (HAIs) and antimicrobial use (AMU) organized by the European Centre for Disease Prevention and Control (ECDC) in the EU countries. Here, we aimed to estimate the prevalence of HAI and AMU in patients who had recently undergone a surgery and to compare risk profile, HAI rates, and AMU among surgical patients and non-surgical patients. METHODS: A national PPS was performed in 65 Serbian acute-care hospitals, in November 2017. In this paper, the data of 61 hospitals for adult acute-care were analyzed. To ensure the comparability of study design we used the Serbian translation of ECDC case definitions and ECDC PPS protocol. The trained infection control staff, led by a hospital coordinator, reviewed medical records to identify HAI active at the time of the survey and AMU. Only inpatients admitted to the ward before 8 a.m. on the day if the survey were included. RESULTS: A total of 12,478 patients from 61 hospitals for adult acute-care were eligible for inclusion in this study. Significantly higher proportions of surgical patients were female, belonged to the 60-to-79 age group, and were less severely ill. Also, extrinsic factors (invasive devices, hospitalization at the ICU, and prior antibiotics therapy) were more frequent in surgical patients. Prevalence of HAIs was higher among surgical patients (261/3626; 7.2%) than among non-surgical patients (258/8852; 2.9%) (p < 0.0001). The highest prevalence of all HAIs was noted in patients who had kidney transplantation (4/11; 36.4%), while SSIs were the most prevalent among patients who had peripheral vascular bypass surgery (3/15; 20.0%). Non-surgical patients received treatment for community-acquired infections in significantly higher proportion (2664/8852; 64.3) (p < 0.001). Surgical prophylaxis for more than 1 day was applied in 71.4% of surgical patients. CONCLUSION: We have provided an insight into the burden of HAIs and AMU among Serbia acute-care hospitals, and highlighted several priority areas and targets for quality improvement.

Surgical site infections in a tertiary health care center: prospective cohort study.

PURPOSE: To investigate the incidence and risk factors associated with the development of surgical site infections (SSIs) using the National Nosocomial Infection Surveillance (NNIS). METHODS: A prospective cohort study was conducted at a tertiary health care center. Infection control personnel collected general and health care related data about patients. The NNIS risk index was calculated on the basis of data relating to the operation: wound contamination class, duration of surgery, and the American Society of Anesthesiologists (ASA) score. RESULTS: A total of 5109 surgical procedures were included in the study. The overall cumulative incidence rate was 6.3%. The incidence of SSIs was 2.3% (63.5% of operative procedures), 8.3% (29.7%), 34.6% (6.2%), and 43.3% (0.6%), in patients with 0, 1, 2, and 3 risk index, respectively. The length of hospital stay (OR: 1.0; 95% CI: 1.053-1.075), preoperative length of stay (odds ratio [OR]: 1.9; 95% confidence interval [CI]: 1.953-1.981), antibiotic prophylaxis (OR: 2.5; 95% CI: 1.421-4.628), drainage (OR: 1.7; 95% CI: 1.360-2.353), ASA score (OR: 1.5; 95% CI: 1.235-1.946), class of wound contamination (OR: 2.0; 95% CI: 1.745-2.003), and NNIS risk index (OR: 1.3; 95% CI: 1.063-1.7) were independently associated with an increased risk for SSIs. Staphylococcus aureus was the most frequently isolated microorganism, 64% of them being methicillin-resistant. CONCLUSION: The aim of this study was to investigate the most important risk factors associated with the development of surgical site infections (SSIs). Therefore, greater attention has been given to adherence to recommendations for the prevention and control of SSIs as well as to antibiotic prophylaxis protocols.

Healthcare associated Clostridioides difficile infection in adult surgical and medical patients hospitalized in tertiary hospital in Belgrade, Serbia: a seven years prospective cohort study.

Introduction: Clostridioides difficile (C. difficile) infection (CDI) is one of the most common healthcare-associated (HA) infections in contemporary medicine. The risk factors (RFs) for HA CDI in medical and surgical patients are poorly investigated in countries with a limited resource healthcare system. Therefore, the aim of the study was to investigate differences in patients' characteristics, factors related to healthcare and outcomes associated with HA CDI in surgical and medical patients in tertiary healthcare centre in Serbia.Materials and Methods: A prospective cohort study was conducted including adult patients diagnosed with initial episode of HA CDI, first recurrence of disease, readmission to hospital, while deaths within 30 days of CDI diagnosis and in-hospital mortality were also recorded. Patients hospitalized for any non-surgical illness, who developed initial HA CDI were assigned to medical group, whereas those who developed initial HA CDI after surgical procedures were in surgical group. The data on patients' characteristics and factors related to healthcare were collected, too.Results: During 7-year period, from 553 patients undergoing in-hospital treatment and diagnosed with CDI, 268 (48.5%) and 285 (51.5%) were surgical and medical patients, respectively. Age ≥ 65 years, use of proton pump inhibitors, chemotherapy and fluoroquinolones were positively associated with being in medical group, whereas admission to intensive care unit and use of second- and third-generation cephalosporins were positively associated with being in surgical group.Conclusions: Based on obtained results, including significant differences in 30-day mortality and in-hospital mortality, it can be concluded that medical patient were more endangered with HA CDI than surgical ones.

Surgical site infection incidence and risk factors in thoracic surgical procedures: A 12-year prospective cohort study.

INTRODUCTION: Surgical site infections (SSI) continue to be a major problem for thoracic surgery patients. We aimed to determine incidence rate (IR) and risk factors for SSI in patients with thoracic surgical procedures. METHODOLOGY: During 12 years of hospital surveillance of patients with thoracic surgical procedures, we prospectively identified SSI. Patients with SSI were compared with patients without SSI. RESULTS: We operated 3,370 patients and 205 (6.1%) developed SSI postoperatively. We detected 190 SSI among open thoracic surgical procedures (IR 7.1%) and 15 SSI after video-assisted thoracic surgery (IR 2.1%). Five independent risk factors for SSI were identified: wound contamination (p = 0.013; relative risk (RR) 2.496; 95%, confidence interval (CI): 1.208-5.156), American Society of Anesthesiologist (ASA) score (p = 0.012; RR: 1.795; 95% CI: 1.136-2.834), duration of drainage (p < 0.001; RR: 1.117; 95% CI: 1.085-1.150), age (p = 0.036; RR: 1.018; 95% CI: 1.001-1.035) and duration of operation (p < 0.001; RR:1.005; 95% CI:1.002-1.008). CONCLUSION: The results are valuable in documenting risk factors for SSI in patients undergoing thoracic surgery. The knowledge and prevention of controllable risk factors is necessary in order to reduce the incidence of SSI.

Antibiotic consumption and healthcare-associated infections in a tertiary hospital in Belgrade, Serbia from 2011 to 2016.

INTRODUCTION: Healthcare-associated infections (HAIs) and irrational use of antibiotics in healthcare settings are major global public health concerns. Surveillance of HAIs in intensive care units (ICU), surgical-site infections (SSIs), and Clostridium difficile infections (CDIs), together with implementation of antibiotic stewardship, are cornerstones of hospital infection prevention programs. The aim of this study was to evaluate antibiotic consumption, especially of broad spectrum antibiotics, in relation to HAI incidence density (ID). METHODOLOGY: The study was conducted from 2011 to 2016 in a tertiary hospital, the Military Medical Academy (MMA), in Belgrade, Serbia. Through regular hospital surveillance we identified all patients with a new HAI. Data on consumption of antibacterials for systemic use were expressed as defined daily dose per 100 bed days (DDD/100 BD). RESULTS: The highest incidence density (ID) of HAI was observed among patients in surgical ICUs (47.2 per 1000 patient-days), while the highest incidence rate among SSI was 3.7%. Moreover, the highest ID of CDI in medical patients was 6.2 per 10,000 patient-days, while in surgical patients it was 4.3 per 10,000 patient-days. The most frequently used antibiotics were cephalosporins, aminoglycosides and carbapenems (16.0 ± 2.3, 4.8 ± 0.7, 4.3 ± 0.7 DDD/100 BD, respectively). There was no significant correlation between consumption of any groups of antibiotics and ID of CDI in medical and surgical patients. CONCLUSION: The multidisciplinary healthcare team would have crucial importance in the implementation of the antibiotic stewardship program in order to decrease unnecessary exposures of patients treated in healthcare settings.

Predictors of Hospitalization and Admission to Intensive Care Units of Influenza Patients in Serbia through Four Influenza Seasons from 2010/2011 to 2013/2014.

A retrospective analysis of the surveillance data on laboratory confirmed cases of influenza in 4 post pandemic seasons in Serbia was performed to evaluate predictors of hospitalization and admission to intensive care units (ICU). The specimens, including nasal and throat swabs were tested for influenza. Univariate and multivariate logistic regression analyses were performed. Data of a total of 777 confirmed influenza cases were analyzed. Age > 65 years, the presence of any co-morbidity or the presence of ≥ 2 comorbidities, infection with influenza virus subtype A (H1) pdm09, and an interval greater than 3 days between symptom onset and the first physician visit, were independently associated with hospital admission. These variables, as well as infection with non-subtype influenza virus A, were predictors for ICU admission. Obesity and chronic neurological disease were independent predictors for ICU admission but not hospitalization. Overall, 41.7% of patients with influenza had at least one co-morbidity, but only 3% of all patients were vaccinated against influenza. Identification of high risk groups and education of these groups regarding their increased susceptibility to severe forms of influenza, and in particular regarding the importance of influenza vaccination, is essential.

Risk factors for Clostridium difficile infection in surgical patients hospitalized in a tertiary hospital in Belgrade, Serbia: a case-control study.

BACKGROUND: The objective of this study was to investigate independent risk factors (RFs) connected with healthcare-associated (HA) Clostridium difficile infection (CDI) in surgical patients, its frequency per surgical wards and in-hospital-mortality at a single hospital. METHODS: Risk factors for the infection were prospectively assessed among surgical patients with laboratory confirmed HA CDI and compared with a control group without HA CDI. RESULTS: The overall incidence rate of HA CDI was 2.6 per 10000 patient-days. Significant independent RFs for HA CDI were the use of carbapenems (P = 0.007, OR: 10.62, 95% CI: 1.93-58.4), the admission to intensive care unit (P = 0.004, OR:3.00, 95% CI:1.41-6.40), and the administration of 3rd generation cephalosporins (P = 0.014, OR:2.27, 95% CI:1.18-4.39). Patients with HA CDI had significantly higher in-hospital mortality compared to controls (P: 0.007; OR: 8.95; 95% CI: 1.84-43.43). CONCLUSIONS: CDI is an important HA infection in population of surgical patients and this study emphasizes the importance of the wise use of antibiotics, and other infection control strategies in order to prevent HA CDI, and to decrease the incidence and in-hospital mortality rate.

In-hospital mortality analysis in patients with proximal femoral fracture operatively treated by hip arthroplasty procedure.

BACKGROUND/AIM: Hip fracture remains the leading cause of death in trauma among elderly population and is a great burden to national health services. In-patient death analysis is important to evaluate risk factors, make appropriate selection and perform adequate treatment of infections for patients to be operated. The aim of this study was to analyze in-hospital mortality in proximal femoral fracture patients operatively treated with hip arthroplasty procedure. METHODS: We followed 622 consecutive patients, and collected data about age, gender, the presence of infection preoperatively and postoperatively, American Society of Anesthesiologists (ASA) score, diabetes mellitus and the type of surgical procedure. Postoperative infections included pneumonia, urinary tract infections, surgical site infections and sepsis. RESULTS: We found a statistically significant influence of preoperative and postoperative infection presence for in-patient mortality with relative risk for lethal outcome of 4.53 (95% CI: 1.44-14.22) for patients with preoperative infection and 7.5 (95% CI: 1.90-29.48) for patients with postoperative infection. We did not confirm a statistically significant influence of age, gender, ASA score, diabetes mellitus or the type of surgical procedure for increased mortality rate. CONCLUSION: Adequate preoperative selection, risk evaluation and adequate treatment of infections are of the key importance for lowering the risk of death in patients operated due to proximal femoral fracture and treated by hip arthroplasty procedures. Special attention is to be paid for the presence of preoperative and postoperative infections in patients operatively treated due to the risk for increased in-hospital mortality.

Association of vascular endothelial growth factor expression with patohistological parameters of cutaneous melanoma.

BACKGROUND/AIM: Melanoma is the most aggresive malignant tumor of the skin. Contradictory data was published on vascular endothelial growth factor (VGEF) in tumor samples and its role in skin melanoma progression and prognosis. The aim of this study was to investigate the significance of VEGF expression as a prognostic parameter in melanoma. METHODS: The experimental group included 81 patients with primary skin melanomas treated from 2009 to 2013 at the Military Medical Academy, Belgrade. The control group included 20 patients with dysplastic and 20 with benign naevi. Stratification was done according to gender, age, clinical and patological stage, localization, histologic type, Clark's, Breslow, mitotic count, regression and ulceration, tumor infiltrating lymphocytes and metastatic spread.Immunohistochemical staining was performed on skin biopsies using DAKO anti-VEGF antibodies (Ab), LSAB+HRP, DAB and microvawe antigen (Ag) retrieval in DAKO pH 9.0 solution. For statistical data analysis was done with ANOVA, Bonferroni, Mann Whitney and Wilcox on test. RESULTS: The mean intensity of VEGF staining was statistically significantly higher in melanomas than in benign or dysplastic naevi. Furthermore, the highest recorded values were in Ia and IV clinical stages. The majority of melanomas with high intensity of VEGF staining were in pT1a pathological stage. Melanomas with the highest mitotic count (> 6) had a significantly higher intensity of VEGF staining than those with < 2 mitoses. The higest intensity of staining was in melanomas without significant lymphocytic infiltrate and the lowest was in those with brisk lymphocytic infiltrate, thus a statistical difference was siginifant. The mean intensity of VEGF staining was highest in melanomas with lymphovascular invasion. There was no statistically significant difference between VEGF and any other parameter. CONCLUSION: VEGF in primary skin melanomas plays an important role in tumor progression and is linked to the absence if tumor infiltrating lymphocytes and the presence of lymphovascular invasion. More detailed studies have to be done on VEGF prognostic value in melanoma on a larger number of patients.

Nosocomial bloodstream infections in ICU and non-ICU patients.

BACKGROUND: Nosocomial bloodstream infections (BSI) create a serious health problem in hospitals all over the world. The objectives of our study were to explore putative disease markers and potential risk factors with nosocomial BSI in patients in intensive care units (ICU) and non-ICU patients and to determine risk factors associated with increased 28-day mortality rate in patients with nosocomial BSI acquired in combined medical-surgical ICU. However, the major purposes of this report were to identify epidemiologic differences between nosocomial BSI acquired in ICU and non-ICU, as well as analyses outcomes for patients with nosocomial BSI acquired in ICU. METHODS: A 1-year prospective cohort study was performed to determine the incidence of nosocomial BSI in hospitalized patients. Patient characteristics, risk factors related to health care, and source of infection of patients with BSI acquired in non-ICU were compared with those patient with BSI acquired in ICU. Also, nested case-control study of patients to nosocomial BSI acquired in ICU was performed to evaluate outcome. Patients were identified by active surveillance and positive blood culture during the study period. RESULTS: The incidence of nosocomial BSI was 2.2 per 1000 admission in non-ICU patients and 17.4 per 1000 admission in ICU patients. The 28-day crude mortality rate was 69% in ICU patients. A multivariate model showed that nasogastric tube (RR, 25.1; 95% CI: 3.845-163.85; P=.001), mechanical ventilation (RR, 13.04; 95% CI: 1.974-96.136; P=.008), and H2 blockers (RR, 12.16; 95% CI: 1.748-84.623; P=.012) were more prevalent among patients with BSI acquired in ICU, and aggressive procedures (RR, 8.65; 95% CI: 1.70-44.00; P=.009) were more prevalent among patients with BSI acquired in non-ICU patients. Risk factors independently associated with increased 28-day mortality rate in ICU patients were mechanical ventilation (OR, 8.63; 95% CI: 1.5-49.8; P=.016) and SAPS II >40 (OR, 6.0; 95% CI: 1.0-35.7; P=.049). The most common isolated nosocomial BSI pathogens (in both groups of patients) were coagulase-negative staphylococci (21%), Staphylococcus aureus (14%), and Klebsiella species (13%). Klebsiella species was the only organism independently influencing the poor outcome of nosocomial BSI in ICU patients (OR, 4.3; 95% CI: 1.2-15.3; P=.022). CONCLUSIONS: Our results show epidemiologic differences between non-ICU and ICU BSI. Also, this study suggests that severity of underlying host conditions, mechanical ventilation, and microbial agents (Klebsiella species) affect the outcome of NBI in patients in ICU.

Surgical site infection surveillance in orthopedic patients in the Military Medical Academy, Belgrade.

BACKGROUND/AIM: Active surveillance is an important component of surgical site infection (SSI) reduction strategy. The aim of this study was to analyze and compare SSI surveillance data in orthopedic patients in the Military Medical Academy (MMA), Belgrade. METHODS: A 4-year prospective cohort study was performed to identify the incidence rate and risk factors for SSI in orthopedic patients in the MMA, Belgrade. We collected data regarding patients characteristics, health care and micro-organisms isolated in SSI. The National Nosocomial Infection Surveillance (NNIS) risk index was subsequently calculated for each patient. The Centers for Disease Control and Prevention criteria were used for the diagnosis of SSI. RESULTS: Assessment of 3,867 patients after different orthopedic operations revealed SSI in 109 patients. The overall incidence rate of SSI was 2.8% with the decrease from 4.6% in 2007 to 1.6% in 2010. Using NNIS risk index for surgical procedures there were: 53.7% (2,077) patients with risk 0--the incidence rate of 1.4%; 38.9% (1,506) patients with risk 1--the incidence rate of 3.1%; 7.3% (281) patients with risk 2--the incidence rate of 11.7%; 0.1% (3) patients with risk 3--without infection within the risk. Multivariate logistic regression analysis identified 6 independent risk factors associated with SSI: contaninated or dirty wounds, smoking, preoperative infection, NNIS risk index, body mass index and the length of hospital stay. CONCLUSION: The results of our study are valuable confirmation of relations between risk factors and SSI in orthopedic patients. A decreasing incidence rate of SSI (from 4.6% to 1.6%) during a 4-year active surveillance approved its implementation as an important component of SSI reduction strategy.