Tigecycline susceptibility of multidrug-resistant Acinetobacter baumannii from intensive care units in the western Balkans.

Tigecycline can be effective to treat infections of carbapenem-resistant Acinetobacter baumannii (CRAB) however, no interpretive criteria have been approved so far. The objectives of this study were to evaluate the proportion of CRAB isolates and to compare gradient test with a broth microdilution (BMD) method for tigecycline susceptibility testing of A. baumannii.This study included 349 multidrug-resistant (MDR) Acinetobacter spp. collected from Serbia, Montenegro, Bosnia and Herzegovina in 2016 and 2017. Antibiotic susceptibility testing was performed by disk diffusion, VITEK2, gradient, ComASP Colistin. Tigecycline susceptibilities were interpreted according to breakpoints of European Committee on Antimicrobial Susceptibility Testing (EUCAST) and Food and Drug Administration (FDA).Majority of the tested isolates were CRAB (92.8%). Tigecycline MIC50/MIC90 values were 4/8 µg/mL by BMD and 0.5/4 µg/mL by gradient test. Essential agreement for BMD and gradient test amounted to 65.1%. With EUCAST breakpoints, categorical agreement (CA) was achieved in 38% isolates. Major discordance (MD-false susceptibility/resistance) and minor discordance (mD-false categorization involving intermediate results) were observed in 10% and 57% A. baumannii, respectively. With FDA breakpoints, CA, MD and mD were observed in 44%, 16% and 47% isolates, respectively. Colistin resistance was 2.1%.The study highlights a high proportion of CRAB and several discordances between BMD and gradient test which may lead to inappropriate therapy.

Candida bloodstream infections in Serbia: First multicentre report of a national prospective observational survey in intensive care units.

Candida bloodstream infections (BSI) are a significant cause of mortality in intensive care units (ICU), hereof the prospective 12-months (2014-2015) hospital- and laboratory-based survey was performed at the Serbian National Reference Medical Mycology Laboratory (NRMML). Candida identification was done by a matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry and a susceptibility test, according to the Clinical and Laboratory Standards Institute methodology. Among nine centres (265 beds; 10 820 patient admissions), four neonatal/paediatric (NICU/PICUs) and five adult centres (ICUs) participated, representing 89 beds and 3446 patient admissions, 166 beds and 7347 patient admissions respectively. The NRMML received 43 isolates, 17 from NICU/PICUs and 26 from adult ICUs. C. albicans dominated highly in NICU/PICUs (~71%), whereas C. albicans and C. parapsilosis were equally distributed within adults (46%, each), both accounting for ~90% of received isolates. The resistance to itraconazole and flucytosine were 25% and 2.4% respectively. In addition, the 2 C. albicans were azole cross-resistant (4.6%). The overall incidence of CandidaBSI was ~3.97 cases/1000 patient admissions (4.93 in NICU/PICU and 3.53 in adult ICU). The 30-day mortality was ~37%, most associated with C. tropicalis and C. glabrataBSI. Data from this national survey may contribute to improving the Balkan and Mediterranean region epidemiology of CandidaBSI within ICUs.

Characterization of macrolide-resistant non-invasive pneumococci in the pre-vaccine era in Serbia.

Numerous reports have confirmed that increased macrolide use in the treatment of respiratory tract infection has contributed to the emergence of antibiotic resistance worldwide. Studies have also shown that pneumococcal vaccine can reduce pneumococcal resistance. The aim of this study was to determine the prevalence of co-resistance to penicillin and other antibiotics in macrolide-resistant (MR) non-invasive pneumococcal isolates and to evaluate serotype distribution in resistant strains in the pre-vaccine era in Serbia. About 80% of MR isolates expressed the MLS phenotype with very high resistance to both erythromycin and clindamycin. A total of 132 (84.1%) MR isolates were multiresistant, i.e., they were resistant to erythromycin, penicillin, tetracycline, and trimethoprim-sulfamethoxazole. Among 157 MR pneumococci, 11 different serotypes were found. Four serotypes, 19F, 14, 6B, and 23F, accounted for 77.7% of all MR pneumococcal isolates. Among isolates with the cMLS phenotype, serotypes 19F and 14 were predominant, whereas serotype 6A was the most common among those with the M phenotype, followed by 14. In conclusion, co-resistance to macrolides and penicillin in our non-invasive pneumococcal isolates is high. The majority of tested strains (∼80%) belonged to the four serotypes (19F, 14, 6B, and 23F) that are included in all conjugate vaccine formulations.

Streptococcus pneumoniae serotype distribution in Vojvodina before the introduction of pneumococcal conjugate vaccines into the National Immunization Program.

Introduction: Streptococcus pneumoniae is the most common causative agent of bacterial pneumonia and meningitis. Mandatory childhood immunization against pneumococcal diseases is introduced in the new Law on Protection of Population against Communicable Diseases in Serbia. Objective: The objective of this study was to determine the prevalence of pneumococcal serotype distribution in Vojvodina region before routine use of pneumococcal conjugate vaccine in Serbia. Methods: A total of 105 isolates of Streptococcus pneumoniae were collected in the period from January 2009 to April 2016. Based on the results of serotyping in the National Reference Laboratory, we analyzed distribution of circulating serotypes and coverage of conjugate and 23-valent polysaccharide pneumococcal vaccines in different age groups. Results: Among 105 isolates, a total of 21 different serotypes of Streptococcus pneumoniae were determined. The most frequent serotypes were 3 (21.9%), 19F (20.0%), and 14 (10.5%). The serotype coverage of pneumococcal conjugate vaccines (PCV7, PCV10, and PCV13) was 48.6%, 54.3%, and 84.8%, respectively, while pneumococcal polysaccharide vaccine (PPV23) covered 89.5% of the total number of isolates in all age groups. Serotypes included in PCV7, PCV10, and PCV13 represented 72.0%, 76.0%, and 88.0% of the total number of isolates in children ≤5 years, respectively. Vaccine serotype coverage of PCV13 and PPV23 ranged from 87.1% to 90.3% in adults 50­64 years of age, and 77.8% to 85.2% in adults ≥65 years old. Conclusion: Serotype distribution of Streptococcus pneumoniae in the population fairly overlaps with the serotypes contained in pneumococcal vaccines, so that implementation of childhood immunization is justified. The study was done in the Province of Vojvodina but the findings may be applied to Serbia as a whole.

The most common isolates from pleural infections.

Isolation and identification of the pathogens are important for appropriate treatment of pleural infections. Distribution of the most frequent causative agents varies throughout the world and may change in time.The objective of the study is to analyze the bacteriological isolates of pleural fluids in order to identify the most frequent infectious agents and assess their variability in time.The retrospective study included 272 patients with positive pleural fluid samples analyzed in 5-year period. The samples were examined using the conventional microbiological technique.Of 315 bacterial isolates the most common were streptococcal species, 105 (33%), of which 55 (17.3%) represented the Streptococcus milleri group. Gram-positive anaerobic cocci were detected in 56 (17.6%) isolates. Enterobacteriaceae family included 27 (8.5%) isolates and Pseudomonas aeruginosa was registered in 13 (4.1%). No statistically significant difference was registered in pathogen distribution in the examined period (p = 0.288).The most common agents of community-acquired pleural infections are the Streptococcus milleri group and anaerobic Gram-positive cocci. They differ from the most common pathogens of pneumonia. Among the hospital-acquired pleural infections, Pseudomonas species, Staphylococcus aureus and enterobacteria prevail. The distribution of bacterial agents isolated in the 5-year period exhibits no significant differences.

A postmortem analysis of major causes of early death in patients hospitalized with COPD exacerbation.

BACKGROUND: Mortality from COPD is increasing worldwide, but detailed causes of death are rarely assessed, particularly in low-income countries. METHODS: In a retrospective study, we reviewed the autopsy reports and medical records of deceased patients admitted to the hospital for severe exacerbation of COPD, from January 2005 to December 2007, at the Institute for Pulmonary Diseases of Vojvodina, Serbia. RESULTS: Forty-three patients with a hospital admission diagnosis of COPD exacerbation underwent autopsy; all had died within 24 h of admission to the hospital. Twenty-three patients (54%) had a long COPD history (> 10 years), and 19 patients (44%) had more than one hospitalization in the last year of life. The median age at death was 70 years (interquartile range, 65 to 75 years), and male sex was predominant (n = 31; 72%). The main (primary) causes of death were reported as cardiac failure (n = 16; 37.2%), pneumonia (n = 12; 27.9%), and pulmonary thromboembolism (PTE) (n = 9; 20.9%). Respiratory failure due to a progression of COPD was the primary cause of death in six patients (14%). Most patients had more then one comorbid disease (n = 33; 77%), and the most frequent comorbid disease was chronic heart failure (n = 25; 58%). CONCLUSIONS: Autopsy results suggest that common contributing causes of early death in patients hospitalized with severe COPD exacerbation are concomitant complications, as follows: cardiac failure, pneumonia, and PTE. Quality improvement interventions should focus on recognizing and treating these conditions at the time of hospital admission.