Branislava Kocic

Analysis of antibiotic utilization and bacterial resistance changes in a surgical clinic of Clinical Centre, Nis

What is known and Objective:  There is little published information about antibiotic utilization and resistance amongst hospital inpatients in Serbia. The purpose of this study was to analyse the variation of antibiotic utilization and the relation between antibiotic utilization and bacterial resistance.

An In Vitro Synergistic Interaction of Combinations of Thymus glabrescens Essential Oil and Its Main Constituents with Chloramphenicol

The chemical composition and antibacterial activity of Thymus glabrescens Willd. (Lamiaceae) essential oil were examined, as well as the association between it and chloramphenicol. The antibacterial activities of geraniol and thymol, the main constituents of T. glabrescens oil, individually and in combination with chloramphenicol, were also determined. The interactions of the essential oil, geraniol, and thymol with chloramphenicol toward five selected strains were evaluated using the microdilution checkerboard assay in combination with chemometric methods. Oxygenated monoterpenes were the most abundant compound class in the oil, with geraniol (22.33%) as the major compound. The essential oil exhibited in vitro antibacterial activity against all tested bacterial strains, but the activities were lower than those of the standard antibiotic and thymol. A combination of  T. glabrescens oil and chloramphenicol produced a strong synergistic interaction (FIC indices in the range 0.21–0.87) and a substantial reduction of the MIC value of chloramphenicol, thus minimizing its adverse side effects. The combinations geraniol-chloramphenicol and thymol-chloramphenicol produced synergistic interaction to a greater extent, compared with essential oil-chloramphenicol association, which may indicate that the activity of the thyme oil could be attributed to the presence of significant concentrations of geraniol and thymol.

Correlation between antimicrobial consumption and antimicrobial resistance of Pseudomonas aeruginosa in a hospital setting: a 10-year study.

Antimicrobial resistance is one of the greatest threats to human health. One of the most important factors leading to the emergence of resistant bacteria is overuse of antibiotics. The purpose of this study was to investigate the correlation between antimicrobial usage and bacterial resistance of Pseudomonas aeruginosa (P. aeruginosa) over a 10‐year period in the Clinical Center Niš, one of the biggest tertiary care hospitals in Serbia. We focused on possible relationships between the consumption of carbapenems and beta‐lactam antibiotics and the rates of resistance of P. aeruginosa to carbapenems.

High-density cervical ureaplasma urealyticum colonization in pregnant women

BACKGROUND/AIM Ureaplasma urealyticum, a common commensal of the female lower genital tract, has been observed as an important opportunistic pathogen during pregnancy. The aims of this study were to determine the degree of cervical colonization with U. urealyticum in pregnant women with risk pregnancy and in pregnant women with normal term delivery and to evaluate the correlation between high-density cervical U. urealyticum colonization and premature rupture of membranes (PROM) as well. METHODS This research was conducted on the samples comprizing 130 hospitalized pregnant women with threatening preterm delivery and premature rupture of membranes. The control group consisted of 39 pregnant women with term delivery without PROM. In addition to standard bacteriological examination and performing direct immunofluorescence test to detect Chlamydia trachomalis, cervical swabs were also examined for the presence of U. urealyticum and Mycoplasma hominis by commercially available Mycofast Evolution 2 test (International Microbio, France). RESULTS The number of findings with isolated high-density U. urealyticum in the target group was 69 (53.08%), while in the control group was 14 (35.90%). Premature rupture of membranes (PROM) occurred in 43 (33.08%) examinees: 29 were pPROM, and 14 were PROM. The finding of U. urealyticum > or = 10(4) was determined in 25 (58.14%) pregnant women with rupture, 17 were pPROM, and 8 were PROM. There was statistically significant difference in the finding of high-density U. urealyticum between the pregnant women with PROM and the control group (chi2 = 4.06, p < 0.05). U. urealyticum was predominant bacterial species found in 62.79% of isolates in the PROM cases, while in 32.56% it was isolated alone. Among the 49 pregnant women with preterm delivery, pPROM occurred in 29 (59.18%) examinees, and in 70.83% of pregnant women with findings of high-density U. urealyticum pPROM was observed. CONCLUSION Cervical colonization with U. urealyticum > or = 10(4) is more frequent in pregnant women with risk pregnancy than in pregnant women with normal term delivery. High-density cervical U. urealyticum colonization should be observed as a possible etiological factor for PROM.

Enteritis caused by Campylobacter jejuni followed by acute motor axonal neuropathy: a case report

IntroductionCampylobacter species represent the main cause of bacterial diarrhea in developed countries and one of the most frequent causes of enterocolitis in developing ones. In some patients, Campylobacter jejuni infection of the gastrointestinal tract has been observed as an antecedent illness of acute motor axonal neuropathy, a variant of Guillain-Barré syndrome.Case presentationWe present a case of acute motor axonal neuropathy following infection with Campylobacter jejuni subspecies jejuni, biotype II, heat stable serotype O:19. A 46-year-old Caucasian man developed acute motor neuropathy 10 days after mild intestinal infection. The proximal and distal muscle weakness of his upper and lower extremities was associated with serum antibodies to Campylobacter jejuni and antibodies to ganglioside GM1. The electromyographic signs of neuropathic muscle action potentials with almost normal nerve conduction velocities indicated axonal neuropathy. Our patients clinical and electrophysiological features fulfilled criteria for the diagnosis of an acute motor axonal neuropathy, a subtype of Guillain-Barré syndrome.ConclusionAs this is the first case of acute motor axonal neuropathy following infection with Campylobacter jejuni subspecies jejuni reported from the Balkan area, the present findings indicate the need for systematic studies and further clinical, epidemiological and microbiological investigations on the prevalence of Campylobacter jejuni and its heat stable serotypes in the etiology of Guillain-Barré syndrome and other post-infectious sequelae.

Antibacterial activity chemical composition relationship of the essential oils from cultivated plants from Serbia

The antibacterial effects of essential oils from Serbian cultivated plants, Thymus vulgaris L. (Lamiace) and Lavandula angustifolia L. (Lamiace) on different bacteria were investigated, with an emphasis on an antibacterial activity-chemical composition relationship. Essential oil was obtained from airdried aerial parts of the plants by hydrodistillation for 3 h using a Clevenger-type apparatus. The essential oil analyses were performed simultaneously by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) systems. The main constituents of thyme oil were thymol (59.95%) and p-cymene (18.34%). Linalyl acetate (38.23%) and linalool (35.01%) were main compounds in lavender oil. The antibacterial activity of the essential oils samples was tested towards 5 different bacteria: laboratory control strain obtained from the American Type Culture Collection and clinical isolates from different pathogenic media. Gram negative bacteria were represented by Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 43895 and Salmonella enteretidis ATCC 9027 while researched Gram positive strains were Bacillus cereus ATCC 8739 and Staphylococcus aureus ATCC 25923. A broth microdilution method was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Essential oils from thyme have been found to have antimicrobial activity against all microorganisms tested, with a range of MIC values from 0.025 to 0.10 l/ml and MBC values from 0.05 to 0.78 l/ml. Lavender oils demonstrated MIC values from 0.025 to 0.20 l/ml and MBC values from 0.05 and 0.78 l/ml. Reference antibiotic tetracycline was active in concentrations between 0.025 and 0.05 l/ml. The Gram-positive bacteria were more sensitive to the essential oil of thyme, while Gram-negative bacteria were more sensitive to the essential oil of lavender. Essential oils from thyme and lavender may be used at low concentrations for prevention and treatment of infective diseases in animals and humans caused by pathogenic bacterial species.

Asymptomatic carriers of clostridium difficile in serbian population

The aim of the research was to determine the intestinal carriers of C. difficile in different human population groups in Serbia. The research enrolled 877 persons with formed stools: (newborn children in maternity hospitals for up to two weeks old) (23), group A; children aged from two weeks to two years (121), group B; children aged two to 10 years (54), group C, healthy individuals aged 10 and over (516), group D; patients hospitalized for at least 48 hours (100), group E; staff of the Clinical Center in Nis, Serbia, (63), group F. The toxins A and B of C. difficile were detected by ELISA-ridascreen Clostridium difficile Toxin A/B (R — Biopharm AG, Darmstadt, Germany). The toxin A of C. difficile was detected using ColorPAC Toxin A test (BectonDickinson, New Jersey, USA). Out of the total number of persons (877), the carriers of certain types of toxin-producing strains of C. difficile were distributed as: 6.04% (A−/B−), 1.83% (A+/B+) and 0.11% (A−/B+). In most groups (5/6), the dominance of non-toxigenic (A−/B−) isolates was established, with the rate of carriers 1.75 – 30.43% depending on the group. Toxigenic isolates were prevalent only in the group F in relation to non — toxigenic (7.94% versus 4.76% of persons). In other groups, the carriers of toxigenic strains ranged from 0.00 – 17.45%. The presence of asymptomatic intestinal carriers of C. difficile in the human population, indicate the possible reservoirs and sources of infection.

Survival of Campylobacter jejuni in chicken meat at frozen storage temperatures

The aim of this study was to determine the survival of Campylobacter jejuni in chicken meat samples at frozen temperatures and given length of incubation and to determine the impact of aerobic bacteria on the survival of C. jejuni. The chicken meat samples were inoculated with C. jejuni NCTC 11351 suspensions and stored in bags at temperatures of -20°C and -70°C. The mean value of C. jejuni from meat samples decreased from 7.52 log10 CFU/g after 30 minutes of incubation at ambient temperature, to 3.87 log10 CFU/g on the eighth week of incubation at -20°C, and to 3.78 log10 CFU/g at incubation at -70°C after the same incubation period. Both freezing temperatures, -20°C and -70°C, decreased the number of campylobacters. The presence of aerobic mesophilic bacteria did not influence the survival of C. jejuni in chicken meet samples. Keeping poultry meat at freezing temperatures is important for the reduction of C. jejuni, which has a strong influence on the prevention of occurrence of campylobacteriosis in humans.

Clinical importance of Clostridium difficile finding in hospitalized patients

INTRODUCTION Clostridium difficile infections predominatelly occur among hospitalized patients. The aim of this study was to evaluate the importance of finding the isolate of Clostridium difficile cultured from the stool of hospitalized patients. MATERIAL AND METHODS Material consisted of 100 patients with at least one liquid stool samples and control group with form stool. Every patient spent minimum 48h in hospital before the sampling. The material was immediately cultured on mediums for isolation of enteric pathogens, and on selective CCFA medium (Biomedics) for Clostridium difficile in anaerobic condition. Diagnosis of Clostridium difficile toxin in stool samples was achieved by ELISA-RIDASCREEN Clostridium difficile Toxin A/B test (R-Biopharm). RESULTS One-hundred forty one stool samples of patients in Clinical Centre Nis were cultivated and examined for C. difficile. The bacteria was isolated in seven patients from the clinical group. In four (57.14%) patients, the presence of C difficile toxin in stool was established The bacteria was diagnosed from the stool samples of five patients from the control group, but the toxin was not found in their stool samples. DISCUSSION The results performed at the Institute for Public Health Nis are in accordance with previously published results that all patients with positive findings of Clostridium difficile toxin in stool samples were on antibiotic treatment longer than 14 days. By analysing the patients stay in hospital and duration of antibiotic treatment, we observed the statistically significant difference in findings between the patients with CDAD and the patients from the control group with positive bacteria. CONCLUSION The study confirms the importance of finding Clostridium difficile associated disease in four (4%) hospitalized patients.

In vitro interactions of Peucedanum officinale essential oil with antibiotics

The chemical composition and antibacterial activity of Peucedanum officinale L. (Apiaceae) essential oil were examined, as well as the association between it and antibiotics: tetracycline, streptomycin and chloramphenicol. The interactions of the essential oil with antibiotics were evaluated using the microdilution checkerboard assay. Monoterpene hydrocarbons, with α-phellandrene as the dominant constituent, were the most abundant compound class of the essential oil of P. officinale. The researched essential oil exhibited slight antibacterial activity against the tested bacterial strains in vitro. On the contrary, essential oil of P. officinale possesses a great synergistic potential with chloramphenicol and tetracycline. Their combinations reduced the minimum effective dose of the antibiotic and, consequently, minimised its adverse side effects. In addition, investigated interactions are especially successful against Gram-negative bacteria, the pharmacological treatment of which is very difficult nowadays.