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S Kalenić

Publications and source records attributed to S Kalenić.

32 records · Page 2Linked to original sources
PubMedDate not supplied

Helicobacter pylori: in vitro induction of resistance to azithromycin.

Helicobacter pylori resistance to macrolides is possibly an important factor for the failure of macrolide therapy for H. pylori infection. The aim of this study was to assess the propensity of H. pylori to develop in vitro resistance to azithromycin. In 73 clinical isolates taken from patients before starting antimicrobial therapy of H. pylori infection, MIC was determined using an agar dilution method (Müller-Hinton agar with 7.5% unlysed horse blood, pH = 7.2, at 35 degrees C, during 72 h in a humid microaerobic atmosphere). Each strain was first cultivated at half minimal inhibitory concentration (MIC) then in doubling concentrations until growth arrest. All experiments for induction of resistance were performed on the same media, incubation temperature, atmosphere and time of MIC determination. MIC interpretative standards for sensitivity, intermediate sensitivity and resistance of H. pylori to azithromycin were < or = 2, 4 and > or = 8 mg/l, respectively. Of 73 strains, 5 died during the experiments, and in the remaining 68 strains, serial passage with increasing azithromycin concentrations resulted in the development of resistance in 19 (26.9%) strains. Two strains had an MIC of 16 mg/l azithromycin. Thirty-three (48.5%) strains kept the same MIC or doubled their MIC, 16 (23.5%) strains had 4- to 16-fold MIC but still remained sensitive, 2 resistant strains had 128-fold MICs and 17 resistant strains had increased their MICs more than 128 times. Seventeen highly resistant strains (MIC > 128 mg/l) were kept frozen at -70 degrees C for 3 months in a brain-heart infusion broth with 15% glycerol. MIC was assessed again to determine the stability of resistance. Eleven strains kept MICs > 128 mg/l, 2 became sensitive and 1 intermediate, but reverted easily, after only 2 passages, to an MIC of > 128 mg/l azithromycin. Although macrolides are very active against H. pylori, the propensity to develop resistance in a high proportion of strains has a clear impact on the choice of the right combinations of macrolides with other agents as well as the dosage of the macrolide antibiotics.

Anti-Bacterial Agents↗
PubMedDate not supplied

[Guidelines for cleaning and disinfection/sterilization of endoscopes].

Endoscopy is a diagnostic and therapeutic method which is being increasingly used in various fields of medicine, especially in minimal invasive surgery. During the endoscopic procedure, endoscopes are contaminated with patient's microbial flora. After each procedure and before the next patient, endoscope should be reprocessed in a way to be safe from post-procedural infection. Endoscopes are divided in two categories (the borders between them are not always clear-cut): high-risk category endoscopes which enter the sterile tissue, and medium-risk category which come in contact with mucosal surface. High-risk endoscopes should be sterilized or high-level disinfected, and medium-risk should be high-level disinfected. The first and the most important step in endoscope reprocessing is thorough manual cleaning of all parts of dismantled endoscope and of all channels in water and (enzymatic) detergent. The second step is disinfection of endoscope fully immersed in 2% glutaraldehyde for 20 minutes at room temperature. The third step is thorough rinsing in sterile water or tap water followed by 70% ethanol, depending on the next endoscopic procedure. Steps 2-4 can be done in the machine. During endoscopy as well as during endoscope reprocessing, strict preventive measures should be followed for health care workers protection.

Disinfection↗
PubMedDate not supplied

[Monitoring bacterial resistance to antibiotics in the CroatianRepublic].

In 1996 a Committee for antibiotic resistance surveillance in Croatia was founded by the Croatian Academy of Medical Sciences. In this study antibiotic surveillance results for the period June 1-December 31, 1997 from 12 microbiology laboratories throughout Croatia are presented. Sensitivity to antibiotics was determined by disk diffusion method for the following bacteria: Streptococcus pneumoniae, Staphylococcus aureus, Enterococcus spp., Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa. In general, high proportion of resistant isolates was recorded throughout Croatia, although some regional variations were noticed. Mean resistance of pneumococci to penicillin was 38%, in S. aureus resistance to methicillin was 47%, and 3rd generation cephalosporin-resistance in E. coli was 6% and in Klebsiella spp. 21%. In P. aeruginosa resistance to gentamicin averaged 50%, to imipenem 13% and to ceftazidim 8%. Future aims of the Committee are to continue routine antibiotic resistance surveillance during certain periods every year, and to estimate clinical significance of resistant bacteria, detect mechanisms of resistance and improve the quality of laboratory work through education and quality control projects.

Croatia↗
PubMedDate not supplied

[Stenotrophomonas maltophilia as a cause of hospital infections--typing of clinical isolates using pulsed field gel electrophoresis] ].

Stenotrophomonas maltophilia (S. maltophilia) has been recognised now as an important cause of hospital infections. As S. maltophilia is resistant to many antibiotics, attempts have been made to identify the sources of S. maltophilia infection and route of its transmission. From July till October 1998, 22 isolates of S. maltophilia were obtained from 20 patients hospitalised at eight different wards. Strain typing was performed by macrorestriction analysis of chromosomal DNA by use of PFGE (XbaI and SpeI enzymes, in a CHEF DR III drive module). PFGE analysis of 22 S. maltophilia isolates revealed 9 different types designated by letters A to I. The source and route of the spread of infection could not be identified. These results may indicate that we had clusters of S. maltophilia infection in cardiosurgery ward and ICU by types A, B, C and D; in neurosurgical ICU by type E and in urology ICU by type H.

Bacterial Typing Techniques↗
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[Infections in war injuries].

Between April and September 1991, 415 injured patients were treated at the University Hospital Rebro, Zagreb, 362 at the Department of Surgery and 53 at the Department of Neurosurgery. Infections developed in 15.7% of the injured patients (wound infections in 14.6% and sepsis or meningitis in 1.1% of the injured patients). 88.2% of wound infections as well as all sepsis and meningitis were hospital-acquired infections, while 7.95 of wound infections occurred within 48 h of injuring. The major pathogens, in 90% of cases, were the aerobic bacteria (Enterobacteriaceae, Pseudomonas aeruginosa, Staphylococcus aureus, Acinetobacter species) while 9% of infections were caused by mixed aerobic-anaerobic flora. One injured patient developed clinical features of gas gangrene. Neither streptococcal wound infections nor tetanus were present in this group of the injured patients.

Humans↗
PubMedDate not supplied

[Sepsis caused by Yersinia enterocolitica in a female patient with liver cirrhosis].

As a primarily intestinal pathogen. Yersinia enterocolitica (Y. e.) may cause generalized infection in patients with malignant and other serious diseases or immunodeficient subjects. In certain conditions, elevated serum and tissue iron concentrations represent an additional risk factor for systemic infection with this opportunistic bacterium. In our patient, Y. e. septicemia developed during liver cirrhosis decompensation. Clinical signs of infection were alleviated by appropriate antibiotic therapy (gentamycin, cefuroxime), but as septicemia had been present for several days prior to therapy, it aggravated the patient's general condition, which entailed the development of hepatorenal syndrome and eventually lethal outcome.

Female↗
PubMedDate not supplied

[Treatment of neoplastic hematologic diseases with intensive radio-chemotherapy and transplantation of cryopreserved autologous bone marrow].

Autologous bone marrow transplantation (ABMT) allows application of intensive myeloablative therapy aimed at eradication of neoplastic disease by facilitating haematopoietic reconstitution. Between March and June 1988, four patients (two with acute myelogenous leukaemia in first remission, one with acute lymphoblastic leukaemia in second remission, and one with Burkitt lymphoma, stage IV with CNS involvement in second remission) received this treatment. Methods of collecting, processing and freezing bone marrow as well as thawing and reinfusion of the marrow into patients after intensive chemoradiotherapy are described. Viability of bone marrow cells tested by the dye exclusion method after freezing and thawing process was 89, 88, 91 and 78%, respectively. CFU-GM recovery in culture, as a test of marrow stem cells clonogenicity was between 63,3 and 156,5%. Patients received between 1,7 and 3,0 x 10(8)/kg nucleated cells and 4,0 to 7,6 x 10(4)/kg CFU-GM, respectively. In all four patients stable haematopoietic reconstitution was achieved. The bone marrow function was evident mainly at 11th day after marrow reinfusion. Leukocyte count reached 1,0 x 10(0)/L in 11 to 15 days, and granulocyte count raised more than 0,5 x 10(9)/L in 19 to 37 days after transplantation. Platelet recovery was prolonged with the minimum of 29 days and maximum of more than 60 days to reach 20 x 10(9)/L. Side effects caused by the intensive radiochemotherapy were moderate. Bacterial, fungal and viral infections in early posttransplant period were successfully treated. All patients have survived and left the hospital 63, 54, 36 and 65 days after ABMT, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone Marrow Transplantation↗
PubMedDate not supplied

[Seroprevalence of Helicobacter pylori infection in health personnel in 3 hospitals in Zagreb].

By this study we wanted to investigate the seroprevalence of H. pylori infection in 175 health care workers of three Zagreb city hospitals. The obtained results were compared with those of 2492 volunteer blood donors. The influence of age, education, socioeconomic status and length of service at specific hospital working places were investigated in relation to the frequency of H. pylori seropositivity. The blood samples were tested by commercial kits of immunoenzyme assay (ELISA) and complement fixation (CF), according to manufacturers instructions. The mean seroprevalence of infection was 58.6% in the group of blood donors and 53.7% in the group of health care workers (NS). Statistically significant difference was found between physicians (29%) and all other health care workers: nurses (58.6%; p < 0.005), laboratory technicians (60.6%; p < 0.005), clerical workers (66.6%; p < 0.005) and auxiliary workers (82.6%; p < 0.001). Concerning the age, the infection seroprevalence was higher in workers aged more than 40 years than in those younger, and that difference was of statistical significance among nurses and laboratory technicians. Physicians under 29 yrs were of the lowest seropositivity (14.8%). Among health care workers with less than 20 working years, physicians expressed the lowest rate of infection (17.9%) in comparison with nurses (48.5%) and laboratory technicians (53.3%). In all health care workers with more than 20 working years there was significant increase of infection prevalence, particularly among nurses. The employees in gastrointestinal endoscopy laboratories were more often serologically positive than medical workers in other medical departments (58.3% versus 35.0%; p < 0.05).

Adult↗