Iranian Journal of Infectious Diseases and Tropical Medicine
Year:2004 | Volume:8 | Issue:23|Papers Count:18

Staphylococci are the most common pathogens in hospital and community acquired infections. Beta lactam drugs, especially third generation cephalosporin's have been used to treat these infections. However, 80-90% of Staphylococci have become resistant by producing beta-lactamases and methicillin resistance is increasing in both coagulase positive and negative Staphylococci. According to a suggestion made by the NCCLS, the use of penicillin and oxacillin is sufficient in predicting susceptibility to all other beta-lactams. In this study, 67 isolates of Staphylococcus including 42 S. aurous, 23 S. epidermidis and 2 S. saprophyticus, were collected from two health centers in Tehran. The antibiotic sensitivity to Penicillin, Ampicillin, Oxacillin, Cephalexin, Cefazolin, Ceftazidime, Amoxicillin-clavulanic acid and Ampicillin-Sulbactam was determined using the disk diffusion method. Beta-lactamase production was also measured by two assays using single colonies, the iodometric technique and nitrocefin disks (cefinase). The results showed that all S. aurous isolates were resistant to penicillin and produced beta-lactamase. Oxacillin resistance was observed in 45.5% of the isolates. Among coagulase-negative staphylococci, 92% were penicillin resistant and 48% were also resistant to oxacillin. Only one oxacillin resistant strain did not produce beta lactamase. 15.2% of MRSA and 58% of MRCNS were sensitive to the other tested beta-lactams.

Introduction: Unlike many environmental bacteria, Pseudomonas aeruginosa has a remarkable capacity to cause disease in susceptible hosts. It has the ability to adapt and thrive in many ecological niches from water, soil to plants and animal tissues. Pseudomonas is one of the most frequent causes of nosocomial infections. This organism usually appears as an opportunistic pathogen which can invade patients with impair defenses, The purpose of this study was to compare the antibiotic resistance and plasmid profiles in Pseudomonas aeruginosa isolated from different sources. Method: In a prospective study, 70 Pseudomonas aeruginosa isolated from different sources (40 from burn patients of shahid Motahary Hospital, 7 from urinary tract infections of Labafi nejad hospital and 23 from vegetables and soil) were isolated and identified. Resistance to antibiotic of them were determined by Kirby-Bauer method. Plasmid profile's of isolated bacteria were done on a horizontal electrophoresis on agarose gel, detected and photographed. Results: Results indicated that the Pseudomonas aeruginosa isolated from burn infections were resistance to sulfametoxazol trimetoprim, cefalexin, ceftizoxim, (100%) and all Pseudomonas aeruginosa isolated from environmental sources (vegetables, soil) were sensitive to ciproflaxacin (100%). Plasmid profiles analysis showed that the Pseudomonas aeruginosa isolated from burn infections with 1-3 Kbp and from urinary tract infections with 1.5-3 kbp and from environment with 1.5-2.5 kbp molecular weight. Discussion: The results showed that the antibiotic resistance and plasmid profiles of different sources of Pseudomonas aeruginosa were varied. This showed bacterial response to different ecological niches (clinical and environmental life). In this study, all isolates were resistant to trimetoprim- sulfametoxazol, cefalexin and ceftizoxim, that indicated probably intrinsic resistance. Antimicrobial susceptibility testing of all isolates is crucial for the treatment of infection.

Introduction: Medical instrument contamination is one of the most important factor for infection transmission from patient to another patient. The different parts of medical stetoscope as a  potential source of transmission of harmful microorganism in nosocomial infection. The aim of this study was to determine the bacterial contamination in medical stethoscopes (ear pieces and diaphragm) as a one of the factor involve in transmission of nosocomial infections. Methods: The stethoscopes (n = 60) of the medical personal (Nurses, Physicians and student) of the educational hospitals in Semnancity, were cultured. In this study we investigated Both diaphragm and earpieces of stethoscopes and cultured separately. By means of a swab, which was wetted in sterile normal saline, sampling from earpieces and diaphragm performed and cultured on blood agar media. After 24h of incubation and by means of Gram's staining, .catalase test, culture on M.S.A and coagulase test. Results: Result showed that stethoscopes contaminated was 83% and 75% in diaphragm and earpieces respectively. Staphylococci coagulase negative Staphylococci coagulase positive and Bacillus were isolated from diaphragm and earpieces respectively. Conclusion: Finding above showed that stethoscope may be an important factor in the spread of nosocomial infections agents, So that a policy regarding cleaning stethoscopes with an effective disinfectant may be helpful in reducing nosocomial infection.

Every year in the province of Isfahan various cases of malaria had been reported. Epidemiological investigation of this infectious disease in different areas of the country can play a significant role in employing preventive measures as well as in managing logestic service. Methods: Present survey is a descriptive cross sectional study, that indicates positive cases of malaria reported in health centers and from the center of communicable diseases in lsfahan province from present. The data were entranced to personal computer according to demographic characters of patients, plasmodium species, total forty in countries and the data were analyed by EPI 6 soft ware. Finding: A total 4462 cases disease reported and one type of species of malaria parasite were detected in their blood smear. The highest number positive cases (1069) in 1998 and the lowest number (495) in 2000 were reported consequently (Pv<.001). From the total number of cases, 93. 2% of the individuals infected were Afghan refugees and 2.54% were other Iranian immigrants or passengers who came to Isfahan province from malaria areas (Pv<.05). The highest number of cases, 39.44% belong to the age group 20-29 and in male ere 83.18% (Pv<.05). The annual parasite incidence rate that was 0.3/.000 in 1998 was decreased to 0.23/000 in 2002. Annual blood examination rote(ABER) was 0.67.1.31 positive rate Was1.9- 3.4 percent in recent years percent and slid.Conclusion: Due to the parasitic recourses (incoming trible people from neighborhood provinces - incoming Afghan people) and the availability of carriers more precise search for the patients, vectors and Complementary studies seems necessary

Introduction Tuberculosis disease is one of the major health problems in the world, especially in developing countries it is essential to control the disease and to eradicate it from the communities. Identify patients and treat them is the best2nd the most effective way to its eradication. Several approaches to screening have been mentioned in different studies. It seems that the most appropriate method economically is screening based on chronic cough. For this reason, in this study patients with chronic cough were examined as the target population. The prevalence of tuberculosis were assessed in them and compared with other studies. Methods and materials: This is a cross-section observational study which was conducted during 1997-1999. Target population included patients attended rural and health-care centers who had chronic cough with sputum. A questionnaire includes personal information, observation and physical examination was used to collect data. For those who had chronic cough, a sputum smear was taken and sent for laboratory exams. Patients with tuberculosis were diagnosed by different methods. Findings: 457 patients with chronic cough were entered the study. Only 18.4% of them had a report on their sputum smears. 11.6% (52) were diagnosed with pulmonary tuberculosis. The average age of patients with TB was 48.3 =17, which is significantly higher than those without TB. The average length of cough duration in patients with TB was 29.58±55.7 weeks, which was significantly higher than those without TB. In terms of the quality of cough. 85% of TB infected had cough with sputum and 35% had sputum with blood. The most common symptoms in TB infected included night sweating, fever for more than one week and losing significant weight, whereas, post nasal drainage with cough were common in others. Discussion: Although, screening based on chronic cough (more than three weeks)is the most appropriate  method. But after failure of one duration therapy with antibiotics sputum smear tests showed that 26% of patients had tuberculosis. Considering the risk of tuberculosis transmission in the community, it is recommended that. Firstly, screening based on chronic cough becomes an active practice, secondly, suspected patients with cough less than three weeks should be examined.

Objective: TTV is an undeveloped, single- stranded DNA virus that recently was discovered In general, TTV is transmitted parenterally and classified as a non-A-G virus group. The aim of this study was to evaluate the prevalence of TT virus in hemodialysis patients, were in high risk group for this virus. Methods: Serum sample of 55 patients (referred to Dialysis ward of Ekbatan hospital of Hamedan city) was tested for TTV -DNA by PCR. Results: TTV prevalence in our patients was 8(14.5%). Six(75%)TTV positive patients had history of blood transfusion but this frequency was 15.6% in other hemodialysis patients. Liver enzyme was not increased in any TTV positive patients and also they didn't have HBV or HCV co- infection. Conclusion: TTV prevalence in our patients is much lower than prevalence of other studies in different countries. Liver enzyme changes in TTV positive patients are adjusted with our study but HCV and HBV positive rate is higher than our study.

In order to determine the prevalence of gonococcal infection of genital tract in women, 1922 women between the ages of 15-44 were examined. This study was carried on by making smear from secretions of endocervical area by swabs and then by gram staining the slides. Among 1922 smears, 12 smears were positive regarding the gram negative diplococcus.

In view of the importance of tuberculosis in our country BCG vaccination is highly effective in preventing the development of tuberculosis immediately at birth. Material & Method: To assess the efficiency of BCG vaccination, a PPD test is applied to evaluate the sensitivity in a vaccinated individual. The size of reaction is under influence of some factors, including live organisms (CFU), strain, storing, dosage, vaccination technique and method. In this study, the inoculums of live BCG organisms in vaccinated infants at birth was evaluated and the correlation between amount of CFU and PPD reaction were examined at 3 months of age. For this purpose, 854 newborn infants in health centers affiliated to Shahid Beheshti University were studied at the age of 3 months. Tuberculin tests were performed in the pasteur Institute and other health centers. After health centers . After 72 hours, PPD induration diameter was measured. The comparison of the results with chi - square test showed there is a significant correlation between the two variables (size of PPD reaction and live organisms of BCG vaccination). Results: After evaluating live organisms in BCG vaccination, it was concluded that the amount of live organisms in many vaccines is more than 3 million while others are less. The following have been obtained as a result of assessment of PPD reaction in vaccinated infants: those vaccinated by live organisms, more than 3 million 93.4% showed PPD positive reaction but less than 3 million 69.2 showed PPD positive reaction. Thus, the number of live organisms in vaccination can play an effective role in the size of tuberculin skin reaction.