Jundishapur Journal of Microbiology
Year:2011 | Volume:4 | Issue:1 (S.N. 10)|Papers Count:10

Hepatitis C virus (HCV) infection is a major public health in Iran as well as throughout the world. Health care workers (HCW) are occupationally at the risk of HCV infection. The aim of this article is to review the information about the epidemiology, nosocomial epidemiology, natural history, immunopathogenesis, and occupational risks associated with managing HCV in the health care workplace. Information obtained from previous investigation on HCV infection has yielded a better knowledge about HCV. Because data demonstrating the efficacy of any intervention are not yet available, no definitive post exposure anti viral therapy can be recommended for HCWs who are occupationally exposed to HCV. Based on existing data, the preemptive therapy and watchful waiting strategies outlined in this review article represent reasonable interim approaches to this complex problem.

Introduction and objective: Diabetic foot is the result of uncontrolled diabetes and imperfect sanitary care which leads to necrotic lesions, gangrene and finally amputation. Secondary mycotic infections play a principal role to produce chronic lumpy lesions. This study was designed to investigate the incidence of fungal pathogens in diabetic foot infections.Materials and methods: The study population included 120 consecutive diabetic patients who were hospitalized in the department of vascular surgery due to diabetic foot during 2006-2008. Direct fresh smear and fungal culture were performed for each patient. Fungal contaminations were confirmed by direct microscopy and/or culture.Results: The ages of the patients were between 32 to 86 years old. Of those 86(71.7%) individuals were male and 34(28.3%) were female. Direct examinations in 10% KOH were positive for fungal element in 25(20.8%) cases, but cultures were positive in 30(25%) cases.Candida species were the most predominantly isolated fungi (23 patients). Dermatophytic infection due to Trichophyton mentagrophytes was observed in three cases. The isolated opportunistic molds were known as Acremonium spp., Aspergillus fumigatus and Scopulariopsis spp. Significant correlation was found between infection, gender and age of the patients (P=0.0001 and P=0.0001). Conclusion: This study shows that fungal infection can be observed in about more than 20% of diabetic foot and causes a lesion with poor prognosis. The most common cause of mycotic diabetic foot is different species of Candida spp., especially C. albicans.

Introduction and objective: Acne is the most common skin disorder with a very high prevalence. Antibiotics have been used for more than 40 years against Propionibacterium acnes, the most common agent of acne. Antibiotic resistance of this bacterium was first reported in 1979, but became a worldwide problem in the recent years. The aim of this study was to determine the prevalence of antibiotic resistance among P. acnes isolates from acne patients referred to the dermatology clinics in Kerman, Iran during 2008-2009.Materials and methods: The samples were obtained from face and trunk lesions of 100 acne patients by a sterile swab and then inserted into a transport medium in which they were inoculated into two blood agar plates. One was incubated aerobically at 37°C for 24h and another one in anaerobic conditions at 37°C for one week. P. acnes was isolated, identified and antibiotic susceptibility of each isolate was determined by disk diffusion method. Results: Viable propionibacteria were detected in 57 patients. Thirty one percent of P. acnes isolates were resistant at least to one antibiotic. No resistance was seen to azithromycin and doxycycline. Lowest sensitivity was to clindamycin. Erythromycin resistance was low. No significant difference was detected in antibiotic resistance in the patients with and without treatment history and also no relationship was observed between P. acnes resistance and different body sites.Conclusion: P. acnes resistance to current antibiotics is a common problem and selection of appropriate antibiotics in order to decrease treatment failure and sequels of acne is an important issue.

Introduction and objective: Escherichia coli is an important group of pathogens associated with diarrhea among children. The objective of this study was to determine the frequency, antimicrobial susceptibility and plasmid profiles of E. coli pathotypes obtained from children with acute diarrhea.Materials and methods: In a prospective study during 2008, 466 rectal swabs of inpatient childrenwere examined for the presence of E. coli strains. Results: Of the total number of specimens examined, 99 (21.2%) were positive for E. coli. The highest number of isolates, 37(37.4%), was recovered from the 13-24 month age group. Of the 466 children, 191(41%) were girls and 275(59%) were boys. Based on the serological tests, 59(59.6%) of the E. coli strains were identified as enteropathogenic E. coli (EPEC) and 22 (22.2%) were identified as enteroinvasive E. coli (EIEC). The in vitro antibiotic susceptibility pattern of E. coli strains showed that 89.9 %, 88.9%, 79.8%, and 75% of isolates were found to be resistant to tetracycline, chloramphenicol, ampicillin and cefixime respectively. In plasmid profiling, out of the 99 E. coli pathotypes, 35 (35.4%) were found to possess plasmids, which ranged in sizes from 1.7kb to 4.5kb. These plasmids were seen in 33% of EPEC. Only two pathotypes possessed single size plasmid in EIEC.Conclusion: Our results revealed that EPEC, EIEC, enterohemorrhagic E. coli (EHEC), and enterotoxigenic E. coli (ETEC), had significant association with acute diarrhea among children in Sanandaj and should be considered as potential pathogens. Guidelines for appropriate use of antibiotics in Sanandaj need updating.

Introduction and objective: Outer membrane proteins (OMPs) of Brucella are considered as immunogenic structures which can be used to design and develop a subunit vaccine for human brucellosis. Brucella abortus S99 OMPs promote the synthesis of high levels of specific anti-Brucella IgG molecules in rabbits when administrated with lipopolysaccharide (LPS). The objective of this study is evaluation of the efficacy of B. abortus major OMPs with LPS in the induction of immune response against brucellosis.Materials and methods: OMPs were derived from B. abortus by sequential extraction of sonicated cells with ultracentrifugation and predigestion with lysozyme. Proteins could be separated by anion-exchange chromatography and gel-filtration. Based on SDS-PAGE profiles, porins have been dominantly purified among three different classes of B. abortus OMPs. Sera of immunized rabbits against B. abortus porins were analyzed by enzymelinked immunosorbent assay (ELISA). LPS of B. abortus and complete Freud's adjuvant (CFA) were also applied to elicit higher levels of anti-Brucella antibodies. Results: ELISA confirmed the potency of porins and porins combination with CFA and LPS to promote humoral specific response. Among the above-mentioned compounds, a combination of porins + LPS or porins + CFA has been the most potent immunogenic compound to induce higher titer of antibody against B. abortus S99 in the animal model.Conclusion: The application of a complex of Brucella LPS and porins as an effective method to elicit protective and long-lasting immunity against Brucella infection and would be studied to design and develop a subunit vaccine for human brucellosis.

Introduction and objective: Scorpion sting (SS) is a source of considerable morbidity and mortality in many parts of Iran such as Khuzestan a province south west, Iran. Inappropriate use of antibiotics results in microbial resistance as well as economic impact on health sector. The aim of present study was to identify the possible rate of secondary bacterial infection (SBI) among the patients with SS.Materials and methods: This was a retrospective study in which patient files with the diagnosis of SS were reviewed. The study was undertaken in Razi Hospital, Ahvaz. The hospital files of all patients managed for SS from 2003 to 2008 were reviewed. Diagnostic criteria for SBI were reasonable incubation period, clinical findings (e.g. cellulitis, abscess, and wound discharge) and laboratory clues (e.g. microbiological evidence, leukocytosis more than 10000 and polynucleosis more than 80%). The cases with positive culture results were considering as suspected SBI. Both SBI and suspected SBI considered being candidate for antibiotic therapy.Results: In the present study, 1381 patients were treated for SS. Out of total 1381 SS cases, 730(52.8%) were treated by antibiotic, whereas only 39 patients (2.8%) were suspected to be SBI. None of these SBI cases confirmed by bacterial culture. Conclusion: Secondary bacterial infection is a rare complication of SS. This study showed the unnecessary use of antibiotic drugs in the management of SS as a routine approach.

Introduction and objective: Esterase activity is used in evaluation and correlation of strains in fungi. Our previous study showed that Candida albicans has a kind of intracellular esterase activity in yeast extract, peptone, and glucose medium (YPG). The aim of this research was to study the qualitative and quantitative differences of this enzymatic activity among clinical isolates of this yeast.Materials and methods: Candida albicans isolates which have been kept on Sabouraud dextrose agar medium by continuous passage were grown in YPG medium for 48h in order to induce enzymatic production. In the next step, yeast cells were collected and then broken with glass bead. Esterase activity of cytoplasmic extract of isolates was measured by colorimetric method. Besides, five synthetic substrates were used to assess the qualitative differences in this enzymatic activity.Results: The cytoplasmic extract of 12 C.albicans isolates demonstrated an esterase activity to all used substrates and no significant qualitative and quantitative differences were found in this enzymatic activity. The average enzymatic activity of all isolates had a reversed relation to the number of carbon atoms in carboxyl substrates (except for alpha-naphtyle laurate). The amount of this activity for alpha-naphtyle acetate, beta-naphtyle acetate, alphanaphtyle caprilate, alpha- naphtyle laurate, and alpha-palmitate were 14.4, 8.45, 0.94, 0.42, 0.75 unit (mM/mg protein in min), respectively.Conclusion: The observed fluctuation in esterase activity of clinical isolates of C. albicans might be useful in tracking its sub species in epidemiological purposes.

Introduction and objective: The public vaccination program of hepatitis B virus was started in 1993 in Iran, and all children received three doses of hepatitis B vaccine in 0, 2 and 6 months of age routinely. The objective of this study was to determine the prevalence of antibody to hepatitis B surface (anti-HBs) five years after vaccination.Materials and methods: In a cross-sectional study, anti-HBs was determined in six year old girl and boy students of selected elementary schools of Ahvaz with enzyme-linked immunosorbent assay (ELISA) method in 2006. All children had received complete course of hepatitis B vaccination in the first year of age.Results: Four hundred and twenty seven students (223 girls and 204 boys) were enrolled in the study. Of them, 75.4% were anti-HBs positive (>10 mIU/mL). The prevalence of anti- HBs was statistically different between males and females (P=0.02).Conclusion: The study detected anti-HBs in 75.4% of children and because of possibility of presence of anamnestic responses in seronegative subjects, a booster dose of vaccine is not necessary at least five years after primary vaccination. Further studies are needed to evaluate hepatitis B immunity in older age groups.

Introduction and objectives: Typhoid is endemic in India; multidrug resistance of Salmonella enterica serovar Typhi has been reported from Kolkata, India, but nalidixic acid (Nx) resistance has not been documented in this part of the world. The aim of this study was to determine the Nx susceptibility for S. enterica serovar Typhi isolates (1991-2001) associated with enteric fever in Kolkata, India.Materials and methods: The clinical S. enterica serovar Typhi isolates (n=421) were subjected to Nx (the prototype quinolone, which is used for in vitro screening tests for fluoroquinolone resistance) susceptibility testing by disc diffusion and determination of minimum inhibitory concentration (MIC) values. The test results, from the two methods, were compared by scattergram analysis, and the sensitivity and specificity in determining Nx resistance by disc testing, with respect to MIC values, were calculated.Results: The S. enterica serovar Typhi isolates were categorized into resistant, intermediate and susceptible to Nx by disc testing and MIC. The isolates showed year-wise increment of Nx MICs (0.5-256mg/ml) during 1991-2001. High sensitivity (100%) and specificity (92.96%) in determining Nx resistance by disc testing, compared to MIC values were obtained for the isolates.Conclusion: Increasing trend of Nx resistance, as determined by two in vitro methods, among S. enterica serovar Typhi isolates was noticed; such Nx resistance may help predict decreased susceptibility to ciprofloxacin (an anti-typhoid fluoroquinolone) among emerging S. enterica serovar Typhi in our part of the globe.

Trichomonas vaginalis infection during pregnancy can cross into the amniotic fluid and result in preterm labor. Preterm birth is associated with poor infant health and early deaths, admission of the newborn to neonatal intensive care in the first few weeks of life, prolonged hospital stay and long-term neurologic disability including cerebral palsy [1]. Pregnant women with T. vaginalis are at increased risk for premature rupture of membranes (PROM), preterm delivery and low birth weight infants (LBW) [2-4]….