Iranian Journal of Infectious Diseases and Tropical Medicine
Year:2010 | Volume:15 | Issue:50|Papers Count:10

Background and objective: Several studies have reported increasing number of therapeutic failures with antiretroviral drugs in HIV-infected patients. The emergence of viral resistant strains is a major problem for the medical management of infected individuals. The aim of this study is to determine viral subtypes and drug resistance mutations among antiretroviral-treated HIV- infected patients.Materials and methods: A total of 42 antiretroviral-treated HIV infected patients were enrolled. The HIV pol region were amplified and sequenced to determine subtypes and antiretroviral resistant mutations.Results: The subtype distribution was 48% A/D recombinants, 43% subtype B, 5% subtype A and 5% CRF01-AE recombinants. Drug resistant mutations were most common in subtype B (53%) and A/D recombinant strains (44%). Virus samples from 19% of participants had no drug resistant mutations; 2%, 2% and 76% of samples carried 1, 2 and ³3 drug resistant mutations, respectively. The prevalence of NRTI mutations was 76%, with M184V and L74V present in 60% and 38% of samples, respectively. The prevalence of NNRTI mutations was 74%, with P225H present in 55% of study specimens. The prevalence of PI mutations was 45%, with major mutation L90M seen in 33% and minor mutation A71V in 36% of samples.Conclusions: Our study found a high prevalence of drug resistant mutations in Iranian HIVinfected patients. Our data support the need for continued surveillance of resistance patterns to help guide therapeutic approaches and limit transmission of these variants.

Background and objective: It is obvious that because of the lack of resources, we should devote our limited resources to priorities in order to reach an acceptable level of health. The objective of this study was research priority setting of infectious diseases using COHRED (Council on Health Research for Development) model.Materials and methods: This Health System Research (HSR) performed with participation of 16 research centers and dependent organization of Infectious and tropical disease network of Iran in 2009. First of all, the stakeholders were identified and the situation of the field of infectious diseases was analyzed. Then, research areas and titles were specified Finally, research priorities were specified by giving scores according to the criteria.Results: eighteen research areas were obtained as priorities of national infectious diseases network. These areas are nosocomial infections, HIV/AIDS, sexually transmitted infections, seasonal flu, H1N1 and avian flu, infectious disease surveillance system, preparedness in different levels of health system for pandemics, epidemics, outbreaks, disasters and unpredicted events, The role of migrants in the distribution of Infectious diseases in Iran, drug resistance, pulmonary tuberculosis, protecting health personnel and needle stick injury, pneumonia, meningitis, acute viral hepatitis, brucellosis, infections in high risk and special hosts, viral hemorrhagic fevers of vector born fevers, gastrointestinal infections and food poisoning.Conclusion: eighteen fields defined through studying 78 research priorities. Three subheadings including surveillance system, epidemiology, prevention and control methods got the most priorities, respectively. Although about half of the priorities were the same as last priority setting in 12 years ago, but there was more attention on health system preparedness, emerging and reemerging diseases, bioterrorism and surveillance system in this study.

Background and objective: Hepatitis C virus (HCV) and Hepatitis B (HBV) infection are especially problematic in patients with end-stage renal disease (ESRD) who are undergoing hemodialysis.Materials and methods: In a cross sectional study, from May to September 2009, in 11 different hemodialysis (HD) units in the north of Iran, clinical data such as age, sex, HBsAg, anti- HCV antibody and dialysis duration of hemodialysis patients were recorded. Patients with positive antibodies to HCV were tested for detecting HCV RNA.Result: From 514 patients 286 (55.64%) were male. In this study, 1.4% of patients were HBsAg positive, and (11.9%) were anti HCV positive. From anti HCV positive cases 52.5% were HCV RNA positive over all (6%) of patients were HCV PCR positive. There is significant relationship between HCV Ab positivity with sex and dialysis duration (p<0.05).Significant relationship was found between HCV RNA positivity with sex and dialysis duration (p<0.05). There is significant difference between mean of dialysis duration in anti HCV positive and anti HCV negative patients.  (p<0.05) Two cases (0.38 %) of dual infection of HBs Ag and Anti HCV Ab positivity were indentified.Conclusion: There is low prevalence of Hepatitis C and B in hemodialysis population of our region and It can be decreased by HBV vaccination, Antiviral Treatment and isolation of infected individuals.

Background and objectives: Helicobacter pylori contributes to the development of peptic ulcers and gastric cancer. The most well-known virulence factor of Helicobacter pylori, CagA, is translocated into gastric epithelial cells and localizes to the inner surface of the plasma membrane, in which it undergoes tyrosine phosphorylation at the Glu-Pro-Ile-Tyr-Ala (EPIYA) motif. Four segments flanking the EPIYA motifs, EPIYA-A, -B, -C, or -D, were reported to play important roles in H. pylori-related gastroduodenal pathogenesis. The aim of this study was to determine the roles of EPIYA segments in gastroduodenal pathogenesis in an Iranian population.Materials and methods: A total of 92 cagA-positive Iranian strains isolated from dyspepsia patients with non-ulcer dyspepsia (n=77), peptic ulcer (n=11) and gastric cancer (n=4) were studied. The EPIYA motif genotyping was determined by polymerase chain reaction and sequencing.Results: 86 (93.5%) strains had three copies of EPIYA (ABC type), three (3.3%) had four copies (ABCC type) and three (3.3%) had two copies (AB type). The alignment of the deduced protein sequences confirmed that there were no East Asian type EPIYA-D sequences (EPIYATIDFDEANQAG) in Iranian strains.Conclusion: The structure of the 3 region of the cagA gene in Iranian strains was Western type. Although we could not find differences between EPIYA types and clinical outcomes, low prevalence of strains with multiple EPIYA-C segments might be reasons for low incidence of gastric cancer in Iran.

Background and objectives: Staphylococcus epidermidis is a normal constituent of healthy human microflora, but it is also the most common cause of nosocomial infection associated with the use of indwelling medical devices such as implanted catheters and prosthetic devices. S. epidermidis has the ability to produce biofilm and it has been proposed that this characteristic is the most important pathogenic factor of foreign-body infections caused by S. epidermidis. The aim of this study was the phynotypic investigation of biofilm production ability by qualitative (congo red agar test) and quantitative (microtiter plate test) methods and comparison of antibiotic resistance pattern between S. epidermidis strains isolated from hospitalized and healthy persons.Material and methods: In this study 55 S. epidermidis strains from hospitalized patients in one of the Tehran hospitals and 23 strains from healthy persons were collected and identified by using of routine test (Gram stain, catalase test, cuagolase test, DNase, PYR, novobicin disk, urease, monnitol, trehalose). Biofilm production was examined using qualitative (congo red agar [CRA]) and quantitative (microtiter plate [MTP]) techniques. Antibiotic resistance patterns were performed by disk diffusion method.Results: according to the congo red agar results, 45 (81%) S. epidermidis strains were biofilm positive, 5 (9.5%) S. epidermidis were biofilm negative and 5 (9.5%) S. epidermidis were unknown in biofilm production. Congo red agar results for the healthy strains showed 3 (13%) strains were biofilm positive, 14 (61%) strains were biofilm negative and 6 (26%) strains were unknown. In quantitative method investigation in hospitalized patients, 36 (65.5%) S. epidermidis strains were strong adherent, 14 (25.5%) strains were weakly adherent, and 5 (9%) strains were non-adherent. In healthy volunteers, 5 (21.5%) S. epidermidis strains were strong adherent, 5 (21.5%) strains were weakly adherent, and 13 (57%) strains were non-adherent. Antibiotic resistance rate to oxacilin, penicilinG, erythromycin, clindamycin, ciprofloxasin and co-trimoxazole in hospitalized strains were 82%, 91%, 74.5 5, 51%, 49%, 65.5 % respectively. In healthy strains rate of resistance were 22%, 56.5%, 13%, 4.3%, 4.3%, 26% respectively.Conclusion: biofilm production was more common among hospital strains in comparison to healthy trains by both two methods. In 75% of cases, Results of qualitative and quantitative tests were compatible. Antibiotic resistance rate in hospital strains were higher than healthy strains. In nosocomial infection, these characteristics of S.epidermidis (biofilm production and antibiotic resistance) can be used to distinguish between invasive strains and normal flora.

Background and objective: Salmonella infections is an important public health problem. In the world. Nontyphoidal gastroenteritis of Salmonella are commonly self limited, but treatment with third generation of cephalosporines are a suitable choice for enteric fevers and invasive salmonellosis. Resistance to these antimicrobial and production of extended-spectrum betalactamases (ESBL) in bacteria have been increased recently. blaCTX-M-type enzymes belong to class A group of ESBL which rapid spreading among Enterobacteriacea is a major epidemiologically problem. The aim of this study is to determine the type of blaCTX-M in Salmonella spp.Material and methods: 174 Salmonella Spp isolated from stool culture of patients with gastroenteritis symptom during July 2007 to December 2009. Due to screen ESBL-producers strains, the isolates were tested for antimicrobial susceptibility by fifteen antibiotic using disk diffusion method.Suspicious strains were tested by Kirby-Bauer, combined disk and minimal inhibitory concentrations methods. ESBL positive strains were tested for blaCTX-M, bla TEM and blaSHV genes by PCR.Results: according to antibiogram susceptibility tests, the highest resistant rate belongs to nalidixic acid (49.4%) and tetracycline (43%). phenotypic tests were shown that seven strains were ESBL positive. DNA sequencing of PCR product reveals that the all bla CTX-M positive strains (n=6) belong to CTX –M-15 classes.Conclusion: increased dissemination of broad spectrum beta lactam mediated by bla-CTX-M 15, in Salmonella in Iran, suggests that its incidence in Enterobacteriaceae to be monitored. Horizontal transfer and expression of this gene among Enterobacteriaceae lead to present of high level ESBL-producing bacteria in future.

Background and objective: Determination of the relatedness of microbial isolates has become increasingly important as the number and spectrum of nosocomial pathogens continue to expand. Indeed, this approach is critical to identifying outbreaks, to determining the mode of acquisition of pathogens, and, accordingly, to defining effective preventive and therapeutic measures. The present study, was conducted to determine of the relatedness of Pseudomonas aeruginosa isolates obtained from wound and burn infections in Imam-khomaini, Tohid and Motahari hospitals in Tehran during 1999-2006.Material and methods: A total of 74 P. aeruginosa isolates (34 burn, 40 wound isolates) was obtained from patients during 1999-2006 of Imam-Khomeini, Tohid and Motahari hospitals in Tehran. The isolates were identified as P. aeruginosa by biochemical tests. Chromosomal DNA of the isolates was extracted by Phenol-Chloroform method and used for ribotyping. Ribotyping was performed by using SmaI restriction enzyme.Results: 8 distinct ribotype patterns (A-H) obtained.43 (58.1%), 23 (31%) and 3 (4%) of the isolates belonged to A, B and C ribotype patterns respectively.5 (6.8%) of the isolates contained one of D-H ribotype patterns.Conclusion: Ribotyping indicated that the most of isolates (89%) clonally related and could be grouped into 2 major ribotype patterns. Persistence of clonal strains in these hospitals for many years indicate that is necessary to focus on reinforcement of measures for infection control.

Background and objective: The study compared the brain behavioral Activation/Inhibition system (BAS/BIS) between HIV positive patients and normal individuals.Materials and methods: Number of 50 HIV positive patients among HIV positive patients in Tabriz Health center was selected and were mached with 50 normal people as a control group. All Data were collected with demographic and Carver- White (BAS/BIS) questionnare. Statistical analysis with SPSS.17 software and statistical methods t-test was performed.Results: The mean age of HIV positive patients were 36.14±8.36. The frequency of family Separated from his wife, unemployment were fewer than the control group (P<0.01). The average of behavioral Activation systems in AIDS patients was stronger than normal peoples. No significant difference was found in behavioral inhibition systems between positive HIV patient and control peoples.Conclusion: Based on the results of this preliminary study it seems HIV positive patients have a stronger behavioral activation brain system. Further studies to identify more precisely the behavioral activation brain system interactions of high risk behavior are needed.