Asymptomatic carriers of Neisseria meningitidis and Moraxella catarrhalis in healthy children.

There is a close correlation between asymptomatic oropharyngeal colonization by bacterial pathogens and paediatric respiratory diseases. Evaluation of the frequency of asymptomatic carriers of Neisseria meningitidis and Moraxella catarrhalis in healthy children was the main aim of the current study. In this cross-sectional study, 123 oropharyngeal swabs were collected from children between 2 and 6 years old in kindergartens of Ilam, Iran. Moraxella catarrhalis and N. meningitidis were identified using phenotypic and genotypic assays. In addition, the occurrence of the virulence factors (ctrA and uspA1) and iron uptake (tbpA) genes was evaluated by PCR. Results showed that 21 M. catarrhalis isolates and 17 N. meningitidis isolates were identified by conventional microbiological and biochemical methods, but the RT-PCR assay detected that 18 and 8 isolates were positive for M. catarrhalis and N. meningitidis, respectively. The tbpA gene was positive in all N. meningitidis and M. catarrhalis isolates. Seven isolates were positive for the ctrA gene in N. meningitidis and seven isolates were positive for the uspA1 gene in M. catarrhalis. These pathogenic bacteria often occurred as asymptomatic carriage of N. meningitidis in children from large families with low economic status, which reflects the importance of the environment and socio-economic level of families in the distribution of these potentially pathogenic bacteria in the oropharynx of children. Monitoring for the carriage of potential pathogenic bacteria in the nasopharynx of healthy children is important as this can predispose to infectious diseases; common exposure to human respiratory bacterial pathogens is a further risk factor.

Rapid and direct molecular detection of Streptococcus pneumoniae and Haemophilus influenzae isolated in oropharynx and nasal cavity of children.

There is a direct correlation between asymptomatic oropharyngeal colonization by pathogenic bacteria and the prevalence of paediatric respiratory infections. Streptococcus pneumoniae and Haemophilus influenzae are common cause of serious bacterial infections such as meningitis in children. This study aimed to monitor healthy children to detect asymptomatic carriers of S. pneumoniae and H. influenzae. In the present cross-sectional study, real-time PCR assay was developed and evaluated in comparison with culture for direct detection of S. pneumoniae and H. influenzae in 123 oropharynx and nasal cavity specimens from healthy children in Ilam, Iran. In addition, virulence factor (ply and hpd) and iron uptake (tbpA and piuA) genes were evaluated by PCR. Our results demonstrated that among all isolates only 14 S. pneumoniae and eight H. influenzae were identified by phenotypic methods, whereas 37 and 21 S. pneumoniae and H. influenzae were identified, respectively, by real-time PCR assay. All S. pneumoniae and H. influenzae isolates possessed tbpA and piuA genes. Also, 81% (30/37) of S. pneumoniae isolates were positive for ply gene, which encoded pneumolysin, as well as 90% (19/21) of H. influenzae isolates were positive for hpd gene. Simultaneous colonization of S. pneumoniae and H. influenzae could indicate the importance of monitoring of healthy children to identification of carriers.

Mutation and Efflux System are Responsible for Ciprofloxacin Resistance in Klebsiella pneumoniae / Las mutaciones y el sistema de eflujo son responsables de la resistencia a la ciprofloxacina en la Klebsiella pneumoniae

ABSTRACT The main mechanism of quinolone resistance in Klebsiella (K) pneumoniae is caused by mutation of porin-related proteins and efflux pumps. This study aimed to investigate the prevalence of ciprofloxacin-resistant K pneumoniae in burns patients and to understand the role of the AcrAB multidrug efflux system on minimal inhibitory concentration (MIC) of ciprofloxacin. For this reason, 52 K pneumoniae samples were collected from burns patients and evaluated for the mechanism of ciprofloxacin resistance. The results demonstrated that 40 isolates of K pneumoniae were ciprofloxacin-resistant and 35 showed the mutation on gyrA locus. By inhibition of the efflux system, the MIC yield showed a significant decrease. Therefore, it could be concluded that the high rate of mutation on the gyrA locus in combination with quinolone resistance was responsible for ciprofloxacin resistance and by inhibition of AcrA, the resistance rate showed a significant decrease in K pneumoniae isolated from burns patients.

RESUMEN El principal mecanismo de resistencia a la quinolona en las Klebsiella (K) Pneumoniae tiene como causa la mutación de las porinas y las bombas de eflujo. Este estudio tuvo por objetivo investigar la prevalencia de las K pneumoniae resistentes a la ciprofloxacina en pacientes con quemaduras, así como entender el papel del sistema de eflujo multidroga AcrAB en la concentración inhibitoria mínima (CIM) de la ciprofloxacina. Por esta razón, se recogieron 52 muestras de K pneumoniae de pacientes con quemaduras, a fin de evaluar el mecanismo de resistencia a la ciprofloxacina. Los resultados mostraron que 40 aislados de K pneumoniae eran resistentes a la ciprofloxacina y 35 mostraron la mutación en el locus gyrA. Con la inhibición del sistema de eflujo, el rendimiento de CIM tuvo una disminución significativa. Por lo tanto, se pudo concluir que la alta tasa de mutación en el locus gyrA en combinación con la resistencia a la quinolona era responsable de la resistencia a la ciprofloxacina, y por la inhibición de AcrA, la tasa de resistencia mostró una disminución significativa en las K pneumoniae aisladas de los pacientes con quemaduras.

An ethnobotanical study of medicinal plants with narcotic, sedative and analgesic effects in west of Iran.

The first step for identification of medicinal plants and their therapeutic effects is to determine their use by local people, traditional medicine books and personal experiences. The aim of this study was to document the medicinal plants used as analgesic, sedative or narcotic agents by local residents of Dehloran, Iran. Interviews conducted with 53 informants (38 male and 15 female) revealed that a total of 32 medicinal plants belonging to 22 families are used in Dehloran as narcotic, sedative and analgesic agents. The most utilized plant families were Asteraceae, Rosaceae and Fabaceae. Approximately 74% of the utilized plants was attributed to herbs, followed by trees (13%) and shrubs (13%). Sixty-six percent of the medicinal plants used in the study area were perennial and the rest were annual or biannual. The most widely used plant parts were flowers (34%) followed by leaves (24%) and fruits (14%). Thirty-nine percent of the medicinal plants were used as sedatives, 39% as analgesics, and 24% as narcotics. Recommended plants in this study can be good candidates for further clinical and laboratory trials on diseases that are associated with pain, suffering, stress and depression. They also can be used to develop new sedative, narcotic and analgesic drugs.

Prevalence of high-level gentamicin-resistant Enterococcus faecalis and Enterococcus faecium in an Iranian hospital.

This study was designed to determine the molecular characteristics and antimicrobial resistance of enterococcal strains isolated from patients admitted to an Iranian Hospital. Enterococcal strains were isolated from the burn patients. All strains were screened for genes encoding resistance to aminoglycoside [aac(6')-Ie-aph(2'')-Ia, aph (3'), ant (4')], resistance to vancomycin (vanA, vanB), resistance to tetracycline (tetK, tetL, tetM, tetO), and resistance to erythromycin (ermA, ermB, ermC) by PCR and multiplex PCR-based methods. Genetic diversity was evaluated via Random Amplified Polymorphic DNA (RAPD)-PCR. All enterococcal isolates showed complete sensitivity to vancomycin with MIC ≤ 0.5µg/ml. Resistance to gentamicin, tetracycline, erythromycin, ciprofloxacin or quinopristin-dalfopristin was detected, whilst more than 96.2% of isolates were high-level gentamicinresistant (HLGR) and multiple drug resistant. The most prevalent aminoglycoside resistance gene was aac(6')-Ie-aph(2'')-Ia, that was found in 96.2% (26/27) of the isolates. The most prevalent tetracycline resistance genes were tetM, found in 85.1% (23/27) followed by tetL and tetO found in 7.4% (2/27) of the isolates. The ermA and ermB genes were detected in 33.3% (9/27) and 44.4% (12/27) of the isolates respectively. RAPD-PCR analysis yielded 17 distinct profiles among 27 investigated isolates. One cluster of isolates shared the same RAPD pattern, while 16 isolates had unique RAPD pattern. Our study showed that during the examination time period one RAPD genotype was the common type and was disseminated among patients in the burn unit. Interestingly, most of these strains had an identical or very similar antibiotic and gene resistance pattern.

The rationale behind antibiotic resistance pattern in Klebsiella pneumoniae.

Presently, there is an increase in antibiotic resistance in bacteria, due to relax prescription of antibiotics, especially in Iran. Undoubtedly, in toxin antitoxin (TA) system, a toxin neutralized by antitoxin, which known as a potent antimicrobial target; but there is no extensive survey on the prevalence of TA loci in large scale of Klebsiella pneumoniae. Therefore, this study aims to determine the prevalence of different TA loci in clinical and environmental K. pneumoniae isolates. For this reason, 48 K. pneumoniae clinical isolates and 49 K. pneumoniae environmental isolates were subjected for evaluation of different TA loci. The results of current study indicated that there is no association between antibiotic resistances and presence of TA loci in clinical and environmental K. pneumoniae. The role of TA loci as a potent target in antibiotic resistant K. pneumoniae has been complicated. Therefore, more studies should be performed to explain why TA loci are presented in K. pneumoniae and what is the rationale behind antibiotic resistant K. pneumoniae?

The prevalence rate of Porphyromonas gingivalis and its association with cancer: A systematic review and meta-analysis.

It seems that Porphyromanas gingivalis is carcinogenic, because it activates a number of inflammatory immune responses in the host and causes disorders in bacterial clearance mechanisms. There is little information on the prevalence of this bacterium in cancer patients. The aim of this study was to evaluate and compare the prevalence of P. gingivalis in cancer patients by meta-analysis methods.Different databases including PubMed, EMBASE, the Cochrane Library, Scopus, and ISI web of Knowledge were investigated and eight relevant articles published in 2000-2013 were finally analyzed. Data were analyzed by meta-analysis method, fixed effect model. I² statistics were calculated to examine the heterogeneity of papers. The information was analyzed by R and STATA Ver 12.2.A total of 711 people infected with P. gingivalis were included in this study. In total, the prevalence of P. gingivalis was 40.7% (95% CI, 19.3-62.1). The prevalence of P. gingivalis was evaluated in four case-control studies. The results of this study showed that P. gingivalis increased the chance of cancer development and periodontal disease as much as 1.36 times (OR, 1.36; 95%CI, 0.47-3.97).Although there was no significant correlation between P. gingivalis and cancer, this bacterium increased the chance of cancer and periodontal disease and could be considered as a main potential risk factor.

Unexpectedly high occurrence of Escherichia coli and Staphylococcus aureus isolates from raw milk in Ilam, Western Iran.

Raw milk contains diverse nutritional components that provide a suitable medium for spoilage and the growth of potentially pathogenic microorganisms. Unpasteurized milk consumption by a large number of people can threaten health and increase public concerns. In this study, sixty-two raw cow’s milk samples were collected from the dairy farms of Ilam, Western Iran. All samples were collected in sterilized containers and were transferred via ice boxes to the laboratory. Isolates were then identified by standard methods. Totally, 88.7% (n=55) of samples were contaminated. Our study also showed that Escherichia coli had a high prevalence among isolates (43: 69.4%), while Klebsiella pneumoniae and Klebsiella planticola showed the lowest prevalence (1: 1.6%). Staphylococcus aureus was also detected in 17.7% (n=11) of samples. The raw milk microbial contamination is complex. Some of the microorganisms threaten public health via different traits, therefore it is recommended that raw milk consumption should be avoided.

Enterococcus faecalis as multidrug resistance strains in clinical isolates in Imam Reza Hospital in Kermanshah, Iran.

The current study aimed to investigate the prevalence of vancomycin-resistant Enterococcus in E. faecalis and E. faecium and antimicrobial susceptibility patterns, then dominant genes responsible for vancomycin resistance were determined. For this propose, 180 clinical isolates of Enterococcus were subjected for identification and antibiotic susceptibility assay. Then, the gene responsible vancomycin resistant strains were determined. The results demonstrated the E. faecalis as a dominant Enterococcus. Resistance to erythromycin was dominant and multidrug resistance strains observed in E. faecalis. vanA was responsible for vancomycin resistance. In conclusion, a high rate of resistance to antibiotics in Enterococcus is clearly problematic, and a novel strategy is needed to decrease resistance in Enterococcus.

Frequency of bacteria causing urinary tract infections and their antimicrobial resistance patterns among pediatric patients in Western Iran from 2007-2009.

Urinary Tract infections ( UTIs) are among the most common infections in infants and neonates. The aim of the current study was to evaluate the frequency of bacteria causing UTI and their relevant drug resistance patterns among infants and neonates hospitalized in Ilam province, Western Iran during 2007-2009. A total of 220 cases of UTI were enrolled in this cross-sectional retrospective study. A standard checklist was used for demographic and clinical data to be collected from their health records. Data was then analyzed using SPSS version 16.0. More than two-thirds (64.8%) of the cases were female. E. coli (44.5%), Klebsiella spp., (18.6%), Enterobacter spp., (15%) and Staphylococcus spp. (12.7%) were the most common microorganisms isolated from UTIs, respectively. High rates of resistance to tetracycline, ampicillin, and nalidixic acid were observed among these isolates. Similar to other studies, E. coli was the most common bacteria causing UTI and showed a high rate of resistance against most of the antimicrobial agents. Determining the antimicrobial sensitivity can be helpful for physicians in choosing an appropriate treatment for patients suffering from UTI, and also to reduce the complications related to serious UTI.

Distribution of genes encoding tetracycline resistance and aminoglycoside modifying enzymes in Staphylococcus aureus strains isolated from a burn center.

Staphylococcus aureus (S. aureus) is one of the most common organisms associated with infections among burn patients and has shown a frequent and rapid development of antibiotic resistance. The presence of genes encoding aminoglycoside modifying enzymes (AME) and tetracycline resistance were detected by PCR and multiplex-PCR. Among the 151 S. aureus isolates recovered from the burn patients, 96 (63.6%) were detected to have mecA gene. The rate of tetracycline resistance genes associated with mecA was 61% (92/151). Forty nine isolates (32.4%) contained tetM, 26 (17.2%) possessed only tetK and 21 (13.9%) contained both tetM and tetK. The presence of the aac(6')-Ie-aph(2'')-I gene was determined in 18 isolates, aph(3')-IIIa in 8 isolates, both the aac(6')-Ie-aph(2'')-I, aph(3')-IIIa and the ant(4')-Ia genes in 69 isolates, both aac(6')-Ie-aph(2'')-I and ant(4')-Ia in 6 isolates, and both the aph(3')-IIIa and the ant(4')-Ia genes in 8 isolates. Most of the strains which harboured the mecA gene also contained the tet and AME genes.

Staphylococcus aureus (S. aureus) est l'un des organismes les plus communs associés à des infections chez les patients souffrant de brûlures et a montré une évolution fréquente et plus rapide de la résistance aux antibiotiques. La présence de gènes codant pour des enzymes de modification de l'aminoglycoside et de la résistance tétracycline a été détectée par PCR et PCR multiplexe. Parmi les 151 isolats de S. aureus récupérés des patients brûlés, 96 (63,6%) contenaient le gène mecA. Le taux de gènes de résistance à la tétracycline associés à mecA était de 61% (92/151). Quarante-neuf isolats (32,4%) contenaient tetM, 26 (17,2%) ne possédaient que tetK et 21 (13,9%) contenaient tetM et tetK. La présence du gène aac(6 ')-Ie-aph ('' 2)-I a été identifiée dans 18 isolats, et le gène aph(3')-IIIa dans 8 isolats. Les gènes aac(6 ')-Ie-aph(2'')-I, aph(3')-IIIa et ant(4')-Ia ont été identifiés dans 69 isolats, aaC (6 ')-Ie-aph (2'')-I et ant(4')-Ia dans 6 isolats, et l'aph (3')-IIIa et ant(4')-Ia dans 8 isolats. La plupart des souches qui hébergeaient le gène mecA contenait également des gènes tet et AME.

Distribution of extended spectrum beta-lactamase resistance genes among nosocomial imipenem resistant A. Baumannii strains harboring BLAoxa-23 carbapenemases isolated from Ilam and Tehran.

Antimicrobial susceptibility and ESBLs genes of 42 imipenem resistant A. baumannii carried out by DDST and PCR. The most antimicrobial agents against A. baumannii strains, harboring blaOXA-23-like carbapenemases, were meropenem (33.4 percent), piperacillin-tazobactam (23.9 percent), ceftazidime (14.3 percent) and gatifoxacin (19.1 percent), respectively. All the 42 isolates harbored the blaTEM gene, but the bla SHV and VEB genes were not present among all the isolates. With the exception of seven isolates, all the A. baumannii strains harbor blaTEM showed ESBL positivity in DDST. The result of this study show that resistance against antimicrobial agents, especially carbapenems, has increased and that blaTEM harboring A. baumannii strains can be help the blaOXA-like carbapenemase genes to code for resistance against carbapenem antibiotics.

Antimicrobial susceptibility patterns and distribution of blaOXA genes among Acinetobacter spp. Isolated from patients at Tehran hospitals.

Multiple drug-resistant strains of Acinetobacter have created therapeutic problems worldwide. This study was conducted to determine the antimicrobial susceptibility patterns and prevalence of bla(OXA-type) carbapenemases among isolates of Acinetobacter spp. obtained from Iranian patients. Here, 128 Acinetobacter isolates were identified at the species level, and their susceptibilities to different antibiotics were determined using disk agar diffusion testing. Isolates were then subjected to multiplex-PCR targeting bla(OXA) genes. More than 50% of the isolates showed multidrug resistance to different antibiotics. The rates of susceptibility to imipenem, meropenem, piperacillin-tazobactam, and amikacin were 50.7, 50, 42.1, and 38.2%, respectively. The MICs of carbapenems for the resistant isolates ranged from 64 to > or = 256 microg/ml. All strains of Acinetobacter baumannii possessed a bla(OXA-51-like) gene. The co-existence of bla(OXA-51-like)/bla(OXA-23-like) and bla(OXA-51-like)/bla(OXA-24-like) was detected in 25% (n=32) and 17.9% (n=23) of the isolates, respectively. Over 70% of carbapenem-resistant strains contained at least two genes encoding OXA-type carbapenemase. Resistance to carbapenems in the population of Acinetobacter strains in Iran is high, with the majority of isolates showing multidrug resistance. A wide diversity of OXA genes exists among the strains of A. baumannii in Iran. Detection of bla(OXA-51-like) can be used as a simple and reliable method to differentiate A. baumannii strains from other species.