ABSTRACT
Helicobacter pylori has been strongly associated with peptic ulcer diseases, chronic gastritis, ulcers, and reported as a risk factor for gastric cancer, too. The vaculating cytotoxin [vacA], the cytotoxin associated genes [cagA], the induced by contact with epithelium factor antigen [iceA gene], blood adhesion binding antigen [babA2], and outer membrane protein oipA have been described as different virulence factors of H. pylori. The aim of this study was to investigate the prevalence of the vacA, cagA, cagE, iceA, babA2 and oipA genotypes of H. pylori isolates from patients with upper gasterointestinal problem or dyspepsia. H. pylori isolated from endoscopic biopsies obtained from 222 studied patients. PCR was done only on cultured positive samples. The vacA alleles, cagA, cagE, iceA, babA2 and oipA genotypes were determined by PCR. The isolation rate of H. pylori strains from culture of gastric biopsies was 16.7%. The vacA alleles s1, s2, m1 andm2 were detected in 20 [54.1%], 14 [37.8%], 9 [24.3%] and 23 [62.2%] isolates, respectively. VacA s1c genotype was detected in 70.3% of isolates. s1m2 was the most frequent vacA allelic combination in the examined H. pylori strains. ThecagA gene was detected in 62.2%, cagE in 40.5%, iceA1 in 48.6%, iceA2 in 16.2%, oipA in 81.1% [95% CI: 0.0902-0.1798] and babA2 in 94.6% [95% CI: 0.113- 0.207]. A significant correlation was observed between vacAs1 and cagA genotypes [P < 0.008], vacAs1/cagE [P = 0.001], vacAs2/cagA [P < 0.047], and vacAs2/cagE [P = 0.016] with Non-ulcer dyspepsia; but there were not observed any correlation between other virulence markers. No significant correlation was found between the existence of vacA, cagA, cagE, iceA, babA2, and oipA genes with peptic ulcer diseases and non-ulcer dyspepsia groups of studied patients
ABSTRACT
Streptococcus pneumoniae is an important problem worldwide and nasopharyngeal colonization plays significant role in pneumococcal infections. The aims of this study were to determine the nasopharyngeal colonization rate, serotyping, antibiotics susceptibility and study the risk factors for nasopharyngeal colonization with S. pneumoniae in students in Kashan, Iran. A cross-sectional study was conducted on children aged 7 to 19 years from December 2011 to November 2012. Nasopharyngeal swabs were plated onto brain heart infusion agar plates with 5% sheep blood and 4 micro g/ml of gentamycin. Antimicrobial susceptibility profiles were determined on Mueller-Hinton agar in accordance with CLSI. S. pneumoniae strains were investigated for the presence of the most common pneumococcal serotypes using a multiplex polymerase chain reaction. 13.9% were found to be carriers. The most prevalent serogroups were 19F [30%], 6A/B [18.9%], 15A [16.5%], 11 [11.3%], 23F [8.2%], 1 [6.2%], 19A [3.4%], and 35B [2.4%]. Nine strains [3.1%] were non-typeable. The carrier rate was significantly higher in 12 to15 year old age group. Upper respiratory tract infections within the last month [OR=1.5, P<0.011], previous hospitalization [OR=1.6, P<0.001], previous antibiotic usage last two weeks [OR=1.89, P<0.001], rhinorea [OR=1.9P<0.001], male sex [OR=3.5 P< 0.001] and passive smoking [OR=1.56, P< 0.001] have been determined to be risk factors for S. pneumoniae carriage. The highest pneumococcal resistance was to tetracycline [25.4%]. All strains were susceptible to linezolid and levofloxacin. Our information leads to an important source to screen the future impact of pneumococcal vaccination on bacterial colonization