Determination of carbapenem resistance mechanism in clinical isolates of Pseudomonas aeruginosa isolated from burn patients, in Tehran, Iran

Carbapenems are the most important therapeutic options that effect against serious infections caused by multidrug resistant Pseudomonas aeruginosa [MDR-PA] isolates. Carbapenems resistant isolates of P. aeruginosa are increasing worldwide. The aim of this study was to determine the carbapenem resistance mechanisms in clinical P. aeruginosa isolates from burn patients, in Tehran, Iran. A total of 53 non-duplicated isolates of carbapenem-resistant P. aeruginosa were collected from burn patients. The presence of carbapenemase genes were determined by PCR. AmpC overproducer isolates were detected by phenotypic method. The mutation and transcription level of oprD were determined by PCR-sequencing and quantitative Real-time PCR [RT-PCR], respectively. Twenty-seven [50.9%] isolates were positive for carbapenemase [bla[vm] = 25 and bla[mp] = 2] and showed high-level resistance to imipenem and merope-nem. Twenty-eight isolates were AmpC overproducers. All isolates had a mutation in the oprD gene and down-regulation of oprD was found in 56.6% of MDR-PA isolates. Although the presence of carbapenemase is the common mechanism of resistant to carbapenem, but carbapenem resistance was found by oprD mutation-driven and the AmpC overproducing isolates in Tehran, Iran

Determination of asymptomatic Chiamydia trachomatis infections by omp1 gene based-PCR

The objective of this research was to determine the prevalence of genital C. trachomatis infection in asymptomatic women by using highly sensitive nested-polymerase chain reaction [PCR] in urine sample. One hundred-forty asymptomatic women were randomly selected from those who attended gynecology out patient department of Hazraate Rasool Hospital in Tehran. First catch urine specimen were collected from all the participants. DNA extraction was performed by means of High Pure PCR Template Preparation Kit [HPPTP] according to the manufacture's instructions. Extracted DNA was tested by omp1 gene based nested-PCR, using sets of primers to amplify C. trachomatis omp1 gene. Visualization of a 1027 bp fragment from omp1 gene in agarose gel electrophoresis was considered as a positive result. In total, 140 urines were tested for determination of C. trachomatis infection. C. trachomatis omp-1 was detected in 22.1% of cases [31/140]. The overall prevalence rates of C. trachomatis in the urine sample as determined by omp1 based nested-PCR were 4.3% in group I [age, <25 years], 12.1% in group II [age, 25-34 years], 5.0% in group III [age, 35-44 years] and 0.7% in group IV [>44 years]. The highest prevalence of C. trachomatis infection [12.1%] was seen in women aged 25-34 years. This finding was not statistically significant [p=0.710]. Also, there was not relation between C. trachomatis infection and some probable risk factors such as young age [<25 years], STD history and missing use of barrier contraceptive in this study. The prevalence of C. trachomatis infection in the women not seeking health care warrants more comprehensive study using high sensitive omp1 based nested- PCR to identify and treat a large number of infected women in Iran

[Identification of mycobacteria species in cutaneous lesions of sarcoidosis by PCR-restriction ragment length polymorphism [PCR-RFLP] method]

Sarcoidosis is a granulomatous multisystem disease of unknown etiology. It has recently been tired to detect Mycobacteria genome in biopsy specimens of patients with sarcoidosis by Polymorphism chain reaction method. To detect and identify Mycobacteria species in cutaneous lesions of the patients with sarcoidosis by PCR-RFLP. 20 patients with clinical diagnosis of sarcoidosis were enrolled in this study. Clinical manifestations, appearance of naked granuloma under light microscope and exclusion of other diagnoses confirmed the diagnosis of sarcoidosis in the patients. By PCR-RFLP, genome of Mycobacteria species was searched in paraffin embedded specimen of skin biopsies of the patients. Four PCR positive skin biopsy specimens of patients with cutaneous tuberculosis were used as positive control. 10 skin biopsy specimens with other than tuberculosis were used as negative control. Mycobacteria genome was not detected in any specimens of the patients. Our findings do not support the role of Mycobacteria species in the pathogenesis of sarcoidosis