Tehran University Medical Journal

Background and Aim: While nowadays,great attainments have been achieved in curing and preventing the pathogenic fungal infections, and some how there has been reduction in the number of occurrences, the occurrences of opportunistic infections have been increased. Since the study of fungal infections in various organs (e.g.digestive system) is crucial ,and because of few study were done in this field in the world, it is decided to examine the apendectomide tissue for fungal contamination in Iran.

Materials and Methods: The work has been done for six months. After oparation sergery the appendix tissue in two media (formalin & normal salin) were carried out in the medical mycology laboratory at Tehran University of medical sciences. The specimens were examined directly and cultured in sabourauds dextrose agar with chloramphenicol (sc). In this experiment 200 appendicular tissues were examined.

Results: Out of them some fungi were isolated in 10 cases included 4 Candida albican (40%), 2 Candida tropicalis (20%),1 Cryptococcus sp. (10%),1 Candida sp.and 2 Geotrichum sp. Cryptococcus sp. was identified with mycological methods. This isolation related to a young man that has a history for long contact to pigeon.some of the fungi specially yeast can be a part of mycoflora in digestive system but the finding of Cryptococcus is uncommon.

Conclusion: In this study the fungi were isolated from 5% of appendisits and with pay attention to this finding that the most patients hadn.t background factors causing the proliferation of the fungal agents in the intestine, so with further studies it is probable to consider the fungi as the agents causing appendicitis in this patients.

Background: The clinical importance of yeast infections has increased in recent decades. There are 10-15 pathogenic Candida species. The current morphological and physiological methods for identification of Candida species are generally not easy to interpret and may be expensive or time-consuming. In the present study, we introduce and use a new approach for the identification and differentiation of medically important yeast species of Candida. In this method, size polymorphism of the internal transcribed spacer regions, ITS1 and ITS2, of the ribosomal DNA in various Candida species is used as the basis of species recognition.

Methods: The genomic DNA of 31 standard strains and 60 clinical isolates was extracted and PCR-amplified using two primer pairs (ITS1-ITS2 and ITS3-ITS4) separately. Both PCR products were mixed and analyzed after standard agarose gel electrophoresis. The species of the tested yeasts were identified by the electrophoretic patterns of the mixed PCR products of each sample, comparing the data obtained from the sequence analyses of ITS1 and ITS2 molecules.

Results: By this method, with the exception of C. albicans and C. dubliniensis, we were able to clearly differentiate nearly all common pathogenic Candida species, including C. albicans, C. glabrata, C. gulliermondii, C. parapsilosis, C. tropicalis,      C. krusei, C. kefyr, C. lusinaniae and C. rugosa. All standard and clinical strains were identified correctly, without expensive methods such as sequencing and capillary electrophoresis.

Conclusion: It seems that the PCR-FSP method introduced in this study is the easiest molecular approach for the identification of a wide range of pathogenic Candida species and is applicable for diagnostic and epidemiological purposes in reference laboratories.

Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background: Nocardiosis is a rare and potentially life-threatening infection caused by several species of the Nocardia genus. The objective of this study was to develop and evaluate a rapid and new method to clinically identify relevant Nocardia species. Rapid and accurate diagnosis of Nocardia species is essential for the treatment of severe infections and prevention of cerebral abscess.
Methods:  One hundred and eighty patients, 103 (57.22%) male and 77 (42.78%) female, with severe symptomatic pulmonary infection were studied in the course of a 12-month period in Dr. Shariati Teaching Hospital affiliated to Tehran University of Medical Sciences in 2010. The specimens were cultured and identified using microbiological and biochemical tests. Polymerase chain reaction (PCR) was used to directly identify the organism in the broncoalveolar lavage samples collected from the patients. NG1 and NG2 primers were used to amplify a Nocardia genus-specific 598-bp fragment of 16S rRNA.
Results:  Nineteen samples (10.56%) were positive with PCR and 5 samples (2.78%) with conventional methods. All samples with positive cultures were also positive by PCR.
Conclusion: The results of this study showed that PCR has a high sensitivity and accuracy for the detection of Nocardia compared with culture and biochemical tests. Considering the rapidity, precision, high sensitivity and specificity of molecular techniques, use of these techniques is suggested in conjunction with conventional methods for the detection of Nocardia phenotypes in clinical laboratories and research centers.