[ identification of nocardia in BAL specimens of bronchoscopic patients by using classical and molecular methods]

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. 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. 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. 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

Isolation of Candida species from the bronchoalveolar tavage in patients with pulmonary diseases

Definite diagnosis of Candida pneumonia remains a problem in medicine. Although, isolation of'Candida spp. from the bronchoalveolar lavage is not diagnostic by itself, it may be helpful in early diagnosis of pulmonary candidiasis in immunocompromised or critically ill patients and prompt antifungal therapy. In a cross- sectional study, bronchoalveolar lavage was obtained from 144 patients with pulmonary diseases and different predisposing factors. All specimens were examined by direct microscopy and inoculated on CHOROM agar Candida plates. Corn-meal agar medium and API 20C diagnostic kit also were used for identification of different stains of'Candida. Candida spp. was isolated from 74 [51.3%] specimens. The most common isolated species was Candida albicans with frequency of 69.7%, followed by C.glabrata [20.2%], C.kefyr [5.6%], C.krusei [2.25] and C.tropicalis [1.2%]. Hypercolonization [>/= 10[3] CFU/mL] was found in 10 patients. This report implies the high frequency [30.3%] of non- albicans Candida spp. isolated from respiratory tract, necessity the application of other diagnostic methods and following up the patients. Less susceptibility ofnon- albicans Candida spp. to present anti- fungal drugs must be noted and hypercolonization of respiratory tract with Candida spp. should be considered as a initiating factor for invasive candidiasis