Loop-mediated Isothermal Amplification Test for Rapid Identification of Clinical Nocardia Isolates

Jundishapur Journal of Microbiology

article

Mojtaba Taghizadeh Armaki¹  Mohammad Hossein Tayefeh-Arbab¹  Jalal Jafarzadeh²  Sina Nasrollahian³  Zohre Baseri⁴  Hamed Mehdinezhad⁵  Ramazan Rajabnia¹  Abazar Pournajaf¹ 

[1] Infectious Diseases and Tropical Medicine Research Center, Health Research Institute, Babol University of Medical Sciences;Department of Parasitology and Mycology, Faculty of Medicine, Babol University of Medical Sciences;Department of Bacteriology and Virology, School of Medicine, Shiraz University of Medical Sciences;Department of Pathology and Laboratory Medicine, Shariati Hospital, Tehran University of Medical Sciences;Department of Internal Medicine, Rouhani Hospital, School of Medicine, Babol University of Medical Sciences

关键词: Loop-mediated Isothermal Amplification Test;    Nocardia;    Clinical Sample;    Rapid Detection;   

DOI  :  10.5812/jjm-132432

学科分类：微生物学和免疫学

来源: Jundishapur Journal of Microbiology

【 摘 要 】

Background: Nocardia is a Gram-positive and partially acid-fast bacterium. The species are widely distributed in the environment and cause severe human infections. Nocardiosis is not easily identifiable due to the lack of pathognomonic clinical signs. Objectives: The present study was designed to develop and evaluate a simple and quick method based on a loop-mediated isothermal amplification (LAMP) assay for detecting Nocardia spp isolated from bronchoalveolar lavage (BAL) samples. Methods: In this cross-sectional study, 357 BAL samples were collected from two teaching hospitals. The polymerase chain reaction (PCR) was performed using a set of species-specific primers for the 16S rRNA gene. Kinyoun acid-fast staining and culture were done on the Sabouraud dextrose plate. The optimal LAMP reaction condition was set at 65°C for 45 min, with the recognition limit as 1 pg DNA/tube and 100 CFU/reaction. In addition to calcein and manganous ions, agarose gel electrophoresis was used to visualize the amplified LAMP products. Results: Out of 357 BAL samples, 0 (0.0%), 4 (1.1%), 9 (2.5%), and 10 (2.8%) Nocardia strains were identified by direct staining of partial acid-fast, streak culture plate, PCR, and LAMP methods, respectively. Conclusions: We developed a new LAMP technique for the recognition of Nocardia, which is fast, very precise, simple, and low-cost. According to our knowledge, this is the first report of the LAMP method to detect Nocardia in clinical samples.

【 授权许可】

CC BY-NC