OPTIMIZATION OF A METHOD OF ISOTHERMAL AMPLIFICATION (LAMP) FOR DIAGNOSIS OF WHOOPING COUGH

Abstract

Aim. Optimization of the accelerated whooping cough method of isothermal amplification for DNA Bordetela pertussis. Materials and methods. The research was conducted on 35 standard collection strains and 169 strains of Bordetella allocated in bacteriological laboratories of territorial subjects of the Russian Federation. The research included 329 clinical samples received from patients with whooping cough and the persons, contact with them, hospitalized in IDCH No. 1 DZM. Chromosomal DNA was extracted with a standard method of boiling from strains, from clinical samples by means of commercial sets. Identification of causative agents of whooping cough were performed with use of the АмплиСенс® Bordetella multi-FL. Results. We performed optimization method of a diagnostics of whooping cough by LAMP with detection by means of an electrophoresis and with naked-eye inspection under normal light is developed. The developed method allows to detect a DNA of B.pertussis within 4 - 5 hours in clinical material. The analytical sensitivity was 102 GE/ml. Assessment of validity showed that the developed method possesses 99,6% sensitivity and 98,7% specificity; predictive value positiveness and negative result was 99,6% and 98,7%, respectively; the index of accuracy (diagnostic efficiency) - 99,4%; the likelihood ratio of positive and negative result - 76,6 and 0,004, respectively. Assessment of analytical reliability in 100% of cases showed convergence and reproducibility of a technique. Conclusion. Diagnostic test on DNA of B.pertussis identification by LAMP method will allow to increase efficiency of laboratory diagnosis of whooping cough.