LOOP-MEDIATED ISOTHERMAL AMPLIFICATION (LAMP): SENSITIVE AND RAPID DETECTION OF SCHISTOSOMA HAEMATOBIUM DNA IN URINE SAMPLES OF EGYPTIAN SUSPECTED CASES.

Document Type : Original Article

Authors

1 Medical Parasitology, Faculty of Medicine, Cairo University, Egypt.

2 Molecular Biology, Medical Research Center, Faculty of Medicine, Ain Shams University, Egypt.

3 Theodore Bilharz Research Institute, Egypt.

Abstract

Schistosomiasis haematobium is a major endemic parasitic disease in many tropical regions including Egypt. Typical infection results in haematuria, dysuria, anaemia, genital as well as urinary tract lesions, with prospect of kidney damage in complicated cases. In addition, deposited eggs in the tissue, eventually leads to squamous cell carcinoma of urinary bladder in chronically infected individuals. Microscopic detection of excreted ova in urine samples remains the gold standard diagnostic method, in spite of its inherited low sensitivity, inconsistent egg excretion and unreliable results in chronic phase of the disease. Moreover due to pre-requisite for skilled personals and pricey equipment, PCR-based technologies are of limited use especially in low-income endemic countries. So emergence of loop-mediated isothermal DNA amplification (LAMP) seemed a promising technique. Our study evaluated application of LAMP technique in detection of S. haematobium DNA in 69 urine samples of suspected patients for urogenital schistosomiasis, versus conventional urine filtration followed by microscopy ova detection method. Specificity of LAMP was tested using other parasites DNA samples that showed no cross reactivity. Furthermore our results of the calculated diagnostic parameters for sensitivity and specificity for LAMP assay were 100%, with 95% CI (88.78%-100%), and 63.16%, with 95% CI (45.99%-78.19%) respectively, moreover Positive likelihood ratio (LR+) 2.7, and Negative likelihood ratio (LR-) 0.0, which display that LAMP
technique is an up-to-date simple, sensitive, diagnostic important tool that could be employed in clinical diagnosis in poorly equipped facilities, as well as in surveillance of infectious diseases. As authors knowledge, this is the first national report evaluation of LAMP technique as a promising diagnostic tool for urogenital schistosomiasis.

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