Validation of LAMP-LFD Ehrlichia canis DNA sensor Kit

Abstract

Diagnosis of Canine Monocytic Ehrlichiosis is in light of anamesis, visualized cytoplasmic morulae, clinical signs and laboratory test result of platelet counts. The PCR technique is always a definitive confirmatory test of Ehrlichia canis infection. However, the drawback of PCRs test is crucially needed of laboratory equipments. This drawback is somehow enabled newly DNA based technology to be developed in order to eliminate laborious thermocycler and gel electrophoresis. The LAMP-LFD is on focus by using a single temperature to amplify DNA and no gel electrophoresis involved to detect DNA product. LAMP-LFD is included in DNAsensor test kit that recently developed to replace the special equipment requirement for PCRs. This work is aimed to validate LAMP-LFD against nested PCR and single PCR. The validation results showed that nPCR, LAMP-LFD and sPCR are equally in specificity test meanwhile, they have different degrees of sensitivity. nPCR is determined to be the most sensitive method. However, sensitivity of LAMP-LFD and sPCR when compare to nPCR are 78.57% (95% CI= 63.19%-89.70%) and 40.48% (95% CI 25.63% to 56.72%) respectively. The Cohen’s kappa coefficient revealed that nPCR and LAMP-LFD is in substantial agreement (0.785, 89.28% observed agreement) but not sPCR. The application of LAMP-LFD is hence capable of being an alternative method of molecular diagnostic test for CME and a point-of-veterinary care device.