Rapid diagnosis of cutaneous leishmaniosis using antibody-conjugated gold Nanoparticles in comparison with molecular and parasitological methods

Abstract

Background Cutaneous leishmaniosis with a broad spectrum of clinical manifestations is caused by the Leishmania parasites. For laboratory diagnosis using parasitological methods, patients’lesion biopsies are either examined under the microscope following appropriate staining or culture in a relevant medium. Although these methods are effective in the early stages of infection, they don’t yield enough sensitivity in chronic cases. Molecular methods usually have a high level of sensitivity and specificity but with the need for lab equipment, they are not suitable for field diagnosis. So, it is important to develop a rapid and point-of-care test to diagnose cutaneous leishmaniasis. Method In this work a lateral flow test for diagnosis of cutaneous leishmaniosis was developed. For evaluation of the test, thirty-eight patient samples with a clinical suggestion of CL were collected and examined using direct microscopy, culture, and PCR and then with the developed lateral flow test. Results Considering Microscopic examination, 28 out of 38 samples were positive and 10 out of 38 were negative. From 28 positive samples, 24, 26, and 26 became positive by cultivation, PCR, and lateral flow test respectively. From negative samples, 1 was positive with the lateral flow test. Considering microscopic results as the gold standard, the sensitivity of %92, %92, and %85 was estimated for lateral flow, molecular, and culture methods respectively. Conclusion The lateral flow test is a very rapid and easy test for diagnosis of cutaneous leishmaniosis especially in rural areas with fewer lab facilities.