Role of recombinant kinetoplast 39 immunochromatographic test for diagnosis of post kala-azar dermal leishmaniasis
Abstract
Background: Post kala-azar dermal leishmaniasis (PKDL) is a sequel of visceral leishmaniasis (VL) and PKDL
patients are an important reservoir for anthroponotic transmission of VL. Therefore, diagnosis and treatment of PKDL is
important for the kala-azar elimination program in South Asia, including Bangladesh. While definitive diagnosis of
PKDL is still based on microscopy, despite the low sensitivity of this method of diagnosis. Recombinant kinetoplast 39
Immunochromatographic test (rK39 ICT) for detection of kinctoplast antibody against Leishmania parasites from blood
is expected to be a rapid and sensitive diagnostic method. Objective: To sce the efficacy of rapid diagnostic test of
1K39-based ICT in comparison with skin biopsy specimens for LD body detection in PKDL cases endemic area.
Mathodology: This cross sectional comparative study will explore the rapid sensitive method for diagnosis of PKDL.
Both skin biopsy specimens and blood samples were collected from 91 patients suspected to have PKDL from six
upozilla health complexes in Mymensingh district, Bangladesh. After smear preparation and staining LD bodies were
detected from skin biopsy and antibody ware detected from blood by using rK39 ICT method. For all the statistical
analysis p<0.05 was considered as significant. Result: Using microscopy, we identified 57 samples (62.6%) that were
positive for Leishmania. rk39-based ICT indicated that 85 samples (93.4%) were positive for Leishmanial antibody
which were statistically significant. Conclusion: rK39-based ICT for detection of antibody from blood is the most
sensitive and easier method for diagnosis of Post Kala-Azar Dermal Leishmaniasis patients from an endemic area of
Bangladesh.
Keywords
Recombinant kinetoplast 39 ICT
Leishman Donovan body
PKDL
Introduction
Kala-azar or visceral leishmaniasis (VL) is a symptomatic infection of the liver, spleen, and bone marrow that is caused by Leishmania donovani complex, L.donovani, L. infantum (syn. L. chagasi). Leishmania currently infects about 12 million people in $8 countries, causing approximately 57.000 deaths annually. with 350 million individuals at risk. More than 90% of all VL cases are from India, Nepal, Bangladesh, southern Sudan, and northeast Brazil. In Bangladesh, the highest number of VL cases was recorded in the district of Mymensingh, where the average annual incidence rate between 1994 and 2004 was 5.8/10.000; currently. the incidence rate is as high as 300/10.000 in the most affected communities®. Post kala-azar dermal leishmaniasis (PKDL) is a complication or sequel of VL and occurs in nearly 10-20% of patients who have been cured of VL in India and approximately 50-56% of such patients in Sudan®. In India, the disease occurs 1-20 years after recovery from VL. In contrast, in Sudan, PKDL most often develops during treatment or within months afier completion of VL treatment and the symptoms may persist for decades in some patients. Clinically, the condition is characterized by the appearance of macules, papules, or nodules in the skin®. Affected persons, though clinically well, harbor the Leishmania parasite in their skin lesions, and thus become an important reservoir in anthroponotic transmission of leishmaniasis”. Although PKDL has been commonly diagnosed by microscopy. the sensitivity of this technique is low due to the very low number of parasites in slit skin smears and skin biopsy specimens. So, aim of this study is to find out rapid and most sensitive method for diagnosis of PKDL cases.