Evaluation of four rapid diagnostic tests for canine and human visceral Leishmaniasis in Colombia

Abstract

Background Leishmaniasis caused by different species of Leishmania affect 98 countries worldwide. Visceral Leishmaniasis (VL) is the mortal clinical presentation of the disease that causes the dead to more than 90% of the patients who suffer it. The diagnosis of VL is made by the direct observation of the parasite in bone marrow, spleen and/or liver aspirates that requires complex proceedings. Therefore, serum samples are submitted to Indirect Immunofluorescence to identify the presence of anti- Leishmania antibodies. Despite the variability in the diagnostic performance of the Immunochromatographic Tests (ICTs), there are many evidences that suggest that ICTs can be used for epidemiological screening. However, in Colombia there are not any evidence about the performance of the ICTs for VL diagnosis , both for human and canine serum samples. Therefore, this study evaluated the diagnostic performance of 4 ICTs for VL (2 ICTs in human sera and 2 ICTs in canine sera) in samples from endemic areas of Colombia. Methods We selected a total of 156 human serum samples (82 positive and 74 negative for VL) and 126 canine serum samples (71 positive and 54 negative) diagnosed by in house Indirect Immunofluorescence (IIF). The samples were submitted to the ICTs following the manufacturers’ instructions. Statistical analysis was performed to evaluate the diagnostic performance of each ICT in comparison with the IIF. PCR for HSP70 gene and sanger sequencing was performed in samples with negative results for both ICTs. Results The sensitivity (S) of both ICTs for human samples (Ad-bio Leishmania IgG/IgM Combo Rapid Test and Kalazar Detect™) was 91.5% and specificity (E) were 93.2 and 89.2% respectively, while for the ICTs tested on canine samples (Kalazar Detect™ Rapid Test, Canine and DPP® CVL rapid test) we found S values between 82.9 and 85.7% and E values between 79.6 and 92.6%. We found L. infantum by PCR and sequencing in 2 human samples, and L. braziliensis and L. amazonensis in canine serum samples that were negative by both ICTs. Conclusions We conclude that both tests evaluated on human samples have a similar diagnostic performance, while the Kalazar Detect™ Rapid Test, Canine showed a better diagnostic performance than the DPP® CVL rapid test evaluated on canine samples. Also, we suggest that it is necessary to design tests with antigens of the circulating strains to increase its diagnostic utility.

Complex ecological interactions across a focus of cutaneous leishmaniasis in Eastern Colombia: novel description of Leishmania species, hosts and phlebotomine fauna

“…Cows, canines and horses were also found to participate in transmission, and their roles in transmission dynamics are likely to be highly relevant given their proximity to humans. The infection of canines in Colombia with various Leishmania species has been described previously [ 9 , 12 , 60 ]; clearly, they have important roles in Leishmania transmission dynamics. However, it is not apparent if they act as barriers, preventing infection in humans (dilution effect), or if they act as reservoirs or sources of the parasite [ 60 , 61 ].…”

“…The infection of canines in Colombia with various Leishmania species has been described previously [ 9 , 12 , 60 ]; clearly, they have important roles in Leishmania transmission dynamics. However, it is not apparent if they act as barriers, preventing infection in humans (dilution effect), or if they act as reservoirs or sources of the parasite [ 60 , 61 ]. The detection of blood from cows, horses and pigs is also very important, especially with regard to the roles they play in the domestic environment, their mobility between localities and environments, and their proximity to humans.…”

Prognostic Factors and Life Expectancy in Canine Leishmaniosis

“…In twenty dogs, the results of qualitative RIT tests were not confirmed by quantitative serological tests due to economic restrictions. Although RIT based assays are easy to use and provide rapid results, the performance is still not optimal [ 25 , 64 , 65 ]. Furthermore, in these cases, failure to determine the level of antibodies compromises continued patient management.…”

Recuperating Biopharmaceutical Aspects of Amphotericin B and Paromomycin Using a Chitosan Functionalized Nanocarrier via Oral Route for Enhanced Anti-leishmanial Activity

“…Visceral leishmaniasis (VL), also known as kala-azar is a vector-borne infectious disease caused by an obligate intracellular protozoan parasite of Leishmania species and invades the reticuloendothelial system of spleen, liver, and bone marrow (Chappuis et al, 2007 ; Shrestha et al, 2018 ; Herrera et al, 2019 ; Martínez and Ruiz, 2019 ). VL is a serious public health issue in many tropical and subtropical regions of the globe and affects poor and malnourished people in developing and underdeveloped countries of Brazil, East Africa, and South-East Asia.…”

“…VL is a serious public health issue in many tropical and subtropical regions of the globe and affects poor and malnourished people in developing and underdeveloped countries of Brazil, East Africa, and South-East Asia. VL is the most severe form of leishmaniasis, characterized by irregular bouts of fever, anemia, weight loss, hepatosplenomegaly, and is fatal if untreated (Sundar and Singh, 2016 ; Herrera et al, 2019 ). According to World Health Organization (WHO), 50,000–90,000 new VL cases reported globally and more than 95% of new VL cases reported in 10 countries: Bangladesh, Brazil, China, Ethiopia, India, Kenya, Nepal, Somalia, South Sudan, and Sudan.…”