Comparative evaluation of immunochromatographic dipstick test (ICT) rk39, soluble antigen ELISA and IFAT for the sero-diagnosis of visceral leishmaniasis in Morocco

• Published in: Acta tropica Vol. 182; pp. 185 - 189
• Main Authors: Mniouil, Meryem, Fellah, Hajiba, Amarir, Fatima, Sadak, Abderrahim, Et-touys, Abdeslam, Bakri, Youssef, Moustachi, Aziza, Tassou, Fatima Zahraa, Hida, Mostapha, Lyagoubi, Mohamed, Adlaoui, El Bachir, Rhajaoui, Mohamed, Sebti, Faiza
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.06.2018
• Subjects: Adolescent; Antigens, Protozoan - analysis; Child; Child, Preschool; Diagnosis; Enzyme-Linked Immunosorbent Assay - methods; Female; Fluorescent Antibody Technique - methods; Humans; Immunochomatographic dipstick test rk39; Immunochromatography - methods; L. infantum; Leishmania infantum - immunology; Leishmaniasis, Visceral - diagnosis; Male; Morocco; Polymerase Chain Reaction; Sensitivity; Serologic Tests; Specificity; Visceral leishmaniasis; Sensitivity; Specificity; Immunochomatographic dipstick test rk39; Morocco; Visceral leishmaniasis; L. infantum; Diagnosis
• ISSN: 0001-706X; 1873-6254
• DOI: 10.1016/j.actatropica.2018.03.007

The aim of this study was to evaluate for the first time in Morocco the sensitivity and specificity of “rK39 Kalazar Detect TM Rapid Test” strips to determine whether these kits conformed to the standard set by the human VL elimination program in Morocco. The sensitivity and the Specificity of ICT rk39 was 95.8% and 100%, respectively. [Display omitted] •A total of 49 admitted patients with strong clinical suspicion of VL and 40 healthy controls were investigated for the performance of the ICT rk39.•The ICT rK39 was positive in 23 (46, 9%) of the 24 patients with VL, 25 of the 26 negative sera were from children and one was from an adult patient.•The sensitivity of ICT rk39 and IFAT was calculated at 95.8% and 87.5%, respectively. A rapid, sensitive and specific tool for detection of Leishmania infantum infection in Humans would be highly desirable, because it would allow control interventions in endemic areas of visceral leishmaniasis. This study was carried out at the Reference National Laboratory of Leishmaniasis (RNLL) in National Institute of Hygiene (NIH) Morocco, in order to evaluate the diagnostic potential of immunochromatographic dipstick test (ICT) rk39 in Moroccan suspected VL patients. A total of 49 admitted patients with strong clinical suspicion of VL and 40 healthy controls were investigated for the performance of the ICT rk39. Bone marrow smears were examined for microscopic detection of Leishmania amastigotes obtained from the admitted patients. Only PCR and smear positive cases were considered as gold standard as well as confirmed cases of VL. Out of 49 suspected patients, twenty four (48.9%) were found PCR and smear-positive and twenty three (46.9%) were positive for ICT rk39. Voluntary healthy controls, which included twenty persons from the endemic zone and twenty from non-endemic zone of VL, were found all negative for the strip test. The sensitivity in sera was 75% by ELISA and 87.5% by IFAT, compared with 95.8% for ICT rk39. Specificity was 95.8%, with both tests ELISA and IFAT, and 100% by ICT rk39 respectively. Present study findings again reinforce that the ICT rk39 is a simple, reliable and easy-to-perform non-invasive diagnostic tool for visceral leishmaniasis in the endemic area of Morocco.