The Leishmania IgG/IgM Combo Rapid Test is a lateral flow immunoassay for the simultaneous detection and differentiation of IgG and IgM to the subspecies of the Leishmania donovani (L. donovani), the Visceral leishmaniasis causative protozoans, in human serum, plasma, or whole blood. It is intended to be used as a screening test and as an aid in the diagnosis of the disease of Visceral leishmaniasis. Any reactive specimen with the Leishmania IgG/IgM Combo Rapid Test must be confirmed with alternative testing method(s).
Visceral leishmaniasis, or Kala-azar, is a disseminated infection caused by several subspecies of the L. donovani. The disease is estimated by the World Health Organization (WHO) to affect approximately 12 million people in 88 countries 1. It is transmitted to humans by bites of the Phlebotomus sandflies, which acquire infection from feeding on infected animals. Though it is a disease found in poor countries, in Southern Europe, it has become the leading opportunistic infection in AIDS patients2-3. Identification of L. donovani organism from the blood, bone marrow, liver, lymph nodes or the spleen provides a definite mean of diagnosis. Serological detection of anti-L. donovani IgM is found to be an excellent marker for the acute Visceral leishmaniasis. Tests used in clinics include ELISA, fluorescent antibody or direct agglutination tests 4-5. Recently, utilization of L. donovani specific protein in the test has improved the sensitivity and specificity dramatically6-7. The Leishmania IgG/IgM Combo Rapid Test is a recombinant rK39 based serological test, which detects IgG and IgM antibodies to the L. Donovani simultaneously. The test provides a reliable result within 15 minutes without any instruments.
The Leishmania IgG/IgM Combo Rapid Test is a lateral flow chromatographic immunoassay. The test cassette consists of 1) a burgundy colored conjugate pad containing recombinant rK39 antigen conjugated with colloid gold (Leishmania conjugates) and rabbit IgG-gold conjugates, 2) a nitrocellulose membrane strip containing two test bands (M and G bands) and a control band (C band). The M band is pre-coated with monoclonal antihuman IgM for the detection of anti-L. donovani IgM, G band is pre-coated with reagents for the detection of anti-L. donovani IgG, and the C band is pre-coated with goat anti rabbit IgG.