ABSTRACT
Background: Elimination of kala azar from India is challenging as there are potential reservoirs of Leishmania donovani in patients with post-kala-azar dermal leishmaniasis (PKDL). The vast repertoire of carbohydrate moieties on L. donovani is known to elicit specific and strong humoral responses in patients with kala azar. Aim: The present study was undertaken to evaluate the diagnostic performances of anti-gal antibodies using enzyme-linked immunosorbent assay for successful serological diagnosis of PKDL in Indian patients and to differentiate cases of past cured visceral leishmaniasis infections. Methods: We developed Gal enzyme-linked immunosorbent assay to measure specific anti-gal IgG isotype in the sera of 71 Indian patients with PKDL. The diagnostic efficacy of the newly developed assay was evaluated for precision, sensitivity and accuracy. Results: Gal2 enzyme-linked immunosorbent assay revealed three-fold increased anti-gal titers in 71 patients with active PKDL compared to controls. Subclass enzyme-linked immunosorbent assay analysis further revealed enhanced IgG2 and IgG3 anti-gal titers in patients with PKDL compared to control subjects. The rank order for specificity and sensitivity for IgG subclasses was IgG3>IgG2>IgG4>IgG1. The area under the curve values of 0.98 and 0.99 were obtained for IgG and IgG3 Gal2 enzyme-linked immunosorbent assays respectively. Overall sensitivity and specificity were 95.7% (95% CI: 88.1–99.1) and 98.1% (95% confidence interval: 90.1–99.9), and 98.5% (95% CI: 92.4–99.9) and 98.1% (95% CI: 90.1–99.9), respectively. Intra-assay coefficient of variation was 1.5% and inter-assay coefficient of variation was 11.7%. Limitations: The Gal2 enzyme-linked immunosorbent assay needs to be further investigated in mass surveys. Conclusion: Taken together, anti-gal titers detected through Gal2 enzyme-linked immunosorbent assay can serve as an effective diagnostic tool in disease elimination setting and help in better case management in endemic districts.
ABSTRACT
Here we report two cases of anhidrotic ectodermal dysplasia in a family presented to us with intermittent fever, developmental delay, frontal bossing, hypohydrosis, sparse hair and oligodontia. Ectodermal dysplasias are a large hereditary group of disorders which are usually manifested as X-linked recessive hypohidrotic ectodermal dysplasia (HED) and has a full expression in males, whereas females show little to no signs of the disorder. Ectodermal dysplasia are group of rare genetic disorders characterized by faulty development of ectodermal structures and thought to be due to embryonic defect in ectodermal development. Patients frequently consult dentists for delay in tooth eruption so the appropriate awareness of the disease among dentists is essential for early diagnosis.
ABSTRACT
Here, we investigated the quantitative and qualitative differences in antibody classes and subclasses in serum immune complexes (ICs) of Visceral Leishmaniasis (VL), Post Kala-azar Dermal Leishmaniasis (PKDL) and different cross reactive diseases like Malaria, Leprosy, Vitiligo as compared to control subjects. IC levels were measured through a newly developed PEG ELISA, using L. donovani promastigote membrane antigen coated plate. Antibody classes and subclasses were identified using polyspecific sera and monoclonal antibodies, respectively. ICs were purified using polyethylene glycol (PEG) precipitation. Conditional logistic regression showed an association between IgG1-containing ICs and increased risk of PKDL (OR=75, P <0.05) and an association of IgG-containing ICs with VL (OR=621, P=0.001). PEG ELISA demonstrated almost 13-15 fold higher IgG containing ICs titers in VL as compared to control (P <0.001). The assay further established a significant (P <0.05) difference in the IgG containing ICs titers between VL and PKDL. The isolated ICs were further analyzed by subjecting them to one-dimensional PAGE and subsequently stained with combination of periodic acid schiff (PAS) with silver. A differential banding pattern between VL and PKDL was obtained. Four distinct bands with carbohydrate rich glycoconjugates were identified in PKDL ICs, which were absent in VL and control group. It suggests the scope for developing a novel differential diagnostic assay.