Immunologic aspects of leprosy with reference to extravascular immunoglobulins: their excretion profile in urine

An aliquot of 24-hour urine collected from leprosy patients was concentrated and examined for the presence of albumin, transferrin, IgG, IgA, IgM, IgD, D3, kappa and lambda light chains by the gel diffusion technic using respective monospecific antisera. Urinary protein excretion profile in lepromatous leprosy patients showed that while excretion of transferrin in the urine was negligible; that of IgG molecules, a substance of higher molecular weight, was significant. It is suggested that the immunoglobulins excreted in the urine may not be plasma-derived, but extravascular in origin. They are probably synthesized in the urinary tract. In the present study, out of 25 leprosy patients, 2 female patients having severe lepra reactions developed urinary tract infections. E. coli and Klebsiella were isolated from their urine. The urinary IgG levels in those two cases were found to be the highest in the series.