Serologic follow-up of IgG responses against recombinant mycobacterial proteins ML0405, ML2331 and LID-1 in a leprosy hyperendemic area in Venezuela.

Leprosy is a slowly evolving disease that occurs mainly in adults. In this study, the Mamaría Village, state of Portuguesa was selected because it had one of the highest prevalence rates (13.25%) of leprosy cases in 1997.

Cojedes: a leprosy hyperendemic state.

Background: Leprosy is a chronic infectious disease produced by Mycobacterium leprae. In 1997 Venezuela reached the goal of elimination of leprosy as a public health problem (according to the World Health Organization a prevalence rate of ≤ 1/10,000 inhabitants), but five states still had prevalence rates over that goal. For this study we selected Cojedes State, where prevalence rates remain over the elimination goal.

Molecular drug susceptibility testing and genotyping of Mycobacterium leprae strains from South America.

Possible drug resistance in Mycobacterium leprae strains from Venezuela and three other South American countries was surveyed by molecular methods. None of the 230 strains from new leprosy cases exhibited drug resistance-associated mutations. However, two of the three strains from relapsed cases contained dapsone resistance mutations, and one strain also harbored a rifampin resistance mutation.

[Serological and cellular reactivity to mycobacterial proteins in Hansen's disease].

The study was designed for evaluating immunological reactivity to various mycobacterial protein preparations using serological and cell-mediated immunological tests in patients with clinical leprosy signs, predominantly, with the multibacillary forms. All patients were adults with ages between 20 and 30 years. Fifty eight (n = 81) percent corresponded to Lepromatous Leprosy (LL), 29% (n = 41) to Borderline Lepromatous Leprosy (BL) and 10% (n = 41) to Borderline Borderline Leprosy (BB); only 3% were Borderline Tuberculoid (BT) patients: 74% males and 26% females.

[Immune response of Hansen's disease. Review].

Hansen's disease presents a wide spectrum of clinical and histopathological manifestations that reflect the nature of the immunological response of the host towards diverse Mycobacterium leprae components. The immunological system, composed by both innate and adaptive immunology, offers protection towards infections of various etiologies, among them bacterial. Bacteria, of course, have developed multiple strategies for evading host defenses, based on either very complex or simple mechanisms, but with a single purpose: to "resist" host attacks and to be able to survive.

[Some immunological aspects in the reaccional states of Hansen disease].

The crucial clinical problem in leprosy is represented by episodes of intense inflammation that produce nerve damage. When Mycobacterium leprae has been eliminated by means of antibiotics, the death of the bacteria is not a complete solution to the damage caused in nerves. Two of the more frequent immunopathological phenomena in Hansen's disease are Type I, reactions, known as Reversal Reactions (RR), and Type II reactions, of which the most frequent and well known are those called Erythema Nodosum Leprosum (ENL).

[Increase in nitric oxide concentrations in serum and mononuclear cell cultures from patients with Type II reaction state of Hansen's disease].

The word "reaction" is used in leprosy to describe signs and symptoms of acute inflammation. Type II reactions, including erythema nodosum leprosum (ENL) occur in the multibacillary forms of Hansen's disease. Nitric oxide (NO) could play a role in the response of the host, where a high NO production would be involved in acute inflammatory processes.