Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “LEPROSY”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,765 records · Page 98Linked to original sources
PubMed1996

Detection of transforming growth factor-beta 1 in dermal lesions of different clinical forms of leprosy.

Immunohistochemical studies were performed to determine the presence and distribution of polypeptide transforming growth factor (TGF)-beta 1, a cytokine with macrophage-suppressing activity, in skin biopsies from 41 patients with different clinical forms of leprosy. We used an anti-TGF-beta 1 polyclonal antibody and the avidinbiotin-peroxidase (ABC complex) method. The results demonstrated that the lesions of the lepromatous and borderline lepromatous forms presented intense cytoplasm staining for TGF-beta 1 in the cells of the dermal infiltrate. A reaction of moderate intensity was observed in the cells of granulomas from borderline borderline cases, whereas no detectable immunoreaction was observed in granuloma cells from the tuberculoid and borderline tuberculoid forms. Considering that in the lepromatous leprosy form Mycobacterium leprae multiplies in the cytoplasm of macrophages and the lesions are diffuse and consist of poorly differentiated young macrophages, we believe that these alternations may be explained at least in part by the presence of TGF-beta 1 in the dermal infiltrate. Production of the cytokine may be induced by the presence of the bacillus itself and of its constituents, causing a mechanism of parasite evasion. Similarly, the absence of TGF-beta 1 in tuberculoid leprosy, which progresses with a specific immune response to M. leprae, may explain the intense differentiation of macrophage cells with the formation of well defined epithelioid granulomas capable of eliminating most of the bacilli.

Biopsy↗
PubMed1996

Silent iritis in treated bacillary negative leprosy.

Iridectomy specimens from 59 leprosy patients who had adequate medical records of whom 33 belong to the lepromatous (LL) leprosy variety and 16 normal controls were studied histopathologically. All patients were bacteriologically negative and had received dapsone followed by multidrug therapy (MDT), or MDT only, or only dapsone for varying periods. It was found that leprosy, particularly lepromatous disease, did not significantly decrease the age of formation of cataract. Of the 33 LL patients studied 60.6% had silent iritis. The duration of treatment had no obvious influence on the persistence of iritis. Treatment with only 2 years of MDT for LL patients did not significantly increase the prevalence of persistent silent iritis compared to those who received other types of antileprosy therapy for long periods. It is pointed out that chronic iritis is a serious complication that continues even after the patient is declared clinically and bacteriologically cured, especially in patients who had a history of chronic iritis clinically.

Aged↗
PubMedDate not supplied

Leprosy among inmates of a prison.

A leprosy survey carried out in a district prison revealed a gross prevalence of 20 cases per 1000, and active prevalence of 10 cases per 1000 whereas, prevalence of leprosy in the state was 1.12 per 1000. Such prisons thus form hyperendemic pockets. The inmates are a closed community and there is a risk of cases among inmates spreading infection to others inside the prison during their sojourn there and to the community when they are released from the prison. Special efforts are required to identify and eliminate all identifiable sources of infection, especially at this point of time when we are aiming at elimination of leprosy as a public health problem.

Humans↗
PubMed2003

Citrus leprosis virus vectored by Brevipalpus phoenicis (Acari: Tenuipalpidae) on citrus in Brazil.

Citrus leprosis is caused by Citrus leprosis virus (CiLV) that is transmitted by mites in the genus Brevipalpus (Acari: Tenuipalpidae). This disease directly reduces production and the life span of the citrus plant. The main symptoms of the disease include lesions on fruits, leaves, and twigs or small branches, causing premature fruit drop, defoliation, and death of the twigs or branches leading to serious tree decline. Leprosis is a highly destructive disease of citrus, wherever it occurs. The Brazilian citrus industry spends over 100 million US dollars annually on acaricides to control the vector, Brevipalpus phoenicis (Geijskes). This review contains information about the history of the etiology of citrus leprosis, its geographical distribution, host range, the role of the mite vectors, viral morphology and relationships with the infected cell, and transmissibility of the virus by the mite. In addition, data on the mite-virus-plant relationship, disease damage, and strategies for controlling disease spread are presented.

Animals↗
PubMed1988

Measurement of hypoxanthine incorporation in purified suspensions of Mycobacterium leprae: a suitable method to screen for anti-leprosy agents in vitro.

The rate of incorporation of hypoxanthine was measured in suspensions of Mycobacterium leprae, with and without added anti-leprosy agents. Dapsone, clofazamine and brodimoprim, as well as other benzylpryimidines, inhibited hypoxanthine incorporation, and their minimum inhibitory concentrations for incorporation with intact M. leprae were near the minimum inhibitory concentrations at which the agents have antibacterial effects. At sub-inhibitory concentrations for hypoxanthine incorporation, some combinations of benzylpyrimidines and dapsone were inhibitory, suggesting that synergic effects of anti-leprosy agents might also be detected by the inhibition of hypoxanthine incorporation. Thus, demonstration of inhibition of hypoxanthine incorporation in M. leprae could be a rapid method for screening anti-leprosy agents and especially for preliminary testing of new, potential anti-leprosy agents. The rate of hypoxanthine incorporation was generally lower in suspensions of M. leprae with lower viability, but it was not proportional to viability so the technique would not be suitable for accurate determination of viability.

Hypoxanthine↗
PubMed1992

Tuberculosis and leprosy: attempts to identify T-cell antigens of potential value for vaccine design.

Tuberculosis and leprosy are chronic bacterial infectious diseases which represent major health problems worldwide. It is generally accepted that, on the one hand, effective vaccination strategies are required for satisfactory control of these diseases and, on the other hand, that currently available vaccination measures are insufficient for this purpose. Ideally, a subunit vaccine should be designed which is composed of one or a few protective antigens. In this brief treatise our approach towards the identification of antigens with potential value for vaccine design is described. It comprises high resolution fractionation by two-dimensional gel electrophoresis, transfer of separated fractions by electroelution and testing of separated fractions with viable T cells and accessory cells. Using this approach we find: (1) multiple antigens are recognized by T cells from leprosy and tuberculosis patients as well as healthy contacts; (2) apparently, suppressive antigens exist in leprosy; (3) an antigen cluster which is apparently indicative for immunity against M. tuberculosis is present among secreted proteins. We hope that further improvement of this methodology will help in the rational design of subunit vaccines against tuberculosis and leprosy.

Antigens, Bacterial↗
PubMed1997

Serodiagnosis of tuberculosis and leprosy by enzyme immunoassay.

OBJECTIVE: To evaluate the use of serodiagnosis for tuberculosis and leprosy using mycobacterial antigen 38 kDa, with kits from Omega laboratories, to detect IgG by enzyme immunoassay (EIA). METHODS: The study population consisted of 58 patients with evidence of tuberculous infection (culture of Mycobacterium tuberculosis complex or microscopic evidence), of whom 23 had pulmonary and 35 had extrapulmonary disease. There were six subjects who had recently been treated for tuberculosis, 11 patients on treatment for leprosy and 137 patients suspected of having tuberculosis on clinical or radiologic grounds (without laboratory evidence). A control group comprised 35 healthy individuals or patients suffering from diseases other than tuberculosis. RESULTS: The tests showed that there was a significant difference in antibody levels between the patients with active pulmonary disease, extrapulmonary tuberculosis and leprosy in comparison with the control group (p<0.001). The sensitivities of the two tests together for proven pulmonary tuberculosis were 100% and 95.7% at 1.0--1.5 and >1.6 EIA cut-off points respectively, while the specificities were 88.5% and 100% at the same cut-off points. The sensitivities for extrapulmonary tuberculosis were 71.4% and only 51.4% at 1.0--1.5 and >1.6 EIA cut-off points. The test was positive in 30 (21.9%) of the 137 suspected patients, while 43 (31.4%) had an equivocal result and the remaining 64 (47.7%) suspects were definitely negative. There was again a significant difference in positivity rates between suspects and the control group. CONCLUSIONS: Omega IgG test is useful in the serodiagnosis of active pulmonary tuberculosis and leprosy, but less sensitive in extrapulmonary disease, particularly in children. Equivocal results may only add to the evidence of tuberculosis in early or minimal disease.

Journal Article↗
PubMed1970

Phenoloxidase activity in organisms isolated from lepromatous and tuberculoid leprosy.

Anaerobic corynebacteria (propionibacteria), isolated in pure culture from the plasma of a case of tuberculoid leprosy and from lepromata of cases of lepromatous leprosy, exhibited phenoloxidase activity such as that shown by Prabhakaran to be associated with leprosy bacilli harvested from patients suffering from leprosy. Several corynebacteria, mycobacteria, and nocardias similarly examined did not produce phenoloxidase.

Journal Article↗
PubMed1970

Some recent laboratory findings on Mycobacterium leprae. Implications for the therapy, epidemiology and control of leprosy.

From changes in the morphology and viability of Mycobacterium leprae in infected mice, some authors have concluded that the majority of smear-positive human lepromatous patients become non-infectious within 3-4 months of the beginning of regular treatment with sulfones, even at dosages equivalent to only one-hundredth of the conventional daily dose-namely, 1 mg daily. These very low dosages have, however, not been advocated because of the risk that resistant strains of Myco. leprae might develop. The laboratory findings have already been applied to human leprosy by some leprologists; if they were more widely adopted, leprosy programmes could be seriously affected and the consequences could be serious in endemic areas. Contrary to the results of laboratory tests, the shortcomings of clinical sulfone therapy are evident all over the world from the long times required for lepromatous cases to become bacteriologically negative, from the high proportion of relapses and from chemoprophylaxis trials in child contacts. Final proof of the relationship between the morphological index, i.e., the proportion of solidly staining bacilli present, and contagiousness can come only from prolonged and well-planned epidemiological studies. It appears that leprosy may develop in appreciable numbers of child contacts exposed to index cases already bacteriologically negative, with or without prophylactic dapsone treatment.The results of controlled BCG trials now in progress are not consistent although laboratory trials in mice have indicated that BCG vaccination confers a high degree of protection. However, the results that have been obtained in the mouse, an unnatural host, may not be obtainable in man.It is considered premature to apply laboratory findings to human leprosy before clinical and epidemiological studies have been made in man.

Animals↗
PubMed1981

Serology of leprosy. II. Demonstration of specific antibodies to mycobacterium leprae by counter current electrophoresis.

A rapid and simple method for the demonstration of specific antibodies to Mycobacterium leprae using counter current electrophoresis (CCE) has been described. Three types of antigens (sonicate antigen, surface antigen and purified protoplasmic protein antigen) were prepared from purified M. leprae and tested against sera from patients with different types of leprosy, and their healthy household contacts, by CCE. Antibodies specific to M. leprae were demonstrated by CCE after absorption of sera with M tuberculosis and M. vaccae. All advanced forms of leprosy (LL and BL) and a lesser number of other forms of leprosy (BB, BT and TT) showed specific antibodies reactive with the three types of soluble antigens from M. leprae and antibodies reactive with soluble antigens from M. tuberculosis and M. vaccae. The latter type of antibodies were however removed by prior absorption of sera with respective mycobacteria. The applicability of the simple electrophoresis method in the serology of leprosy is discussed.

Antibodies, Bacterial↗
PubMedDate not supplied

Two methods of demonstrating leprosy bacilli in smears.

Two methods, the carbol fuchsin with acetic acid differentiation and the periodic acid-carbol pararosaniline, were used for demonstrating leprosy bacilli in skin smears. Bacillary smears from 200 long-treated patients with tuberculoid, borderline and lepromatous leprosy were stained with periodic acid-carbol pararosaniline. There were significantly greater BI and MI determinations than with classic carbol fucsin staining. With the former stain bacilli were found in 69 of 96 skin smears in which no bacilli could be seen by the latter stain. It is suggested that under the action of antileprosy drugs some leprosy bacilli may lose their acid-fastness and become chromophobic; chromophobic bacilli can be restored to their staining with periodic acid pretreatment. Leprosy bacilli in their chromophobic form can survive in healing and apparently healed lesions even after prolonged chemotherapy and can be a possible source of relapse.

Acetates↗
PubMed1998

Alterations in early biochemical events following T cell activation in leprosy patients.

The early events of activation and cytokine profiles (IL-2, 4, and 6) were studied in lymphocytes of paucibacillary (TT/BT) and multibacillary (BL/LL) leprosy patients after stimulation with PMA/A23187 and Mycobacterium leprae antigen (PGL-1). Lymphocytes from BT/TT patients showed proliferation in response to both PMA/A23187 and PGL-1 compared to BL/LL. The levels of early activation signaling molecules such as IP3, calcium, and protein kinase C (PKC) in the particulate fraction were found to be elevated in BT/TT and BL/LL patients and showed a further significant increase after stimulation with PMA/A23187 in BT/TT patients. PGL-1 marginally increased the IP3 levels in BT/TT patients, whereas in BL/LL patients, it had no effect. The levels of IL-2 were enhanced in lymphocytes of BT/TT leprosy patients and were further augmented by PPD and PGL-1, while the levels of IL-4 and IL-6 were increased in LL/BL lymphocytes and further augmented by PGL-1. Thus PGL-1 seems to be a major culprit in inducing the TH2-type cytokine response observed in lepromatous leprosy patients.

Antigens, Bacterial↗
PubMed1992

Immune complexes and antibody levels in blisters over human leprosy skin lesions with or without erythema nodosum leprosum.

Erythema nodosum leprosum (ENL) is a serious complication of lepromatous leprosy, affecting skin and peripheral nerves in a large percentage of these patients, and is presumed to result from spontaneous immunologic changes. Its pathogenesis is poorly understood, although histopathologic features have suggested immune complex (IC)-mediated injury. Abundant circulating antibody is present but no convincing correlation has been established between circulating IC and ENL. We have examined cutaneous leprosy lesions in vivo using blisters induced by prolonged gentle suction to determine whether or not IC are demonstrable in lesions with or without ENL, using an IC assay based on monoclonal rheumatoid factor binding. We also examined whether antibodies involved in such IC are produced locally or reach the skin via the circulation. Surprisingly large quantities of IC were found in ENL lesions, and in some cases the quantities were significantly higher than in matching serum. Total IgG, IgA, and IgM in the skin were not higher than expected, however. Attempts to demonstrate increases in intracutaneous levels of specific anti-Mycobacterium leprae antibodies were unsuccessful. This is the first report of the demonstration of IC in suction blister fluid. The results indicate that large quantities of IC may be present in cutaneous leprosy lesions and are consistent with the hypothesis that they are formed in situ when circulating antibody combines with antigen in the skin. The nature of the antigen in these IC remains undefined.

Antibodies↗
PubMed1991

Risk factors for type-1 reactions in borderline leprosy patients.

Type-1 or reversal reactions are the major cause of nerve damage and disability in leprosy. We wished to determine whether there were any clinical or laboratory markers that identified patients with an increased risk of type-1 reaction. 42 (31%) of 136 Nepalese borderline leprosy patients (97 male, 39 female; age range 7-73 years) had a type-1 reaction during the first 2 years of multi-drug therapy. Before therapy, 41 (98%) of the 42 patients were seropositive for antibodies to one of three mycobacterial antigens. Seropositivity for IgM antiphenolic-glycolipid-1 (PGL-1) antibodies, but not IgG anti-lipoarabinomannan or anti-Mycobacterium leprae 35 kDa protein antibodies, was significantly associated with subsequent manifestation of a type-1 reaction (p less than 0.001). The concentration of IgM anti-PGL-1 antibodies in serum was significantly higher in patients in whom a type-1 reaction developed. The risk attributable to anti-PGL-1 seropositivity was independent of leprosy class, skin smear positivity, and the presence of other anti-M leprae antibodies (adjusted odds ratio = 8.7, p less than 0.001). In the 87 patients who had a lepromin test, anti-PGL-1 seropositivity and lepromin reactivity were significant independent risk factors for subsequent reaction. 78% of patients with positive lepromin reactivity and IgM anti-PGL-1 antibodies had type-1 reactions. Patients with these risk factors should be carefully monitored during antimicrobial therapy to permit early initiation of anti-inflammatory treatment thus minimising permanent nerve damage and resultant disability.

Adolescent↗
PubMed2001

T-cell release of granulysin contributes to host defense in leprosy.

A novel mechanism by which T cells contribute to host defense against microbial pathogens is release of the antimicrobial protein granulysin. We investigated the role of granulysin in human infectious disease using leprosy as a model. Granulysin-expressing T cells were detected in cutaneous leprosy lesions at a six-fold greater frequency in patients with the localized tuberculoid as compared with the disseminated lepromatous form of the disease. In contrast, perforin, a cytolytic molecule that colocalizes with granulysin in cytotoxic granules, was expressed at similar levels across the spectrum of disease. Within leprosy lesions, granulysin colocalized in CD4+ T cells and was expressed in CD4+ T-cell lines derived from skin lesions. These CD4+ T-cell lines lysed targets by the granule exocytosis pathway and reduced the viability of mycobacteria in infected targets. Given the broad antimicrobial spectrum of granulysin, these data provide evidence that T-cell release of granulysin contributes to host defense in human infectious disease.

Anti-Infective Agents↗
PubMed1991

Recombinant fusion protein identified by lepromatous sera mimics native Mycobacterium leprae in T-cell responses across the leprosy spectrum.

Pooled polyvalent sera from lepromatous leprosy patients were used to screen a lambda gt11 recombinant DNA expression library of Mycobacterium leprae in order to identify the relevant antigens recognized by the human immune response. Of the 300,000 phages screened, 4 clones were identified that coded for fusion proteins of the same molecular mass. The fusion protein from clone LSR2 was tested for immunoreactivity in assays using peripheral blood cells and sera from 11 laboratory personnel and 105 patients across the leprosy spectrum. LSR2 protein appears to be predominantly a T-cell antigen. It evokes similar lymphoproliferative responses as the native bacillus both at the individual level and in the leprosy spectrum as a whole. Though only 50% of patient sera with anti-M. leprae antibodies reacted with the fusion protein, the pattern of reactivity in the antibody responses was also similar for the various clinical types. The coding regions of clones LSR1 and LSR2 are identical. They show no homology with sequences stored in data banks and encode a protein of 89 amino acids with a calculated molecular mass of approximately 10 kDa.

Amino Acid Sequence↗
PubMed2026

A cost-effective conventional endpoint PCR assay for HLA-B*13:01 genotyping to guide personalized dapsone therapy in leprosy in low-resource settings.

BACKGROUND: Dapsone is a drug used to treat leprosy. Dapsone causes a highly morbid and potentially fatal severe drug hypersensitivity reaction (DHS) in 1-3% of leprosy cases. The allele HLA-B*13:01 is a known genetic risk factor for DHS. However, resource-intensive genotyping methods preclude its testing in resource-limited settings. This study aimed to develop an endpoint PCR assay to detect the presence of HLA-B*13:01. RESEARCH DESIGN AND METHODS: DNA was extracted from blood samples of leprosy patients at Anandaban Hospital, Nepal (2022-24). A duplex endpoint PCR was optimized and validated against a previously validated commercial qPCR method and NGS (next&#x2011;generation sequencing). RESULTS: In 113 samples, duplex PCR showed 100% (95% CI: 79.4-100%) sensitivity and 100% specificity (95% CI: 96.2-100%) compared to the validated qPCR method. The same accuracy was confirmed in 58 NGS-typed samples (concordance 98.3%, 95% CI: 90.7-99.9%). The assay reliably differentiated HLA-B*13:01 from closely related allele. Analytical sensitivity reached a lower detection limit of 100 genome equivalents (0.67 ng DNA/reaction). CONCLUSION: The developed duplex endpoint PCR offers a simple and affordable method for detecting HLA-B*13:01, suitable in low-resource settings. Its use may significantly reduce the risk of DHS by guiding safer drug choices prior to MDT initiation.

Humans↗
PubMed1999

Differential representations of memory T cell subsets are characteristic of polarized immunity in leprosy and atopic diseases.

We identified functionally polarized subsets of CD4 memory T cells on the basis of the expression of CD11a, CD45RA and CD62L. Within the several phenotypically distinct subsets of CD4 memory cells are two that, upon stimulation, produce primarily IL-4 (MT(2), CD45RA(-)CD62L(+)CD11a(dim)) or primarily IFN-gamma (MT(1), CD45RA(-)CD62L(-)CD11a(bright)). In addition, four other phenotypically distinct subsets of CD4 cells have unique cytokine profiles. To determine the clinical relevance of the representation of these cell types, we analyzed blood from patients with the chronic diseases leprosy and atopy. These diseases are characterized as immunologically polarized, since T cell responses in affected individuals are often strongly biased towards T(h)1 (dominated by IFN-gamma production) or T(h)2 (IL-4 production). We show here that this polarization reflects homeostatic or differentiation mechanisms affecting the representation of the functionally distinct subsets of memory CD4 T cells, MT(1) and MT(2). Significantly, the representation of the MT(1) and MT(2) subsets differs dramatically between subjects with tuberculoid leprosy (a T(h)1 disease), or lepromatous leprosy or atopic disease (T(h)2 diseases). However, there was no difference in the cytokine profiles of these or any of the other finely resolved CD4 subsets, when compared between individuals across all disease states. Thus, it is the representation of these subsets in peripheral blood that is diagnostic of the polarized state of the immune system.

CD4-Positive T-Lymphocytes↗