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1.
Int J Infect Dis ; 88: 65-72, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499206

RESUMO

OBJECTIVE: To assess the effectiveness of single-dose rifampicin (SDR) after bacillus Calmette-Guérin (BCG) vaccination in preventing leprosy in contacts. METHODS: This was a single-centre, cluster-randomized controlled trial at a leprosy control programme in northwest Bangladesh. Participants were the 14988 contacts of 1552 new leprosy patients who were randomized into the SDR-arm (n=7379) and the SDR+arm (n=7609). In the intervention group, BCG vaccination was followed by SDR 8-12 weeks later. In the control group, BCG vaccination only was given. Follow-up was performed at 1year and 2 years after intake. The main outcome measure was the occurrence of leprosy. RESULTS: The incidence rate per 10000 person-years at risk was 44 in the SDR-arm and 31 in the SDR+arm at 1year; the incidence rate was 34 in the SDR-arm and 41 in the SDR+arm at 2 years. There was a statistically non-significant (p=0.148; 42%) reduction for paucibacillary (PB) leprosy in the SDR+ arm at 1 year. Of all new cases, 33.6% appeared within 8-12 weeks after BCG vaccination. CONCLUSIONS: In the first year, SDR after BCG vaccination reduced the incidence of PB leprosy among contacts by 42%. This was a statistically non-significant reduction due to the limited number of cases after SDR was administered. To what extent SDR suppresses excess leprosy cases after BCG vaccination is difficult to establish because many cases appeared before the SDR intervention. TRIAL REGISTRATION: Netherlands Trial Register: NTR3087.


Assuntos
Vacina BCG/administração & dosagem , Hansenostáticos/administração & dosagem , Hanseníase/prevenção & controle , Rifampina/administração & dosagem , Adolescente , Adulto , Bangladesh , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Hanseníase/diagnóstico , Hanseníase/tratamento farmacológico , Hanseníase/microbiologia , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/efeitos dos fármacos , Mycobacterium leprae/fisiologia , Vacinação , Adulto Jovem
2.
EBioMedicine ; 47: 301-308, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31422044

RESUMO

BACKGROUND: Transmission of Mycobacterium leprae, the pathogen causing leprosy, is still persistent. To facilitate timely (prophylactic) treatment and reduce transmission it is vital to both early diagnose leprosy, and identify infected individuals lacking clinical symptoms. However, leprosy-specific biomarkers are limited, particularly for paucibacillary disease. Therefore, our objective was to identify new biomarkers for leprosy and assess their applicability in point-of-care (POC) tests. METHODS: Using multiplex-bead-arrays, 60 host-proteins were measured in a cross-sectional approach in 24-h whole blood assays (WBAs) collected in Bangladesh (79 patients; 54 contacts; 51 endemic controls (EC)). Next, 17 promising biomarkers were validated in WBAs of a separate cohort (55 patients; 27 EC). Finally, in a third cohort (36 patients; 20 EC), five candidate markers detectable in plasma were assessed for application in POC tests. FINDINGS: This study identified three new biomarkers for leprosy (ApoA1, IL-1Ra, S100A12), and confirmed five previously described biomarkers (CCL4, CRP, IL-10, IP-10, αPGL-I IgM). Overnight stimulation in WBAs provided increased specificity for leprosy and was required for IL-10, IL-1Ra and CCL4. The remaining five biomarkers were directly detectable in plasma, hence suitable for rapid POC tests. Indeed, lateral flow assays (LFAs) utilizing this five-marker profile detected both multi- and paucibacillary leprosy patients with variable immune responses. INTERPRETATION: Application of novel host-biomarker profiles to rapid, quantitative LFAs improves leprosy diagnosis and allows POC testing in low-resource settings. This platform can thus aid diagnosis and classification of leprosy and also provides a tool to detect M.leprae infection in large-scale contact screening in the field.


Assuntos
Biomarcadores , Interações Hospedeiro-Patógeno , Hanseníase/sangue , Hanseníase/diagnóstico , Testes Imediatos , Adolescente , Adulto , Biomarcadores/sangue , Criança , Pré-Escolar , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Lactente , Recém-Nascido , Hanseníase/microbiologia , Hanseníase/transmissão , Masculino , Testes Imediatos/normas , Curva ROC , Sensibilidade e Especificidade , Fluxo de Trabalho , Adulto Jovem
3.
Front Immunol ; 9: 629, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29670618

RESUMO

Background: Notwithstanding its beneficial immunoprophylactic outcomes regarding leprosy and childhood TB, BCG vaccination may cause adverse events, particularly of the skin. However, this local hyper-immune reactivity cannot be predicted before vaccination, nor is its association with protection against leprosy known. In this study we investigated the occurrence of adverse events after BCG (re)vaccination in contacts of leprosy patients and analyzed whether the concomitant systemic anti-mycobacterial immunity was associated with these skin manifestations. Methods: Within a randomized controlled BCG vaccination trial in Bangladesh, 14,828 contacts of newly diagnosed leprosy patients received BCG vaccination between 2012 and 2017 and were examined for adverse events 8 to 12 weeks post-vaccination. From a selection of vaccinated contacts, venous blood was obtained at follow-up examination and stimulated with Mycobacterium leprae (M. leprae) antigens in overnight whole-blood assays (WBA). M. leprae phenolic glycolipid-I-specific antibodies and 32 cytokines were determined in WBAs of 13 individuals with and 13 individuals without adverse events after vaccination. Results: Out of the 14,828 contacts who received BCG vaccination, 50 (0.34%) presented with adverse events, mainly (80%) consisting of skin ulcers. Based on the presence of BCG scars, 30 of these contacts (60%) had received BCG in this study as a booster vaccination. Similar to the pathological T-cell immunity observed for tuberculoid leprosy patients, contacts with adverse events at the site of BCG vaccination showed elevated IFN-γ levels in response to M. leprae-specific proteins in WBA. However, decreased levels of sCD40L in serum and GRO (CXCL1) in response to M. leprae simultaneously indicated less T-cell regulation in these individuals, potentially causing uncontrolled T-cell immunity damaging the skin. Conclusion: Skin complications after BCG vaccination present surrogate markers for protective immunity against leprosy, but also indicate a higher risk of developing tuberculoid leprosy. Clinical Trial Registration: Netherlands Trial Register: NTR3087.


Assuntos
Hanseníase/imunologia , Mycobacterium bovis/imunologia , Mycobacterium leprae/fisiologia , Úlcera Cutânea/imunologia , Pele/imunologia , Linfócitos T/imunologia , Adolescente , Adulto , Anticorpos Antibacterianos/sangue , Bangladesh , Ligante de CD40/sangue , Quimiocina CXCL1/sangue , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Interferon gama/metabolismo , Hanseníase/complicações , Ativação Linfocitária , Masculino , Úlcera Cutânea/etiologia , Vacinação/efeitos adversos , Adulto Jovem
4.
PLoS Negl Trop Dis ; 11(12): e0006083, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29228004

RESUMO

BACKGROUND: Despite elimination efforts, the number of Mycobacterium leprae (M. leprae) infected individuals who develop leprosy, is still substantial. Solid evidence exists that individuals living in close proximity to patients are at increased risk to develop leprosy. Early diagnosis of leprosy in endemic areas requires field-friendly tests that identify individuals at risk of developing the disease before clinical manifestation. Such assays will simultaneously contribute to reduction of current diagnostic delay as well as transmission. Antibody (Ab) levels directed against the M.leprae-specific phenolic glycolipid I (PGL-I) represents a surrogate marker for bacterial load. However, it is insufficiently defined whether anti-PGL-I antibodies can be utilized as prognostic biomarkers for disease in contacts. Particularly, in Bangladesh, where paucibacillary (PB) patients form the majority of leprosy cases, anti-PGL-I serology is an inadequate method for leprosy screening in contacts as a directive for prophylactic treatment. METHODS: Between 2002 and 2009, fingerstick blood from leprosy patients' contacts without clinical signs of disease from a field-trial in Bangladesh was collected on filter paper at three time points covering six years of follow-up per person. Analysis of anti-PGL-I Ab levels for 25 contacts who developed leprosy during follow-up and 199 contacts who were not diagnosed with leprosy, was performed by ELISA after elution of bloodspots from filter paper. RESULTS: Anti-PGL-I Ab levels at intake did not significantly differ between contacts who developed leprosy during the study and those who remained free of disease. Moreover, anti-PGL-I serology was not prognostic in this population as no significant correlation was identified between anti-PGL-I Ab levels at intake and the onset of leprosy. CONCLUSION: In this highly endemic population in Bangladesh, no association was observed between anti-PGL-I Ab levels and onset of disease, urging the need for an extended, more specific biomarker signature for early detection of leprosy in this area. TRIAL REGISTRATION: ClinicalTrials.gov ISRCTN61223447.


Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Glicolipídeos/imunologia , Hanseníase/diagnóstico , Mycobacterium leprae/imunologia , Adolescente , Adulto , Bangladesh/epidemiologia , Biomarcadores/sangue , Criança , Pré-Escolar , Estudos de Coortes , Diagnóstico Tardio/prevenção & controle , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Lactente , Hanseníase/imunologia , Hanseníase/transmissão , Estudos Longitudinais , Masculino , Mycobacterium leprae/isolamento & purificação , Estudos Prospectivos , Adulto Jovem
5.
Sci Rep ; 6: 34260, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27682181

RESUMO

Leprosy is a debilitating, infectious disease caused by Mycobacterium leprae. Despite the availability of multidrug therapy, transmission is unremitting. Thus, early identification of M. leprae infection is essential to reduce transmission. The immune response to M. leprae is determined by host genetics, resulting in paucibacillary (PB) and multibacillary (MB) leprosy associated with dominant cellular or humoral immunity, respectively. This spectral pathology of leprosy compels detection of immunity to M. leprae to be based on multiple, diverse biomarkers. In this study we have applied quantitative user friendly lateral flow assays (LFAs) for four immune markers (anti-PGL-I antibodies, IL-10, CCL4 and IP-10) for whole blood samples from a longitudinal BCG vaccination field-trial in Bangladesh. Different biomarker profiles, in contrast to single markers, distinguished M. leprae infected from non-infected test groups, patients from household contacts (HHC) and endemic controls (EC), or MB from PB patients. The test protocol presented in this study merging detection of innate, adaptive cellular as well as humoral immunity, thus provides a convenient tool to measure specific biomarker profiles for M. leprae infection and leprosy utilizing a field-friendly technology.

6.
Vaccine ; 33(13): 1562-7, 2015 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-25701674

RESUMO

BACKGROUND: Although BCG is used as a vaccine against tuberculosis, it also protects against leprosy. Previous evaluation over 18 years of an intervention of two doses BCG for 3536 household contacts of leprosy patients showed that 28 (23%) out of 122 contacts diagnosed with leprosy, developed symptoms 2-10 months after vaccination. This study describes contacts of leprosy patients in Bangladesh who developed leprosy within 12 weeks after receiving a single BCG dose. METHODS: A cluster RCT in Bangladesh aims to study the effectiveness of the BCG vaccine versus BCG in combination with single dose rifampicin (SDR) given 2 to 3 months after BCG, in the prevention of leprosy among contacts of newly diagnosed leprosy patients. During the first 1,5 years of this ongoing trial we identified contacts who developed leprosy within the first 12 weeks after receiving BCG vaccination, the timeframe before SDR is given. RESULTS: We identified 21 contacts who developed leprosy within 12 weeks after BCG vaccination among 5196 vaccinated contacts (0.40%). All 21 cases presented with paucibacillary (PB) leprosy, including children and adults. About half of these cases had previously received BCG vaccination as indicated by the presence of a BCG scar; 43% presented with signs of nerve function impairment and/or Type 1 (reversal) reaction, and 56% of the index patients had multibacillary (MB) leprosy. CONCLUSION: An unexpectedly high proportion of healthy contacts of leprosy patients presented with PB leprosy within 12 weeks after receiving BCG vaccination, possibly as a result of boosted cell-mediated immunity by homologues of Mycobacterium leprae antigens in BCG. Various immunological mechanisms could underlie this phenomenon, including an immune reconstitution inflammatory syndrome (IRIS). Further studies are required to determine whether BCG vaccination merely altered the incubation period or actually changed the course of the infection from self-limiting, subclinical infection to manifest disease.


Assuntos
Antígenos de Bactérias/imunologia , Vacina BCG/efeitos adversos , Vacina BCG/imunologia , Hanseníase Paucibacilar/etiologia , Hanseníase Paucibacilar/prevenção & controle , Mycobacterium leprae/imunologia , Rifampina/administração & dosagem , Adolescente , Adulto , Idoso , Vacina BCG/uso terapêutico , Bangladesh , Criança , Quimioterapia Combinada , Características da Família , Feminino , Humanos , Síndrome Inflamatória da Reconstituição Imune/etiologia , Imunidade Celular , Hansenostáticos/administração & dosagem , Hanseníase Paucibacilar/imunologia , Masculino , Pessoa de Meia-Idade , Vacinação , Adulto Jovem
7.
BMC Infect Dis ; 13: 456, 2013 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-24088534

RESUMO

BACKGROUND: Despite almost 30 years of effective chemotherapy with MDT, the global new case detection rate of leprosy has remained quite constant over the past years. New tools and methodologies are necessary to interrupt the transmission of M. leprae. Single-dose rifampicin (SDR) has been shown to prevent 57% of incident cases of leprosy in the first two years, when given to contacts of newly diagnosed cases. Immunization of contacts with BCG has been less well documented, but appears to have a preventive effect lasting up to 9 years. However, one major disadvantage is the occurrence of excess cases within the first year after immunization. The objective of this study is to examine the effect of chemoprophylaxis with SDR and immunoprophylaxis with BCG on the clinical outcome as well as on host immune responses and gene expression profiles in contacts of newly diagnosed leprosy patients. We hypothesize that the effects of both interventions may be complementary, causing the combined preventive outcome to be significant and long-lasting. METHODS/DESIGN: Through a cluster randomized controlled trial we compare immunization with BCG alone with BCG plus SDR in contacts of new leprosy cases. Contact groups of around 15 persons will be established for each of the 1300 leprosy patients included in the trial, resulting in approximately 20,000 contacts in total. BCG will be administered to the intervention group followed by SDR, 2 months later. The control group will receive BCG only. In total 10,000 contacts will be included in both intervention arms over a 2-year period. Follow-up will take place one year as well as two years after intake. The primary outcome is the occurrence of clinical leprosy within two years. Simultaneously with vaccination and SDR, blood samples for in vitro analyses will be obtained from 300 contacts participating in the trial to determine the effect of these chemo- and immunoprophylactic interventions on immune and genetic host parameters. DISCUSSION: Combined chemoprophylaxis and immunoprophylaxis is potentially a very powerful and innovative tool aimed at contacts of leprosy patients that could reduce the transmission of M. leprae markedly. The trial intends to substantiate this potential preventive effect. Evaluation of immune and genetic biomarker profiles will allow identification of pathogenic versus (BCG-induced) protective host biomarkers and could lead to effective prophylactic interventions for leprosy using optimized tools for identification of individuals who are most at risk of developing disease. TRIAL REGISTRATION: Netherlands Trial Register: NTR3087.


Assuntos
Vacina BCG/administração & dosagem , Hanseníase/tratamento farmacológico , Rifampina/administração & dosagem , Vacina BCG/efeitos adversos , Vacina BCG/imunologia , Quimioprevenção , Quimioterapia Combinada , Humanos , Hanseníase/imunologia , Hanseníase/microbiologia , Hanseníase/prevenção & controle , Mycobacterium leprae/efeitos dos fármacos , Mycobacterium leprae/fisiologia , Países Baixos , Rifampina/efeitos adversos
8.
Case Rep Med ; 2011: 675807, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21541186

RESUMO

We report two immigrants with tuberculosis of the skull base and a review of the literature. A Somalian man presented with bilateral otitis media, hearing loss, and facial and abducens palsy. Imaging showed involvement of both mastoid and petrous bones, extending via the skull base to the nasopharynx, suggesting tuberculosis which was confirmed by characteristic histology and positive auramine staining, while Ziehl-Neelsen staining and PCR were negative. A Sudanese man presented with torticollis and deviation of the uvula due to paresis of N. IX and XI. Imaging showed a retropharyngeal abscess and lysis of the clivus. Histology, acid-fast staining, and PCR were negative. Both patients had a positive Quantiferon TB Gold in-tube result and improved rapidly after empiric treatment for tuberculosis. Cultures eventually yielded M. tuberculosis. These unusual cases exemplify the many faces of tuberculosis and the importance to include tuberculosis in the differential diagnosis of unexplained problems.

9.
Reprod Sci ; 14(8): 780-5, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18089596

RESUMO

Female patients with classical galactosemia (galactose-1-phosphate uridyltransferase [GALT] deficiency) frequently suffer from premature ovarian failure, despite treatment with a galactose-restricted diet. Earlier research has suggested an association between heterozygosity for GALT mutations and early menopause. This study evaluates the effect of carriership for classical galactosemia on ovarian reserve and menopausal age. Proven female carriers of classical galactosemia were recruited via the Dutch Galactosemia Society. All 58 participants underwent a structured interview regarding fertility, smoking status, and menopause. To determine ovarian reserve, 42 premenopausal GALT carriers underwent ovarian antral follicle count (AFC) by transvaginal ultrasound and early follicular phase blood sampling for hormonal measurement of follicle-stimulating hormone (FSH), inhibin B, and anti-Müllerian hormone (AMH). These ovarian reserve parameters were compared with a cohort of proven fertile women (n = 166). The mean age at menopause in GALT carriers was 49.7 years, which is not different from the mean age at menopause in the general population in the Netherlands. There was no difference in FSH, inhibin B, and AMH levels or in the AFC (when corrected for age and smoking status) between 42 premenopausal GALT carriers and controls. The authors conclude that there is no evidence that GALT mutation carriership affects ovarian reserve or menopausal age.


Assuntos
Galactosemias/genética , Menopausa/genética , Folículo Ovariano/fisiologia , Adulto , Hormônio Antimülleriano/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Galactosemias/sangue , Heterozigoto , Humanos , Inibinas/sangue , Menopausa/sangue , Pessoa de Meia-Idade
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