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1.
PLoS One ; 16(5): e0251631, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33984058

RESUMEN

The number of new cases of leprosy reported worldwide has remained essentially unchanged for the last decade despite continued global use of free multidrug therapy (MDT) provided to any diagnosed leprosy patient. In order to more effectively interrupt the chain of transmission, new strategies will be required to detect those with latent disease who contribute to furthering transmission. To improve the ability to diagnose leprosy earlier in asymptomatic infected individuals, we examined the combined use of two well-known biomarkers of M. leprae infection, namely the presence of M. leprae DNA by PCR from earlobe slit skin smears (SSS) and positive antibody titers to the M. leprae-specific antigen, Phenolic Glycolipid I (anti-PGL-I) from leprosy patients and household contacts living in seven hyperendemic cities in the northern state of Pará, Brazilian Amazon. Combining both tests increased sensitivity, specificity and accuracy over either test alone. A total of 466 individuals were evaluated, including 87 newly diagnosed leprosy patients, 52 post-treated patients, 296 household contacts and 31 healthy endemic controls. The highest frequency of double positives (PGL-I+/RLEP+) were detected in the new case group (40/87, 46%) with lower numbers for treated (12/52, 23.1%), household contacts (46/296, 15.5%) and healthy endemic controls (0/31, 0%). The frequencies in these groups were reversed for double negatives (PGL-I-/RLEP-) for new cases (6/87, 6.9%), treated leprosy cases (15/52, 28.8%) and the highest in household contacts (108/296, 36.5%) and healthy endemic controls (24/31, 77.4%). The data strongly suggest that household contacts that are double positive have latent disease, are likely contributing to shedding and transmission of disease to their close contacts and are at the highest risk of progressing to clinical disease. Proposed strategies to reduce leprosy transmission in highly endemic areas may include chemoprophylactic treatment of this group of individuals to stop the spread of bacilli to eventually lower new case detection rates in these areas.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Antígenos Bacterianos/inmunología , Glucolípidos/inmunología , Infección Latente/diagnóstico , Lepra/diagnóstico , Mycobacterium leprae/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , ADN Bacteriano/análisis , Femenino , Humanos , Infección Latente/inmunología , Lepra/inmunología , Masculino , Persona de Mediana Edad , Mycobacterium leprae/inmunología , Adulto Joven
2.
PLoS Negl Trop Dis ; 14(3): e0008127, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32203502

RESUMEN

Understanding the prevalence of M. leprae infection in armadillos is important because of evidence from Brazil and other countries of an association between contact with armadillos and the development of Hansen's Disease (leprosy). Our aim was to characterize studies which have investigated natural M. leprae infection in wild armadillos in Brazil, and to quantify and explore variability in the reported prevalence of infection. We conducted a systematic review (PROSPERO CRD42019155277) of publications in MEDLINE, EMBASE, Global Health, Scopus, LILACS, Biblioteca Digital Brasileira de Teses e Dissertações, Catálogo de Teses e Dissertações de CAPES, and Biblioteca Virtual em Saúde up to 10/2019 using Mesh and text search terms (in English, Portuguese, Spanish, and French). The 10 included studies represented a total sample of 302 armadillos comprising 207 (69%) Dasypus novemcinctus, 67 (22%) Euphractus sexcinctus, 16 (5%) Priodontes maximus, 10 (3%) Cabassous unicinctus, and 2 (1%) Cabassous tatouay from 7 different states. Methods used included histopathology (4 studies), PGL-1 and LID-1 antigen detection (4 studies) and examination for clinical signs of disease (4 studies). Eight studies used PCR of which 7 targeted the RLEP repetitive element and 3 tested for inhibitory substances. M. leprae prevalence by PCR ranged from 0% (in 3 studies) to 100% in one study, with a summary estimate of 9.4% (95% CI 0.4% to 73.1%) and a predictive interval of 0-100%. The average prevalence is equivalent to 1 in 10 armadillos in Brazil being infected with M. leprae, but wide variation in sample estimates means that the prevalence in any similar study would be entirely unpredictable. We propose instead that future studies aim to investigate transmission and persistence of M. leprae within and between armadillo populations, meanwhile adopting the precautionary principle to protect human health and an endangered species in Brazil.


Asunto(s)
Armadillos/microbiología , Lepra/epidemiología , Lepra/veterinaria , Mycobacterium leprae/aislamiento & purificación , Animales , Animales Salvajes/microbiología , Brasil/epidemiología , ADN Bacteriano/análisis , Bases de Datos Factuales , Mapeo Geográfico , Mycobacterium leprae/genética , Reacción en Cadena de la Polimerasa , Prevalencia , Secuencias Repetitivas de Ácidos Nucleicos , Zoonosis/epidemiología , Zoonosis/microbiología
3.
Sci Rep ; 9(1): 16675, 2019 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-31723144

RESUMEN

Household contacts (HHC) of leprosy patients exhibit high-risk of developing leprosy and contact tracing is helpful for early diagnosis. From 2011 to 2018,2,437 HHC were examined in a clinic in Rio de Janeiro, Brazil and 16S qPCR was used for diagnosis and monitoring of contacts. Fifty-four HHCs were clinically diagnosed with leprosy at intake. Another 25 exhibited leprosy-like skin lesions at intake, 8 of which were confirmed as having leprosy (50% of which were qPCR positive) and 17 of which were diagnosed with other skin diseases (6% qPCR positive). In skin biopsies, qPCR presented a sensitivity of 0.50 and specificity of 0.94. Furthermore, 955 healthy HHCs were followed-up for at least 3 years and skin scrapings were collected from earlobes for qPCR detection. Positive qPCR indicated a non-significant relative risk of 2.52 of developing the disease. During follow-up, those who progressed towards leprosy exhibited 20% qPCR positivity, compared to 9% of those who remained healthy. Disease-free survival rates indicated that age had a significant impact on disease progression, where patients over 60 had a greater chance of developing leprosy [HR = 32.4 (3.6-290.3)]. Contact tracing combined with qPCR may assist in early diagnosis and age is a risk factor for leprosy progression.


Asunto(s)
Trazado de Contacto/métodos , ADN Bacteriano/análisis , ADN Ribosómico/análisis , Composición Familiar , Lepra/diagnóstico , Mycobacterium leprae/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Adolescente , Adulto , Brasil/epidemiología , Estudios de Casos y Controles , Niño , Preescolar , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Lactante , Lepra/epidemiología , Lepra/genética , Masculino , Persona de Mediana Edad , Técnicas de Diagnóstico Molecular , Mycobacterium leprae/genética , Factores de Tiempo , Adulto Joven
4.
Homo ; 70(2): 105-118, 2019 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-31486822

RESUMEN

Orosháza site no. 10 (Southeast Hungary) contains the partially excavated archaeological remains of an 11-13th century CE Muslim merchant village and its cemetery located in close proximity to Christian villages of the same era. The skeleton of a young woman (grave no. 16) from the last phase of the cemetery use was identified with rhinomaxillary lesions associated with lepromatous leprosy. The right parietal bone also exhibited signs of cranial trauma, possibly caused by symbolic trepanation, a well-known ritual practice in the 9-11th century CE Carpathian Basin. The retrospective diagnosis of the disease was supported by ancient DNA analysis, as the samples were positive for Mycobacterium leprae aDNA, shown to be of genotype 3. Contrary to the general practice of the era, the body of the young female with severe signs of leprosy was interred among the regular graves of the Muslim cemetery in Orosháza, which may reflect the unique cultural background of the community.


Asunto(s)
Cementerios/historia , Islamismo/historia , Lepra/historia , Adulto , Huesos/microbiología , Huesos/patología , ADN Antiguo/análisis , ADN Bacteriano/análisis , ADN Bacteriano/genética , Femenino , Historia Medieval , Humanos , Hungría , Lepra/microbiología , Masculino , Mycobacterium leprae/genética , Paleopatología , Adulto Joven
5.
Am J Trop Med Hyg ; 100(4): 921-931, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30761984

RESUMEN

Neurotropism and infiltration by Mycobacterium leprae of peripheral nerves causing neuropathy are well established, but reports of central nervous system (CNS) damage are exceptional. We report CNS magnetic resonance imaging (MRI) abnormalities of the brain and spinal cord as well as lesions in nerve roots and plexus in leprosy patients. Eight patients aged between 17 and 41 years underwent detailed clinical, histopathological, and MRI evaluation. All had prominent sensory-motor deficits with hypopigmented and hypo/anesthetic skin patches and thickened peripheral nerves. All demonstrated M. Leprae DNA in affected peripheral nerve tissue. All received multidrug therapy (MDT). Two patients had brainstem lesions with enhancing facial nuclei and nerves, and one patient had a lesion in the nucleus ambiguus. Two patients had enhancing spinal cord lesions. Follow-up MRI performed in four cases showed resolution of brainstem and cord lesions after starting on MDT. Thickened brachial and lumbosacral plexus nerves were observed in six and two patients, respectively, which partially resolved on follow-up MRI in the two cases who had reimaging. The site and side of the MRI lesions corresponded with the location and side of neurological deficits. This precise clinico-radiological correlation of proximal lesions could be explained by an immune reaction in the gray matter corresponding to the involved peripheral nerves, retrograde axonal and gray matter changes, or infection of the CNS and plexus by lepra bacilli. Further study of the CNS in patients with leprous neuropathy is needed to establish the exact nature of these CNS MRI findings.


Asunto(s)
Encéfalo/diagnóstico por imagen , Lepra/complicaciones , Lepra/diagnóstico por imagen , Enfermedades de la Médula Espinal/diagnóstico por imagen , Médula Espinal/patología , Adolescente , Adulto , Encéfalo/microbiología , Encéfalo/patología , ADN Bacteriano/análisis , Quimioterapia Combinada , Femenino , Humanos , Leprostáticos/uso terapéutico , Lepra/tratamiento farmacológico , Lepra/patología , Imagen por Resonancia Magnética , Masculino , Mycobacterium leprae , Médula Espinal/diagnóstico por imagen , Médula Espinal/microbiología , Enfermedades de la Médula Espinal/microbiología , Adulto Joven
6.
Infect Genet Evol ; 72: 199-204, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30658215

RESUMEN

BACKGROUND: Mycobacterium leprae being an obligate intracellular parasite cannot be cultured in any artificial culture media but it has been shown to reside in wild armadillos in North America. Many studies suggested that M. leprae could be found in the environment and may have a role in continuing transmission of the disease. The exact role of the environment in the transmission dynamics is still speculative. The present study was undertaken to find out the presence of viable M. leprae around patients' environment like soil and water and association of free living pathogenic protozoa, Acanthamoeba which might play an important role in transmission of the disease. METHODS: Seven hundred soil and 400 water samples were collected from the surroundings of the houses of leprosy patients from endemic villages. Two hundred soil and 80 water samples were also collected from the surroundings of normal inhabitants from non-endemic villages as controls. These samples were screened for the presence of M. leprae and Acanthamoeba using DNA PCR. RNA was extracted from the PCR positive samples and Reverse Transcriptase - PCR targeting 16S rRNA gene region was performed for detection of viable M. leprae. RESULTS: We observed high PCR positivity in soil samples (218 out of 700; 31%) and water samples (73 out of 400; 18%). These samples when further screened for viability, it was observed that 106 soil samples (15% of total) and 34 water samples (8% of total) showed presence of 16S rRNA. We observed 18.3% of soil and 20.5% of water samples were PCR positive for Acanthamoeba. Soil samples from the control area, where no active leprosy case resided in the last 5 years, showed PCR positivity in 4 samples (2%) for M. leprae DNA in only soil samples with all water samples being negative. RT-PCR for all PCR positive soil samples was negative. Of the 106 soil samples positive for M. leprae RT-PCR, 30 samples were also positive for Acanthamoeba whereas out of 112 M. leprae RT-PCR negative but PCR positive samples only 10 samples were Acanthamoeba positive showing association of viability with presence of Acanthamoeba (p = .0021). Similarly, for water samples also, association of M. leprae viability with presence of Acanthamoeba was seen (p = .0009). CONCLUSION: This study suggests that the surrounding environment (soil and water) of leprosy patients contain viable M. leprae and the viability has association with Acanthamoeba which may provide a protective niche for M. leprae. This could play an important role in the focal transmission of the disease.


Asunto(s)
Acanthamoeba/microbiología , Lepra/transmisión , Mycobacterium leprae , Acanthamoeba/genética , Estudios Transversales , ADN Bacteriano/análisis , Humanos , India/epidemiología , Viabilidad Microbiana , Mycobacterium leprae/genética , ARN Bacteriano/análisis , ARN Ribosómico 16S/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Microbiología del Suelo , Microbiología del Agua
9.
J Clin Pathol ; 71(2): 148-153, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28735303

RESUMEN

AIMS: Acid-fast bacterium (AFB) identification from formalin-fixed paraffin-embedded (FFPE) tissues is challenging and may not be readily available to the clinical laboratory. A method to detect and identify AFB from FFPE tissues using PCR and pyrosequencing (PCR-Seq) was developed and evaluated. METHODS: The method was validated using spiked cell-clotted paraffin blocks before use with patients' specimens. DNA was extracted from tissue sections, and a 16S rRNA gene fragment was amplified and a signature sequence was produced on a PyroMark ID system. Sequences were aligned to established databases for AFB identification. Additional tissue sections were stained and examined for AFB. RESULTS: Both sensitivity and specificity were 100% on spiked cell-clotted blocks without cross-reactivity with non-AFB. Of 302 FFPE tissues from patients, 116 (38%) were AFB-stain positive; 83 (72%) of these had AFB identified. The 21 AFB identified included Mycobacterium tuberculosis complex (14 cases), Mycobacterium leprae (3), Mycobacterium genavense (2), Mycobacterium marinum-ulcerans group (3) and 17 other AFB (61). Thirteen cases were AFB-stain indeterminate and 4 were positive by the PCR-Seq method. Of the AFB stain-negative cases, 167 were negative and 6 were positive by PCR-Seq. CONCLUSIONS: The PCR-Seq method provided specific identification of various AFB species or complexes from FFPE tissues.


Asunto(s)
ADN Bacteriano/análisis , Mycobacterium/aislamiento & purificación , Nocardia/aislamiento & purificación , Adhesión en Parafina , Reacción en Cadena de la Polimerasa/métodos , Análisis de Secuencia de ADN/métodos , Fijación del Tejido , Formaldehído , Marcadores Genéticos , Humanos , Mycobacterium/genética , Nocardia/genética , ARN Ribosómico 16S/genética , Sensibilidad y Especificidad
10.
Microb Pathog ; 104: 336-339, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28137508

RESUMEN

Leprosy is a chronic infectious disease caused by Mycobacterium leprae. Identification of Mycobacterium leprae is difficult in part due to the inability of the leprosy bacillus to grow in vitro. A number of diagnostic methods for leprosy diagnosis have been proposed. Both serological tests and molecular probes have shown certain potential for detection and identification of Mycobacterium leprae in patients. In this study, we have investigated whether Mycobacterium leprae DNA from the nasal secretion of healthy household contacts and the non contacts could be detected through PCR amplification as a method to study the sub clinical infection in a community. A total of 200 samples, 100 each from contacts and non contacts representing all age groups and sex were included in this study. The M. leprae specific primer (proline-rich region) of pra gene was selected and PCR was performed using extracted DNA from the sample. A total of 13 samples were found to be positive for nasal PCR for pra gene among the male and female contacts out of which 7% were males and 6% were females. Even though several diagnostic tools are available to detect the cases of leprosy, they lack the specificity and sensitivity. PCR technology has demonstrated the improved diagnostic accuracy for epidemiological studies and requires minimal time. Although nasal PCR studies have been reported from many countries it is not usually recommended due to the high percentage of negative results in the contact.


Asunto(s)
Infecciones Asintomáticas/epidemiología , Secreciones Corporales/microbiología , Lepra/diagnóstico , Lepra/epidemiología , Mycobacterium leprae/aislamiento & purificación , Nariz/microbiología , Reacción en Cadena de la Polimerasa/métodos , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , ADN Bacteriano/análisis , ADN Bacteriano/genética , Femenino , Humanos , Lactante , Lepra/microbiología , Masculino , Persona de Mediana Edad , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium leprae/genética , Sensibilidad y Especificidad , Factores de Tiempo , Adulto Joven
11.
Microbiol Immunol ; 60(12): 817-823, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27925336

RESUMEN

In this study, attempts were made to culture this bacterium in media supplemented with a variety of biological materials to determine why cultivation of Mycobacterium leprae in vitro has not this far been successful. A slight increase in the number of cells in medium supplemented with human blood plasma and an extract of nude mouse tissue as observed after more than 3 months of cultivation at 30 °C. To ascertain whether this increase was real growth, the growth was analyzed by droplet digital PCR, which showed a slow increase in the copy number of cell-associated DNA and the release of a large amount of DNA into the culture medium from bacterial cells during cultivation. These results were supported by electron microscopic examination of M. leprae in infected mouse tissues, which showed that most of the replicated bacteria had degenerated and only a few cells survived. Based on these results, it was postulated that many of the replicated cells degenerate during M. leprae growth and that only a few cells remain to participate in the next growth stage. This means that, unlike other cultivable bacteria, the growth of M. leprae is not exponential and the number of cells therefore increase extremely slowly. Thus, accurate judging of the success of M. leprae cultivation requires observation of growth over a long period of time and careful measurement of the increase in number of viable cells.


Asunto(s)
Técnicas Bacteriológicas/métodos , Medios de Cultivo/química , Mycobacterium leprae/crecimiento & desarrollo , Animales , Sangre/metabolismo , ADN Bacteriano/análisis , Humanos , Ratones Desnudos , Viabilidad Microbiana , Microscopía Electrónica , Mycobacterium leprae/fisiología , Mycobacterium leprae/ultraestructura , Temperatura , Extractos de Tejidos/metabolismo
12.
Infect Genet Evol ; 45: 285-289, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27642139

RESUMEN

OBJECTIVE: The Objective of this study was to identify the strain diversity of Mycobacterium leprae in terms of SNP types and subtypes stratified as per genomic single nucleotide polymorphisms, in clinical isolates of leprosy patients from a tertiary care leprosy center in South India. Further, the associations of SNP types with clinical outcomes in leprosy were also investigated. METHODS: DNA was extracted from excisional skin biopsies of a total of 172 newly diagnosed untreated leprosy patients from a clinic in Tamil Nadu, in south India, that also serves patients from neighboring states. All the leprosy patients were those who voluntarily reported at the clinic during the study period of one year i.e., 2015. Clinical and histopathological details were collected at diagnosis and leprosy was confirmed through bacteriological smear examination and PCR for M. leprae specific RLEP region. SNP types and subtypes were determined by PCR amplification and Sanger sequencing of PCR products. RESULTS: M. leprae specific RLEP gene amplification was achieved in 160 out of 172 patients. Among 160 specimens 118(73.75%) were type 1 and 42 (26.25%) were type 2 and on subtyping it was noted that 88/160 (55.00%) were 1D, 25/160 (15.62%) 1C, 5/160 (3.12%) 1A, 33/160 (20.62%) 2G and 9/160 (5.62%) were 2H. CONCLUSION: Our results indicated that subtype 1D is predominant in the south Indian population. We also noted 2G, 1C and 1A in the patient sample tested. Additionally we identified subtype 2H for the first time in India.


Asunto(s)
Genoma Bacteriano/genética , Lepra/microbiología , Mycobacterium leprae/genética , Polimorfismo de Nucleótido Simple/genética , Adolescente , Adulto , Niño , ADN Bacteriano/análisis , ADN Bacteriano/genética , Femenino , Humanos , India/epidemiología , Lepra/epidemiología , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Filogeografía , Adulto Joven
13.
Artículo en Inglés | MEDLINE | ID: mdl-26728806

RESUMEN

BACKGROUND: Leprosy, a chronic disease caused by Mycobacterium leprae, is a public health concern in certain countries, including India. Although the prevalence of the disease has fallen drastically over time, new cases continue to occur at nearly the same rate in many regions. Several endemic pockets have been observed in India and elsewhere. The precise dynamics of leprosy transmission are still not clearly understood. Both live bacilli as well as M. leprae DNA have been detected in the soil and water of endemic areas; they possibly play an important role in disease transmission. AIMS: To study the occurrence of viable M. leprae in environmental samples collected from areas of residence of patients with active leprosy. METHODS: The study was conducted on 169 newly diagnosed leprosy patients in Ghatampur, Uttar Pradesh, India. Soil and water samples were collected from their areas of residence using a standardized protocol. An equal number of soil and water samples were also collected from non-patient areas of the same or adjoining villages. The environmental samples collected from the patients surroundings were subjected to 16S ribosomal RNA gene analysis after obtaining informed consent. RESULTS: About a quarter of the environmental samples collected from patient areas, (25.4% of soil samples and 24.2% of water samples) were found to be positive for specific 16S ribosomal RNA genes of M. leprae. Environmental samples collected from non-patient areas were all found negative for M. leprae 16S ribosomal RNA genes. LIMITATIONS: The major limitation of the study was that the sample size was small. CONCLUSION: The study demonstrated the presence of viable strains of M. leprae in skin smear samples of paucibacillary patients and multibacillary patients, as well as in the environmental samples obtained from around their houses. This could play an important role in the continued transmission of leprosy.


Asunto(s)
Lepra/epidemiología , Viabilidad Microbiana , Mycobacterium leprae/aislamiento & purificación , Microbiología del Suelo , Contaminación del Agua , Adulto , Estudios de Cohortes , ADN Bacteriano/análisis , Progresión de la Enfermedad , Enfermedades Endémicas/estadística & datos numéricos , Monitoreo del Ambiente/métodos , Femenino , Humanos , Incidencia , India/epidemiología , Lepra/diagnóstico , Lepra/microbiología , Masculino , Persona de Mediana Edad , Mycobacterium leprae/genética , Salud Pública , ARN Ribosómico 16S/análisis , Medición de Riesgo , Rol , Muestreo
14.
Tuberculosis (Edinb) ; 95 Suppl 1: S140-4, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25773651

RESUMEN

Many tuberculosis and leprosy infections are latent or paucibacillary, suggesting a long time-scale for host and pathogen co-existence. Palaeopathology enables recognition of archaeological cases and PCR detects pathogen ancient DNA (aDNA). Mycobacterium tuberculosis and Mycobacterium leprae cell wall lipids are more stable than aDNA and restrict permeability, thereby possibly aiding long-term persistence of pathogen aDNA. Amplification of aDNA, using specific PCR primers designed for short fragments and linked to fluorescent probes, gives good results, especially when designed to target multi-copy loci. Such studies have confirmed tuberculosis and leprosy, including co-infections. Many tuberculosis cases have non-specific or no visible skeletal pathology, consistent with the natural history of this disease. M. tuberculosis and M. leprae are obligate parasites, closely associated with their human host following recent clonal distribution. Therefore genotyping based on single nucleotide polymorphisms (SNPs) can indicate their origins, spread and phylogeny. Knowledge of extant genetic lineages at particular times in past human populations can be obtained from well-preserved specimens where molecular typing is possible, using deletion analysis, microsatellite analysis and whole genome sequencing. Such studies have identified non-bovine tuberculosis from a Pleistocene bison from 17,500 years BP, human tuberculosis from 9000 years ago and leprosy from over 2000 years ago.


Asunto(s)
ADN Bacteriano/análisis , Evolución Molecular , Lepra/genética , Mycobacterium leprae/genética , Mycobacterium tuberculosis/genética , Tuberculosis/genética , Técnicas de Tipificación Bacteriana , Coinfección/complicaciones , Coinfección/genética , Coinfección/historia , ADN Bacteriano/genética , Genoma Bacteriano , Historia Antigua , Humanos , Lepra/complicaciones , Lepra/historia , Tipificación Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico , Paleopatología/métodos , Reacción en Cadena de la Polimerasa , Tuberculosis/complicaciones , Tuberculosis/historia
15.
Mem Inst Oswaldo Cruz ; 109(7): 944-7, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25411000

RESUMEN

The diagnosis of single-lesion paucibacillary leprosy remains a challenge. Reviews by expert dermatopathologists and quantitative polymerase chain reaction (qPCR) results obtained from 66 single-plaque biopsy samples were compared. Histological findings were graded as high (HP), medium (MP) or low (LP) probability of leprosy or other dermatopathy (OD). Mycobacterium leprae-specific genes were detected using qPCR. The biopsies of 47 out of 57 clinically diagnosed patients who received multidrug therapy were classified as HP/MP, eight of which were qPCR negative. In the LP/OD (n = 19), two out of eight untreated patients showed positive qPCR results. In the absence of typical histopathological features, qPCR may be utilised to aid in final patient diagnosis, thus reducing overtreatment and delay in diagnosis.


Asunto(s)
ADN Bacteriano/análisis , Lepra Paucibacilar/diagnóstico , Mycobacterium leprae/genética , Piel/patología , Biopsia/clasificación , Técnicas de Apoyo para la Decisión , Femenino , Humanos , Lepra Paucibacilar/clasificación , Masculino , Reacción en Cadena de la Polimerasa/métodos , Piel/lesiones , Centros de Atención Terciaria
16.
Mem. Inst. Oswaldo Cruz ; 109(7): 944-947, 11/2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-728804

RESUMEN

The diagnosis of single-lesion paucibacillary leprosy remains a challenge. Reviews by expert dermatopathologists and quantitative polymerase chain reaction (qPCR) results obtained from 66 single-plaque biopsy samples were compared. Histological findings were graded as high (HP), medium (MP) or low (LP) probability of leprosy or other dermatopathy (OD). Mycobacterium leprae-specific genes were detected using qPCR. The biopsies of 47 out of 57 clinically diagnosed patients who received multidrug therapy were classified as HP/MP, eight of which were qPCR negative. In the LP/OD (n = 19), two out of eight untreated patients showed positive qPCR results. In the absence of typical histopathological features, qPCR may be utilised to aid in final patient diagnosis, thus reducing overtreatment and delay in diagnosis.


Asunto(s)
Femenino , Humanos , Masculino , ADN Bacteriano/análisis , Lepra Paucibacilar/diagnóstico , Mycobacterium leprae/genética , Piel/patología , Biopsia/clasificación , Técnicas de Apoyo para la Decisión , Lepra Paucibacilar/clasificación , Reacción en Cadena de la Polimerasa/métodos , Piel/lesiones , Centros de Atención Terciaria
17.
Am J Trop Med Hyg ; 90(3): 524-9, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24493677

RESUMEN

The TaqMan real-time polymerase chain reaction (PCR) assay was evaluated systematically with respect to the standard curve, linear range, and used for detecting Mycobacterium leprae DNA in paraffin-embedded skin biopsy specimens from 60 confirmed leprosy patients and three healthy individuals and 29 other dermatoses and bacterial DNA from 21 different species. The test was further evaluated with 51 paucibacillary (PB) patients. The results showed that the test had good sensitivity (8 fg) and good specificity with no cross-reactivity with 21 other bacterial species and the control specimens, except one with Xanthomatosis. The real-time PCR detection rate for the 51 PB specimens was 74.5% (38 of 51). We conclude that the real-time PCR test is a useful adjunct test for diagnosing early stage or PB leprosy cases.


Asunto(s)
Lepra Paucibacilar/diagnóstico , Mycobacterium leprae/genética , Piel/microbiología , Adolescente , Adulto , Anciano , Carga Bacteriana , Biopsia , Estudios de Casos y Controles , Niño , ADN Bacteriano/análisis , Femenino , Humanos , Secuencias Repetitivas Esparcidas/genética , Lepra Paucibacilar/microbiología , Masculino , Persona de Mediana Edad , Adhesión en Parafina , Reacción en Cadena en Tiempo Real de la Polimerasa , Sensibilidad y Especificidad , Enfermedades de la Piel/diagnóstico , Enfermedades de la Piel/microbiología , Adulto Joven
18.
Appl Immunohistochem Mol Morphol ; 22(3): 222-30, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23702646

RESUMEN

The diagnosis of pure neural leprosy (PNL) is based on clinical and laboratory data, including the histopathology of nerve biopsy specimens and detection of Mycobacterium leprae DNA by polymerase chain reaction (PCR). Given that histopathologic examination and PCR methods may not be sufficient to confirm the diagnosis, immunolabeling of lipoarabinomanan (LAM) and/or phenolic glycolipid 1 (PGL-1) M. leprae wall components was utilized in the present investigation in an attempt to detect any vestigial presence of M. leprae in acid-fast bacilli (AFB) nerve samples. Twenty-three PNL nerve samples (6 AFB and 17 AFBPCR) were cryosectioned and subjected to LAM and PGL-1 immunohistochemical staining by immunoperoxidase. Five nonleprosy nerve samples were used as controls. The 6 AFB samples showed LAM/PGL-1 immunoreactivity. Among the 17 AFB samples, 8 revealed LAM and/or PGL-1 immunoreactivity. In 17 AFBPCR patients, just 7 yielded LAM and/or PGL-1 nerve results. In the PNL cases, the detection of immunolabeled LAM and PGL-1 in the nerve samples would have contributed to an enhanced diagnostic efficiency in the absence of molecular diagnostic facilities.


Asunto(s)
Antígenos Bacterianos/metabolismo , ADN Bacteriano/análisis , Glucolípidos/metabolismo , Lepra Tuberculoide/diagnóstico , Lipopolisacáridos/metabolismo , Mycobacterium leprae/genética , Nervios Periféricos/metabolismo , Adolescente , Adulto , Anciano , Biopsia , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Nervios Periféricos/inmunología , Mejoramiento de la Calidad , Adulto Joven
19.
PLoS Negl Trop Dis ; 7(8): e2404, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24179562

RESUMEN

BACKGROUND: The inability of Mycobacterium leprae to grow on axenic media has necessitated specialized techniques in order to determine viability of this organism. The purpose of this study was to develop a simple and sensitive molecular assay for determining M. leprae viability directly from infected tissues. METHODOLOGY/PRINCIPLE FINDINGS: Two M. leprae-specific quantitative reverse transcription PCR (qRT-PCR) assays based on the expression levels of esxA, encoding the ESAT-6 protein, and hsp18, encoding the heat shock 18 kDa protein, were developed and tested using infected footpad (FP) tissues of both immunocompetent and immunocompromised (athymic nu/nu) mice. In addition, the ability of these assays to detect the effects of anti-leprosy drug treatment on M. leprae viability was determined using rifampin and rifapentine, each at 10 mg/kg for 1, 5, or 20 daily doses, in the athymic nu/nu FP model. Molecular enumeration (RLEP PCR) and viability determinations (qRT-PCR) were performed via Taqman methodology on DNA and RNA, respectively, purified from ethanol-fixed FP tissue and compared with conventional enumeration (microscopic counting of acid fast bacilli) and viability assays (radiorespirometry, viability staining) which utilized bacilli freshly harvested from the contralateral FP. Both molecular and conventional assays demonstrated growth and high viability of M. leprae in nu/nu FPs over a 4 month infection period. In contrast, viability was markedly decreased by 8 weeks in immunocompetent mice. Rifapentine significantly reduced bacterial viability after 5 treatments, whereas rifampin required up to 20 treatments for the same efficacy. Neither drug was effective after a single treatment. In addition, host gene expression was monitored with the same RNA preparations. CONCLUSIONS: hsp18 and esxA qRT-PCR are sensitive molecular indicators, reliably detecting viability of M. leprae in tissues without the need for bacterial isolation or immediate processing, making these assays applicable for in vivo drug screening and promising for clinical and field applications.


Asunto(s)
Técnicas Bacteriológicas/métodos , Lepra/microbiología , Mycobacterium leprae/citología , Reacción en Cadena de la Polimerasa/métodos , Animales , Antígenos Bacterianos/análisis , Antígenos Bacterianos/genética , Antígenos Bacterianos/metabolismo , Proteínas Bacterianas/análisis , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Citocinas/análisis , Citocinas/genética , Citocinas/metabolismo , ADN Bacteriano/análisis , ADN Bacteriano/aislamiento & purificación , Modelos Animales de Enfermedad , Proteínas de Choque Térmico/análisis , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Leprostáticos/farmacología , Lepra/tratamiento farmacológico , Ratones , Ratones Desnudos , Viabilidad Microbiana/efectos de los fármacos , Mycobacterium leprae/efectos de los fármacos , Mycobacterium leprae/aislamiento & purificación
20.
Indian J Dermatol Venereol Leprol ; 79(5): 693-700, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23974586

RESUMEN

BACKGROUND: Leprosy is not always an easy disease to diagnose, and patients can remain undiagnosed for longtime, not only at the peripheral clinics but also even at places with higher medical facilities, so, there is an urgent need for rapid and definitive modalities for leprosy diagnosis. This prospective study evaluates the ability of Fite-Faraco staining (FF staining) and multiplex polymerase chain reaction (PCR) over hematoxylin and eosin staining (H and E staining) and Ziehl-Neelsen staining (ZN staining). AIMS: The aim of this perspective study is to evaluate the effectiveness of FF staining in combination with multiplex PCR for the early and rapid diagnosis of leprosy than any other coexisting diagnosis tool. METHODS: Patients with new skin patches or nodules with or without evidence of nerve damage were selected for the study. Punch biopsy was collected according to standard procedures. Each biopsy sample was divided into two equal parts, one half was fixed in 4% (v/v) buffered neutral formalin and then accordingly embedded in paraffin. Sections were stained by three different methods: H and E staining for histopathological examination, ZN staining, and FF staining for detection of acid-fast bacilli (AFB). And the other part was subjected for DNA extraction and PCR was carried out by the obtained DNA sample. RESULTS: H and E staining, ZN staining, FF staining, and PCR yield 58.2%, 50.9%, 60%, and 67.7% successful diagnosis of leprosy. The true diagnostic performances for these techniques were as follows: H and E staining - sensitivity 70.6%, positive predictive value (PPV) 81.9%, negative predictive value (NPV) 53.6%. For ZN staining - sensitivity 59.9%, PPV 69%, NPV 45.7%. For FF staining - sensitivity 74.6%, PPV 85.9%, NPV 56.7%, and for PCR - sensitivity 87.8%, PPV 95.6%, NPV 71.2%. CONCLUSION: The combination of FF staining and PCR was shown to provide a rapid and definitive diagnosis in the majority of leprosy suspected cases with a higher positive likelihood ratio (+LR) of 7.76 and 2.716, respectively, than H and E staining of 2.244 and ZN staining of 1.378.


Asunto(s)
Lepra/diagnóstico , Lepra/genética , Reacción en Cadena de la Polimerasa Multiplex/métodos , Mycobacterium leprae/genética , Mycobacterium leprae/aislamiento & purificación , Coloración y Etiquetado/métodos , Biopsia , ADN Bacteriano/análisis , ADN Bacteriano/genética , Eosina Amarillenta-(YS) , Hematoxilina , Humanos , Lepra/patología , Técnicas Microbiológicas , Estudios Prospectivos
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