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Revista Gaucha de Enfermagem Jun 2018To analyze the concept of patient discharge in leprosy. (Review)
Review
OBJECTIVE
To analyze the concept of patient discharge in leprosy.
METHODS
Theoretical study guided in the methodological framework of concept analysis. A bibliographical survey was held from December 2015 to January 2016 using the following bases: SCOPUS, CINAHL, PubMed, LILACS, SCIELO and BDENF, by use of the descriptors "Leprosy" and "Patient Discharge", resulting in 13 studies.
RESULTS
The following were identified as possible uses for the concept: discharge by cure, drug use discharge, bacteriological discharge and post-discharge. The attributes defined were completion of multidrug therapy, completion of multidrug therapy for paucibacillary leprosy, completion of multidrug therapy for multibacillary leprosy and cure from leprosy. The presence of an M. leprae infection, symptoms present in skin and peripheral nerves, diagnosis and treatment and leprosy reactions were identified as antecedents. Consequents were exclusion from the active leprosy record and continuity of health care. One case model and one opposing case were presented.
CONCLUSIONS
The analysis broadened the concept "discharge in leprosy", providing other meanings than the clinical definition of multidrug therapy.
Topics: Bibliometrics; Drug Therapy, Combination; Humans; Leprostatic Agents; Leprosy; Models, Biological; Mycobacterium leprae; Patient Discharge
PubMed: 29933418
DOI: 10.1590/1983-1447.2017.04.63290 -
Clinical Infectious Diseases : An... May 2020Leprosy has been treated with multidrug therapy, which has been distributed for free across the globe and regarded as highly efficient. However, the impossibility of...
BACKGROUND
Leprosy has been treated with multidrug therapy, which has been distributed for free across the globe and regarded as highly efficient. However, the impossibility of growing Mycobacterium leprae in axenic media has historically impaired assessments of M. leprae resistance, a parameter only recently detectable through molecular methods.
METHODS
A systematic, population-based search for M. leprae resistance in suspected leprosy relapse cases and contacts was performed in Prata Village, an isolated, hyperendemic, former leprosy colony located in the Brazilian Amazon. Results led to an extended active search involving the entire Prata population. Confirmed leprosy cases were investigated for bacterial resistance using a combination of in vivo testing and direct sequencing of resistance genes folP1, rpoB, and gyrA. A molecular epidemiology analysis was performed using data from 17 variable number tandem repeats (VNTR).
RESULTS
Mycobacterium leprae was obtained from biopsies of 37 leprosy cases (18 relapses and 19 new cases): 16 (43.24%) displayed drug-resistance variants. Multidrug resistance to rifampicin and dapsone was observed in 8 relapses and 4 new cases. Single resistance to rifampicin was detected in 1 new case. Resistance to dapsone was present in 2 relapses and 1 new case. Combined molecular resistance and VNTR data revealed evidence of intra-familial primary transmission of resistant M. leprae.
CONCLUSIONS
A comprehensive, population-based systematic approach to investigate M. leprae resistance in a unique population revealed an alarming scenario of the emergence and transmission of resistant strains. These findings may be used for the development of new strategies for surveillance of drug resistance in other populations.
Topics: Brazil; Drug Resistance, Bacterial; Drug Therapy, Combination; Humans; Leprostatic Agents; Leprosy; Microbial Sensitivity Tests; Mycobacterium leprae; Pharmaceutical Preparations
PubMed: 31260522
DOI: 10.1093/cid/ciz570 -
PLoS Neglected Tropical Diseases Jan 2018Leprosy is caused by the bacterial pathogens Mycobacterium leprae and Mycobacterium lepromatosis. Apart from humans, animals such as nine-banded armadillos in the...
Leprosy is caused by the bacterial pathogens Mycobacterium leprae and Mycobacterium lepromatosis. Apart from humans, animals such as nine-banded armadillos in the Americas and red squirrels in the British Isles are naturally infected with M. leprae. Natural leprosy has also been reported in certain nonhuman primates, but it is not known whether these occurrences are due to incidental infections by human M. leprae strains or by M. leprae strains specific to nonhuman primates. In this study, complete M. leprae genomes from three naturally infected nonhuman primates (a chimpanzee from Sierra Leone, a sooty mangabey from West Africa, and a cynomolgus macaque from The Philippines) were sequenced. Phylogenetic analyses showed that the cynomolgus macaque M. leprae strain is most closely related to a human M. leprae strain from New Caledonia, whereas the chimpanzee and sooty mangabey M. leprae strains belong to a human M. leprae lineage commonly found in West Africa. Additionally, samples from ring-tailed lemurs from the Bezà Mahafaly Special Reserve, Madagascar, and chimpanzees from Ngogo, Kibale National Park, Uganda, were screened using quantitative PCR assays, to assess the prevalence of M. leprae in wild nonhuman primates. However, these samples did not show evidence of M. leprae infection. Overall, this study adds genomic data for nonhuman primate M. leprae strains to the existing M. leprae literature and finds that this pathogen can be transmitted from humans to nonhuman primates as well as between nonhuman primate species. While the prevalence of natural leprosy in nonhuman primates is likely low, nevertheless, future studies should continue to explore the prevalence of leprosy-causing pathogens in the wild.
Topics: Africa, Western; Animals; Cercocebus atys; Genetic Variation; Genome, Bacterial; Lemur; Leprosy; Macaca fascicularis; Mycobacterium leprae; Pan troglodytes; Philippines; Phylogeny; Primate Diseases
PubMed: 29381722
DOI: 10.1371/journal.pntd.0006190 -
Emerging Infectious Diseases Mar 2023We examined armadillos from museum collections in the United States using molecular assays to detect leprosy-causing bacilli. We found Mycobacterium leprae bacilli in...
We examined armadillos from museum collections in the United States using molecular assays to detect leprosy-causing bacilli. We found Mycobacterium leprae bacilli in samples from the United States, Bolivia, and Paraguay; prevalence was 14.8% in nine-banded armadillos. US isolates belonged to subtype 3I-2, suggesting long-term circulation of this genotype.
Topics: Humans; United States; Animals; Mycobacterium leprae; Armadillos; Leprosy; Museums; Genotype
PubMed: 36823763
DOI: 10.3201/eid2903.221636 -
Journal of Clinical Microbiology Aug 2019Many pathogens that caused devastating disease throughout human history, such as , , and , remain problematic today. Historical bacterial genomes represent a unique... (Review)
Review
Many pathogens that caused devastating disease throughout human history, such as , , and , remain problematic today. Historical bacterial genomes represent a unique source of genetic information and advancements in sequencing technologies have allowed unprecedented insights from this previously understudied resource. This minireview brings together example studies which have utilized ancient DNA, individual historical isolates (both extant and dead) and collections of historical isolates. The studies span human history and highlight the contribution that sequencing and analysis of historical bacterial genomes have made to a wide variety of fields. From providing retrospective diagnosis, to uncovering epidemiological pathways and characterizing genetic diversity, there is clear evidence for the utility of historical isolate studies in understanding disease today. Studies utilizing historical isolate collections, such as those from the National Collection of Type Cultures, the American Type Culture Collection, and the Institut Pasteur, offer enhanced insight since they typically span a wide time period encompassing important historical events and are useful for the investigating the phylodynamics of pathogens. Furthermore, historical sequencing studies are particularly useful for looking into the evolution of antimicrobial resistance, a major public health concern. In summary, although there are limitations to working with historical bacterial isolates, especially when utilizing ancient DNA, continued improvement in molecular and sequencing technologies and the resourcefulness of investigators mean this area of study will continue to expand and contribute to the understanding of pathogens.
Topics: Anti-Bacterial Agents; Bacteria; DNA, Ancient; Drug Resistance, Multiple, Bacterial; Evolution, Molecular; Genetic Variation; Genome, Bacterial; Humans; Mycobacterium leprae; Mycobacterium tuberculosis; Phylogeny; Sequence Analysis, DNA; Yersinia pestis
PubMed: 31092597
DOI: 10.1128/JCM.00100-19 -
Microbiology Spectrum Jun 2016The key question our work has sought to address has been, "What are the necessary and sufficient conditions that engender protection from intracellular pathogens in the... (Review)
Review
The key question our work has sought to address has been, "What are the necessary and sufficient conditions that engender protection from intracellular pathogens in the human host?" The origins of this work derive from a long-standing interest in the mechanisms of protection against two such paradigmatic intracellular pathogens, Mycobacterium tuberculosis and Mycobacterium leprae, that have brilliantly adapted to the human host. It was obvious that these pathogens, which cause chronic diseases and persist in macrophages, must have acquired subtle strategies to resist host microbicidal mechanisms, yet since the vast majority of individuals infected with M. tuberculosis do not develop disease, there must be some potent human antimicrobial mechanisms. What follows is not a comprehensive review of the vast literature on the role of human macrophages in protection against infectious disease, but a summary of the research in our two laboratories with collaborators that we hope has contributed to some understanding of mechanisms of resistance and pathogenesis. While mouse models revealed some necessary conditions for protection, e.g., innate immunity, Th1 cells and their cytokines, and major histocompatibility complex class I-restricted T cells, here we emphasize multiple antimicrobial mechanisms that exist in human macrophages that differ from those of most experimental animals. Prominent here is the vitamin D-dependent antimicrobial pathway common to human macrophages activated by innate and acquired immune responses, mediated by antimicrobial peptides, e.g., cathelicidin, through an interleukin-15- and interleukin-32-dependent common pathway that is necessary for macrophage killing of M. tuberculosis in vitro.
Topics: Animals; Disease Resistance; Host-Pathogen Interactions; Humans; Macrophages; Mycobacterium leprae; Mycobacterium tuberculosis
PubMed: 27337485
DOI: 10.1128/microbiolspec.MCHD-0006-2015 -
Philosophical Transactions of the Royal... Nov 2020As one of the oldest known human diseases, leprosy or Hansen's disease remains a public health concern around the world with over 200 000 new cases in 2018. Most human...
As one of the oldest known human diseases, leprosy or Hansen's disease remains a public health concern around the world with over 200 000 new cases in 2018. Most human leprosy cases are caused by , but a small number of cases are now known to be caused by , a sister taxon of . The global pattern of genomic variation in is not well defined. Particularly, in the Pacific Islands, the origins of leprosy are disputed. Historically, it has been argued that leprosy arrived on the islands during nineteenth century colonialism, but some oral traditions and palaeopathological evidence suggest an older introduction. To address this, as well as investigate patterns of pathogen exchange across the Pacific Islands, we extracted DNA from 39 formalin-fixed paraffin-embedded biopsy blocks dating to 1992-2016. Using whole-genome enrichment and next-generation sequencing, we produced nine genomes dating to 1998-2015 and ranging from 4-63× depth of coverage. Phylogenetic analyses indicate that these strains belong to basal lineages within the phylogeny, specifically falling in branches 0 and 5. The phylogeographical patterning and evolutionary dating analysis of these strains support a pre-modern introduction of into the Pacific Islands. This article is part of the theme issue 'Insights into health and disease from ancient biomolecules'.
Topics: Adolescent; Adult; Aged; American Samoa; Biological Evolution; Child; Evolution, Molecular; Female; Genome, Bacterial; Hawaii; Humans; Leprosy; Male; Micronesia; Middle Aged; Mycobacterium leprae; Pacific Islands; Phylogeography; Young Adult
PubMed: 33012236
DOI: 10.1098/rstb.2019.0582 -
Current Protocols Feb 2022Mycobacterium leprae, the etiologic agent of leprosy, cannot be cultured on artificial media. This characteristic, coupled with its long generation time, presents a...
Mycobacterium leprae, the etiologic agent of leprosy, cannot be cultured on artificial media. This characteristic, coupled with its long generation time, presents a number of unique challenges to studying this pathogen. One of the difficulties facing both researchers and clinicians is the absence of a rapid test to measure the viability of M. leprae in clinical or experimental specimens. The lack of such a tool limits the understanding of M. leprae immunopathogenesis and makes determining the efficacy of drug treatments difficult. With this in mind, we developed a robust two-step molecular viability assay (MVA) that first enumerates the M. leprae in the tissue; then, this data is used to normalize bacterial RNA quantities for the second step, in which the expression of M. leprae esxA and hsp18 are measured. This assay is specific and sensitive enough to be used on most clinical samples. This protocol describes the steps required to extract DNA and RNA from M. leprae-infected tissue, enumerate M. leprae, and measure M. leprae viability based on the normalized expression of two M. leprae-specific genes (hsp18 and esxA). This protocol also outlines an optimal laboratory design and workflow for performing this assay. © 2022 The Leprosy Mission Nepal. Current Protocols published by Wiley Periodicals LLC. This article has been contributed to by US Government employees and their work is in the public domain in the USA. Basic Protocol 1: DNA and RNA P purification from M. leprae-infected tissue Basic Protocol 2: Enumeration of M. leprae by RLEP qPCR on the DNA fraction Basic Protocol 3: Calculation of M. leprae per tissue and normalization of RNA Basic Protocol 4: Reverse-transcription of normalized RNA to generate cDNA Basic Protocol 5: Determination of M. leprae viability using HSP18 and ESXA qPCR on the cDNA Support Protocol 1: M. leprae qPCR primer/probe stock preparation Support Protocol 2: Preparation of plasmid stocks and standard curves.
Topics: DNA, Bacterial; Humans; Leprosy; Mycobacterium leprae; RNA, Bacterial; Real-Time Polymerase Chain Reaction
PubMed: 35113486
DOI: 10.1002/cpz1.359 -
BMC Infectious Diseases Nov 2021Nucleic acid-based amplification tests (NAAT), above all (q)PCR, have been applied for the detection of Mycobacterium leprae in leprosy cases and household contacts with...
Nucleic acid-based amplification tests (NAAT), above all (q)PCR, have been applied for the detection of Mycobacterium leprae in leprosy cases and household contacts with subclinical infection. However, their application in the field poses a range of technical challenges. Loop-mediated isothermal amplification (LAMP), as a promising point-of-care NAAT does not require sophisticated laboratory equipment, is easy to perform, and is applicable for decentralized diagnosis at the primary health care level. Among a range of gene targets, the M. leprae specific repetitive element RLEP is regarded as highly sensitive and specific for diagnostic applications. METHODS: Our group developed and validated a dry-reagent-based (DRB) RLEP LAMP, provided product specifications for customization of a ready-to-use kit (intended for commercial production) and compared it against the in-house prototype. The assays were optimized for application on a Genie III portable fluorometer. For technical validation, 40 "must not detect RLEP" samples derived from RLEP qPCR negative exposed and non-exposed individuals, as well as from patients with other conditions and a set of closely related mycobacterial cultures, were tested together with 25 "must detect RLEP" samples derived from qPCR confirmed leprosy patients. For clinical validation, 150 RLEP qPCR tested samples were analyzed, consisting of the following categories: high-positive samples of multibacillary (MB) leprosy patients (> 10.000 bacilli/extract), medium-positive samples of MB leprosy patients (1.001-10.000 bacilli/extract), low-positive samples of MB leprosy patients (1-1.000 bacilli/extract), endemic controls and healthy non-exposed controls; each n = 30. RESULTS: Technical validation: both LAMP formats had a limit of detection of 1.000 RLEP copies, i.e. 43-27 bacilli, a sensitivity of 92% (in-house protocol)/100% (ready-to-use protocol) and a specificity of 100%. Reagents were stable for at least 1 year at 22 °C. Clinical validation: Both formats showed a negativity rate of 100% and a positivity rate of 100% for high-positive samples and 93-100% for medium positive samples, together with a positive predictive value of 100% and semi-quantitative results. The positivity rate for low-positive samples was 77% (in-house protocol)/43% (ready-to-use protocol) and differed significantly between both formats. CONCLUSIONS: The ready-to-use RLEP DRB LAMP assay constitutes an ASSURED test ready for field-based evaluation trials aiming for routine diagnosis of leprosy at the primary health care level.
Topics: DNA, Bacterial; Humans; Laboratories; Leprosy; Molecular Diagnostic Techniques; Mycobacterium leprae; Nucleic Acid Amplification Techniques; Point-of-Care Testing; Real-Time Polymerase Chain Reaction; Sensitivity and Specificity
PubMed: 34823479
DOI: 10.1186/s12879-021-06882-2 -
PLoS Neglected Tropical Diseases Feb 2022Leprosy is a chronic dermato-neurological disease caused by Mycobacterium leprae, an obligate intracellular bacterium. Timely detection is a challenge in leprosy...
Leprosy is a chronic dermato-neurological disease caused by Mycobacterium leprae, an obligate intracellular bacterium. Timely detection is a challenge in leprosy diagnosis, relying on clinical examination and trained health professionals. Furthermore, adequate care and transmission control depend on early and reliable pathogen detection. Here, we describe a qPCR test for routine diagnosis of leprosy-suspected patients. The reaction simultaneously amplifies two specific Mycobacterium leprae targets (16S rRNA and RLEP), and the human 18S rRNA gene as internal control. The limit of detection was estimated to be 2.29 copies of the M. leprae genome. Analytical specificity was evaluated using a panel of 20 other skin pathogenic microorganisms and Mycobacteria, showing no cross-reactivity. Intra- and inter-operator Cp variation was evaluated using dilution curves of M. leprae DNA or a synthetic gene, and no significant difference was observed between three operators in two different laboratories. The multiplex assay was evaluated using 97 patient samples with clinical and histopathological leprosy confirmation, displaying high diagnostic sensitivity (91%) and specificity (100%). Validation tests in an independent panel of 50 samples confirmed sensitivity and specificity of 97% and 98%, respectively. Importantly, assay performance remained stable for at least five months. Our results show that the newly developed multiplex qPCR effectively and specifically detects M. leprae DNA in skin samples, contributing to an efficient diagnosis that expedites the appropriate treatment.
Topics: Adolescent; Adult; Aged; Child; Child, Preschool; DNA, Bacterial; Female; Humans; Indicators and Reagents; Infant; Leprosy; Male; Middle Aged; Molecular Diagnostic Techniques; Multiplex Polymerase Chain Reaction; Mycobacterium leprae; Real-Time Polymerase Chain Reaction; Sensitivity and Specificity; Young Adult
PubMed: 35180224
DOI: 10.1371/journal.pntd.0009850