Mycobacterium lepromatosis Lepromatous Leprosy in US Citizen Who Traveled to Disease-Endemic Areas.
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SUBMITTER: Virk A
PROVIDER: S-EPMC5652441 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:A 43-year-old woman of Mayan origin from Quintana Roo, Mexico, was diagnosed with diffuse lepromatous leprosy. The etiologic bacillus was determined to be Mycobacterium lepromatosis instead of Mycobacterium leprae. This case likely represents the first report of this leprosy form and its agent in the southeastern tip of Mexico.
| S-EPMC4609715 | biostudies-literature
Project description:Mycobacterium lepromatosis is a newly discovered leprosy-causing organism. Preliminary phylogenetic analysis of its 16S rRNA gene and a few other gene segments revealed significant divergence from Mycobacterium leprae, a well-known cause of leprosy, that justifies the status of M. lepromatosis as a new species. In this study we analyzed the sequences of 20 genes and pseudogenes (22,814 nucleotides). Overall, the level of matching of these sequences with M. leprae sequences was 90.9%, which substantiated the species-level difference; the levels of matching for the 16S rRNA genes and 14 protein-encoding genes were 98.0% and 93.1%, respectively, but the level of matching for five pseudogenes was only 79.1%. Five conserved protein-encoding genes were selected to construct phylogenetic trees and to calculate the numbers of synonymous substitutions (dS values) and nonsynonymous substitutions (dN values) in the two species. Robust phylogenetic trees constructed using concatenated alignment of these genes placed M. lepromatosis and M. leprae in a tight cluster with long terminal branches, implying that the divergence occurred long ago. The dS and dN values were also much higher than those for other closest pairs of mycobacteria. The dS values were 14 to 28% of the dS values for M. leprae and Mycobacterium tuberculosis, a more divergent pair of species. These results thus indicate that M. lepromatosis and M. leprae diverged approximately 10 million years ago. The M. lepromatosis pseudogenes analyzed that were also pseudogenes in M. leprae showed nearly neutral evolution, and their relative ages were similar to those of M. leprae pseudogenes, suggesting that they were pseudogenes before divergence. Taken together, the results described above indicate that M. lepromatosis and M. leprae diverged from a common ancestor after the massive gene inactivation event described previously for M. leprae.
| S-EPMC2747882 | biostudies-literature
Project description:[This retracts the article on p. 1677 in vol. 11, PMID: 30349325.].
| S-EPMC6306048 | biostudies-literature
Project description:IntroductionThe most commonly noted reactions in leprosy patients are type 1 reactions and erythema nodosum leprosum, with some rare phenomenon of host response known as Lucio phenomenon or leprosy of Lucio and Latapi which is caused by Mycobacterium lepromatosis. So far, no case of M. lepromatosis has been reported from India.Materials and methodsThe main objective of this study was to detect any positive cases of M. lepromatosis in India with such a complication. We screened slit skin smear/biopsy samples from lepromatous leprosy (LL) patients reporting to The Leprosy Mission Community Hospitals across the country. Eighty-eight slit skin smears were collected from leprosy patients in 70% ethanol. DNA was extracted from all these samples. Polymerase chain reaction (PCR) was done for 2 genes; one set was for 16S rRNA and the other set was for coproporphyrinogen III oxidase (hemN) gene. Then, sequencing was done for all positive amplicons. Homology of the sequences was analyzed using the Basic Local Alignment Search Tool at the National Center of Biotechnology Information database.ResultsAmong 88 isolates, we found 4 positive cases for M. lepromatosis. All 4 were LL cases with a bacteriological index ranging from 2+ to 4+. On the basis of the National Center of Biotechnology Information Basic Local Alignment Search Tool analysis, the sequenced amplicons of both genes matched with the M. lepromatosis 16S rRNA and phosphofructokinase genes but not with hemN gene of lepromatosis. This is the first report for the presence of M. lepromatosis in LL cases from India.ConclusionThis new species M. lepromatosis exists beyond Mexico, Singapore and it is the cause of DLL in India also. It may cause dual infections along with M. leprae in endemic areas like India.
| S-EPMC6188107 | biostudies-literature
Project description:Leprosy is caused by Mycobacterium leprae and Mycobacterium lepromatosis. We report construction and analyses of the complete genome sequence of M. lepromatosis FJ924. The genome contained 3,271,694 nucleotides to encode 1,789 functional genes and 1,564 pseudogenes. It shared 1,420 genes and 885 pseudogenes (71.4%) with M. leprae but differed in 1,281 genes and pseudogenes (28.6%). In phylogeny, the leprosy bacilli started from a most recent common ancestor (MRCA) that diverged ~30 million years ago (Mya) from environmental organism Mycobacterium haemophilum. The MRCA then underwent reductive evolution with pseudogenization, gene loss, and chromosomal rearrangements. Analysis of the shared pseudogenes estimated the pseudogenization event ~14 Mya, shortly before species bifurcation. Afterwards, genomic changes occurred to lesser extent in each species. Like M. leprae, four major types of highly repetitive sequences were detected in M. lepromatosis, contributing to chromosomal rearrangements within and after MRCA. Variations in genes and copy numbers were noted, such as three copies of the gene encoding bifunctional diguanylate cyclase/phosphodiesterase in M. lepromatosis, but single copy in M. leprae; 6 genes encoding the TetR family transcriptional regulators in M. lepromatosis, but 11 such genes in M. leprae; presence of hemW gene in M. lepromatosis, but absence in M. leprae; and others. These variations likely aid unique pathogenesis, such as diffuse lepromatous leprosy associated with M. lepromatosis, while the shared genomic features should explain the common pathogenesis of dermatitis and neuritis in leprosy. Together, these findings and the genomic data of M. lepromatosis may facilitate future research and care for leprosy. IMPORTANCE Leprosy is a dreaded infection that still affects millions of people worldwide. Mycobacterium lepromatosis is a recently recognized cause in addition to the well-known Mycobacterium leprae. M. lepromatosis is likely specific for diffuse lepromatous leprosy, a severe form of the infection and endemic in Mexico. This study constructed and annotated the complete genome sequence of M. lepromatosis FJ924 and performed comparative genomic analyses with related mycobacteria. The results afford new and refined insights into the genome size, gene repertoire, pseudogenes, phylogenomic relationship, genome organization and plasticity, process and timing of reductive evolution, and genetic and proteomic basis for pathogenesis. The availability of the complete M. lepromatosis genome may prove to be useful for future research and care for the infection.
| S-EPMC9248898 | biostudies-literature
Project description:Regulatory T (Treg) cells are known for their role in maintaining self-tolerance and balancing immune reactions in autoimmune diseases and chronic infections. However, regulatory mechanisms can also lead to prolonged survival of pathogens in chronic infections like leprosy and tuberculosis (TB). Despite high humoral responses against Mycobacterium leprae (M. leprae), lepromatous leprosy (LL) patients have the characteristic inability to generate T helper 1 (Th1) responses against the bacterium. In this study, we investigated the unresponsiveness to M. leprae in peripheral blood mononuclear cells (PBMC) of LL patients by analysis of IFN-? responses to M. leprae before and after depletion of CD25+ cells, by cell subsets analysis of PBMC and by immunohistochemistry of patients' skin lesions. Depletion of CD25+ cells from total PBMC identified two groups of LL patients: 7/18 (38.8%) gained in vitro responsiveness towards M. leprae after depletion of CD25+ cells, which was reversed to M. leprae-specific T-cell unresponsiveness by addition of autologous CD25+ cells. In contrast, 11/18 (61.1%) remained anergic in the absence of CD25+ T-cells. For both groups mitogen-induced IFN-? was, however, not affected by depletion of CD25+ cells. In M. leprae responding healthy controls, treated lepromatous leprosy (LL) and borderline tuberculoid leprosy (BT) patients, depletion of CD25+ cells only slightly increased the IFN-? response. Furthermore, cell subset analysis showed significantly higher (p?=?0.02) numbers of FoxP3+ CD8+CD25+ T-cells in LL compared to BT patients, whereas confocal microscopy of skin biopsies revealed increased numbers of CD68+CD163+ as well as FoxP3+ cells in lesions of LL compared to tuberculoid and borderline tuberculoid leprosy (TT/BT) lesions. Thus, these data show that CD25+ Treg cells play a role in M. leprae-Th1 unresponsiveness in LL.
| S-EPMC3983090 | biostudies-literature
Project description:Mycobacterium lepromatosis is an uncultured human pathogen associated with diffuse lepromatous leprosy and a reactional state known as Lucio's phenomenon. By using deep sequencing with and without DNA enrichment, we obtained the near-complete genome sequence of M. lepromatosis present in a skin biopsy from a Mexican patient, and compared it with that of Mycobacterium leprae, which has undergone extensive reductive evolution. The genomes display extensive synteny and are similar in size (∼3.27 Mb). Protein-coding genes share 93% nucleotide sequence identity, whereas pseudogenes are only 82% identical. The events that led to pseudogenization of 50% of the genome likely occurred before divergence from their most recent common ancestor (MRCA), and both M. lepromatosis and M. leprae have since accumulated new pseudogenes or acquired specific deletions. Functional comparisons suggest that M. lepromatosis has lost several enzymes required for amino acid synthesis whereas M. leprae has a defective heme pathway. M. lepromatosis has retained all functions required to infect the Schwann cells of the peripheral nervous system and therefore may also be neuropathogenic. A phylogeographic survey of 227 leprosy biopsies by differential PCR revealed that 221 contained M. leprae whereas only six, all from Mexico, harbored M. lepromatosis. Phylogenetic comparisons indicate that M. lepromatosis is closer than M. leprae to the MRCA, and a Bayesian dating analysis suggests that they diverged from their MRCA approximately 13.9 Mya. Thus, despite their ancient separation, the two leprosy bacilli are remarkably conserved and still cause similar pathologic conditions.
| S-EPMC4394283 | biostudies-literature
Project description:In 2008, bacilli from 2 Hansen disease (leprosy) cases were identified as a new species, Mycobacterium lepromatosis. We conducted a systematic review of studies investigating M. lepromatosis as a cause of HD. Twenty-one case reports described 27 patients with PCR-confirmed M. lepromatosis infection (6 dual M. leprae/M. lepromatosis): 10 case-patients in the United States (7 originally from Mexico), 6 in Mexico, 3 in the Dominican Republic, 2 each in Singapore and Myanmar, and 1 each in Indonesia, Paraguay, Cuba, and Canada. Twelve specimen surveys reported 1,098 PCR-positive findings from 1,428 specimens, including M. lepromatosis in 44.9% (133/296) from Mexico, 3.8% (5/133) in Colombia, 12.5% (10/80) in Brazil, and 0.9% (2/224) from the Asia-Pacific region. Biases toward investigating M. lepromatosis as an agent in cases of diffuse lepromatous leprosy or from Mesoamerica precluded conclusions about clinicopathologic manifestations and geographic distribution. Current multidrug treatments seem effective for this infection.
| S-EPMC10310392 | biostudies-literature
Project description:During recent years, comparative genomic analysis has allowed the identification of Mycobacterium leprae-specific genes with potential application for the diagnosis of leprosy. In a previous study, 58 synthetic peptides derived from these sequences were tested for their ability to induce production of IFN-? in PBMC from endemic controls (EC) with unknown exposure to M. leprae, household contacts of leprosy patients and patients, indicating the potential of these synthetic peptides for the diagnosis of sub- or preclinical forms of leprosy. In the present study, the patterns of IFN-? release of the individuals exposed or non-exposed to M. leprae were compared using an Artificial Neural Network algorithm, and the most promising M. leprae peptides for the identification of exposed people were selected. This subset of M. leprae-specific peptides allowed the differentiation of groups of individuals from sites hyperendemic for leprosy versus those from areas with lower level detection rates. A progressive reduction in the IFN-? levels in response to the peptides was seen when contacts of multibacillary (MB) patients were compared to other less exposed groups, suggesting a down modulation of IFN-? production with an increase in bacillary load or exposure to M. leprae. The data generated indicate that an IFN-? assay based on these peptides applied individually or as a pool can be used as a new tool for predicting the magnitude of M. leprae transmission in a given population.
| S-EPMC3335884 | biostudies-literature
Project description:Neuritis is a frequent complication of Myocobacteria leprae infection and treatment due to the variety of mechanisms through which it can occur. Not only can mycobacterial invasion into peripheral nerves directly cause damage and inflammation, but immune-mediated inflammatory episodes (termed leprosy reactions) can also manifest as neuritis at any point during infection. Treatment of leprosy reactions with thalidomide can also lead to neuritis due to an adverse drug effect. Neuritis can emerge years after initial diagnosis and treatment, although it is most frequently found at time of diagnosis or early into the treatment course. Treatment of neuritis is dependent on high-dose corticosteroid therapy as well as therapy for suspected underlying etiology. Here, we present a case of ulnar neuritis presenting in a patient with lepromatous leprosy four years after treatment of initial infection, with subsequent improvement after corticosteroid burst while maintained on thalidomide therapy.
| S-EPMC6715229 | biostudies-literature