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EBioMedicine Jul 2023Expansion of antimicrobial resistance monitoring and epidemiological surveillance are key components of the WHO strategy towards zero leprosy. The inability to grow...
Hi-plex deep amplicon sequencing for identification, high-resolution genotyping and multidrug resistance prediction of Mycobacterium leprae directly from patient biopsies by using Deeplex Myc-Lep.
BACKGROUND
Expansion of antimicrobial resistance monitoring and epidemiological surveillance are key components of the WHO strategy towards zero leprosy. The inability to grow Mycobacterium leprae in vitro precludes routine phenotypic drug susceptibility testing, and only limited molecular tests are available. We evaluated a culture-free targeted deep sequencing assay, for mycobacterial identification, genotyping based on 18 canonical SNPs and 11 core variable-number tandem-repeat (VNTR) markers, and detection of rifampicin, dapsone and fluoroquinolone resistance-associated mutations in rpoB/ctpC/ctpI, folP1, gyrA/gyrB, respectively, and hypermutation-associated mutations in nth.
METHODS
The limit of detection (LOD) was determined using DNA of M. leprae reference strains and from 246 skin biopsies and 74 slit skin smears of leprosy patients, with genome copies quantified by RLEP qPCR. Sequencing results were evaluated versus whole genome sequencing (WGS) data of 14 strains, and versus VNTR-fragment length analysis (FLA) results of 89 clinical specimens.
FINDINGS
The LOD for sequencing success ranged between 80 and 3000 genome copies, depending on the sample type. The LOD for minority variants was 10%. All SNPs detected in targets by WGS were identified except in a clinical sample where WGS revealed two dapsone resistance-conferring mutations instead of one by Deeplex Myc-Lep, due to partial duplication of the sulfamide-binding domain in folP1. SNPs detected uniquely by Deeplex Myc-Lep were missed by WGS due to insufficient coverage. Concordance with VNTR-FLA results was 99.4% (926/932 alleles).
INTERPRETATION
Deeplex Myc-Lep may help improve the diagnosis and surveillance of leprosy. Gene domain duplication is an original putative drug resistance-related genetic adaptation in M. leprae.
FUNDING
EDCTP2 programme supported by the European Union (grant number RIA2017NIM-1847 -PEOPLE). EDCTP, R2Stop: Effect:Hope, The Mission To End Leprosy, the Flemish Fonds Wetenschappelijk Onderzoek.
Topics: Humans; Mycobacterium leprae; Microbial Sensitivity Tests; Genotype; Drug Resistance, Bacterial; Mycobacterium tuberculosis; Leprosy; Dapsone; Biopsy; Drug Resistance, Multiple
PubMed: 37327675
DOI: 10.1016/j.ebiom.2023.104649 -
The Journal of Investigative Dermatology May 2023Dapsone hypersensitivity syndrome (DHS) is restricted to HLA-B∗13:01. However, the positive predictive value for HLA-B∗13:01 is only 7.8%. To explore the potential...
Dapsone hypersensitivity syndrome (DHS) is restricted to HLA-B∗13:01. However, the positive predictive value for HLA-B∗13:01 is only 7.8%. To explore the potential coexisting factors involved in the occurrence of DHS, we carried out a GWAS and a genome-wide DNA methylation profile analysis comparing patients with DHS with dapsone-tolerant control subjects (all carrying HLA-B∗13:01). No non-HLA SNPs associated with DHS were identified at the genome-wide level. However, the pathway of antigen processing and presentation was enriched in patients with DHS, and the gene TAP2 was identified. Expression of TAP2 and its molecular chaperone, TAP1, were validated by quantitative PCR, and in vitro functional experiments were performed. The results showed that patients with DHS have higher mRNA levels of TAP1 and TAP2 and an enhanced capacity for antigen-presenting cells activating dapsone-specific T cells compared with dapsone-tolerant controls. Activation of dapsone-specific T cells was inhibited when TAP function of antigen-presenting cells was impaired. This study shows that epigenetic regulation of TAP1 and TAP2 affects the function of antigen-presenting cells and is a critical factor that mediates the development of DHS.
Topics: Humans; Epigenesis, Genetic; Drug Hypersensitivity Syndrome; Hypersensitivity; Dapsone; HLA-B Antigens; ATP Binding Cassette Transporter, Subfamily B, Member 3
PubMed: 37306379
DOI: 10.1016/j.jid.2022.10.009 -
Crystal Growth & Design Jun 2023The application of computational screening methodologies based on H-bond propensity scores, molecular complementarity, molecular electrostatic potentials, and crystal...
The application of computational screening methodologies based on H-bond propensity scores, molecular complementarity, molecular electrostatic potentials, and crystal structure prediction has guided the discovery of novel cocrystals of dapsone and bipyridine (DDS:BIPY). The experimental screen, which included mechanochemical and slurry experiments as well as the contact preparation, resulted in four cocrystals, including the previously known DDS:4,4'-BIPY (2:1, CC-B) cocrystal. To understand the factors governing the formation of the DDS:2,2'-BIPY polymorphs (1:1, CC-A and CC-B) and the two DDS:4,4'-BIPY cocrystal stoichiometries (1:1 and 2:1), different experimental conditions (such as the influence of solvent, grinding/stirring time, etc.) were tested and compared with the virtual screening results. The computationally generated (1:1) crystal energy landscapes had the experimental cocrystals as the lowest energy structures, although distinct cocrystal packings were observed for the similar coformers. H-bonding scores and molecular electrostatic potential maps correctly indicated cocrystallization of DDS and the BIPY isomers, with a higher likelihood for 4,4'-BIPY. The molecular conformation influenced the molecular complementarity results, predicting no cocrystallization for 2,2'-BIPY with DDS. The crystal structures of CC-A and CC-A were solved from powder X-ray diffraction data. All four cocrystals were fully characterized by a range of analytical techniques, including powder X-ray diffraction, infrared spectroscopy, hot-stage microscopy, thermogravimetric analysis, and differential scanning calorimetry. The two DDS:2,2'-BIPY polymorphs are enantiotropically related, with form B being the stable polymorph at room temperature (RT) and form A being the higher temperature form. Form B is metastable but kinetically stable at RT. The two DDS:4,4'-BIPY cocrystals are stable at room conditions; however, at higher temperatures, CC-A transforms to CC-B. The cocrystal formation enthalpy order, derived from the lattice energies, was calculated as follows: CC-B > CC-A > CC-A.
PubMed: 37304396
DOI: 10.1021/acs.cgd.3c00387 -
Frontiers in Immunology 2023Bullous pemphigoid (BP) is an autoimmune inflammatory skin disease, mostly affecting the elderly population. Therefore, patients often have multiple comorbidities, but... (Review)
Review
Bullous pemphigoid (BP) is an autoimmune inflammatory skin disease, mostly affecting the elderly population. Therefore, patients often have multiple comorbidities, but there is inconsistent data regarding the relationship between HIV-1 infection and BP, which has been rarely reported in combination. Herein, we describe three patients who presented with BP and concomitant HIV-1 infection that was well controlled with modern combined antiretroviral therapy. All patients received topical and oral corticosteroids. Depending on the individual severity, further add-on therapeutics, such as azathioprine, dapsone, doxycycline and the interleukin 4/13 antibody dupilumab, were added to the therapy regimen. All patients recovered from pruritic skin lesions and blistering. The cases are further discussed in the context of the current study landscape. In conclusion, HIV-1 infection shifts the cytokine profile from T-helper type 1 (TH1) towards T-helper type 2 (TH2), resulting in the excessive secretion of distinct cytokines, such as interleukin 4 (IL-4) and interleukin 10 (IL-10). With IL-4 being a main driver in the pathogenesis of BP, HIV-1-positive patients may benefit greatly from targeting IL-4 with monoclonal antibodies.
Topics: Humans; Aged; Pemphigoid, Bullous; Interleukin-4; HIV-1; Blister; Autoimmune Diseases; Interleukin-13
PubMed: 37292193
DOI: 10.3389/fimmu.2023.1179294 -
The American Journal of Tropical... Jul 2023Leprosy is a chronic infection caused by Mycobacterium leprae and Mycobacterium lepromatosis that preferentially compromises peripheral nerve, skin, and mucous...
Leprosy is a chronic infection caused by Mycobacterium leprae and Mycobacterium lepromatosis that preferentially compromises peripheral nerve, skin, and mucous membranes. Colombia achieved the goal of leprosy elimination in 1997. However, in Urabá (Colombia), there has been an increase in leprosy cases beginning in 2020. This case report shows a leprosy relapse 5 decades after the initial infection debuted as a necrotizing erythema nodosum leprosum. Therefore, long-term follow-up of patients with risk factors for relapse is emphasized, especially those treated before the standard of multidrug therapy (dapsone, clofazimine, and rifampin). This case report stresses the importance the importance of clinical follow-up and surveillance of patients with these events of interest for the public health.
Topics: Humans; Leprosy, Lepromatous; Erythema Nodosum; Leprostatic Agents; Drug Therapy, Combination; Leprosy; Recurrence
PubMed: 37253443
DOI: 10.4269/ajtmh.22-0701 -
Frontiers in Pharmacology 2023Drug-induced delayed hypersensitivity reactions (DHRs) is still a clinical and healthcare burden in every country. Increasing reports of DHRs have caught our attention... (Review)
Review
Drug-induced delayed hypersensitivity reactions (DHRs) is still a clinical and healthcare burden in every country. Increasing reports of DHRs have caught our attention to explore the genetic relationship, especially life-threatening severe cutaneous adverse drug reactions (SCARs), including acute generalized exanthematous pustulosis (AGEP), drug reactions with eosinophilia and systemic symptoms (DRESS), Stevens-Johnson syndrome (SJS), and toxic epidermal necrolysis (TEN). In recent years, many studies have investigated the immune mechanism and genetic markers of DHRs. Besides, several studies have stated the associations between antibiotics-as well as anti-osteoporotic drugs (AOD)-induced SCARs and specific human leukocyte antigens (HLA) alleles. Strong associations between drugs and HLA alleles such as co-trimoxazole-induced DRESS and (Odds ratio (OR) = 45), dapsone-DRESS and (OR = 122.1), vancomycin-DRESS and (OR = 403), clindamycin-DHRs and (OR = 55.6), and strontium ranelate (SR)-SJS/TEN and (OR = 25.97) are listed. We summarized the immune mechanism of SCARs, update the latest knowledge of pharmacogenomics of antibiotics- and AOD-induced SCARs, and indicate the potential clinical use of these genetic markers for SCARs prevention in this mini review article.
PubMed: 37180708
DOI: 10.3389/fphar.2023.1183491 -
Cureus Apr 2023Linear IgA disease (LAD) is an uncommon autoimmune blistering disease that has been associated with medications, malignancy, and other autoimmune diseases, such as...
Linear IgA disease (LAD) is an uncommon autoimmune blistering disease that has been associated with medications, malignancy, and other autoimmune diseases, such as ulcerative colitis (UC). In this case report, a patient with a history of UC developed characteristic LAD lesions. While dapsone is considered first-line therapy for LAD, the treatment team opted for an underutilized, plausibly less toxic, and more simplified treatment regimen with sulfasalazine, successfully utilizing the two distinct actions of sulfasalazine's components - sulfapyridine and 5-aminosalicylate (5-ASA) - to concurrently treat both the LAD and UC symptoms. The authors discuss the pathophysiology of LAD and UC and expound on the mechanistic theory of their association. Additionally, the pharmacodynamics of sulfasalazine and considerations of its side effect profile are examined.
PubMed: 37168182
DOI: 10.7759/cureus.37210 -
Indian Journal of Dermatology 2023The clinical presentation of localized pemphigus foliaceus (PF) often involves photo exposed areas. We describe five cases of localized PF, two of which were rare...
The clinical presentation of localized pemphigus foliaceus (PF) often involves photo exposed areas. We describe five cases of localized PF, two of which were rare locations for the disease in non-photo exposed areas, namely the genitalia and back. Patients were treated with topical corticosteroids and calcineurin inhibitors as well as systemic treatment with corticosteroids and dapsone. Each patient responded to treatment, with two achieving remission. No relapses occurred in any of these cases over a mean follow-up time of 3.7 years. A review of the English literature using MEDLINE yielded 18 reported cases of localized PF. Most occurred in photo exposed areas such as the nose, cheeks, scalp, and other areas of the face. Two patients progressed to generalized involvement without treatment. Treatment regimens had much variation and included both topical and systemic agents. Localized PF is rare, and our findings suggest it may be controlled with topical therapy and systemic dapsone.
PubMed: 37151255
DOI: 10.4103/ijd.ijd_324_22 -
Cureus Mar 2023Linear immunoglobulin A (IgA) bullous dermatosis (LABD) is an autoimmune condition with various triggers. Because of the lack of randomized controlled trials on LABD... (Review)
Review
Linear immunoglobulin A (IgA) bullous dermatosis (LABD) is an autoimmune condition with various triggers. Because of the lack of randomized controlled trials on LABD treatment, management options are mostly anecdotal. This paper provides a comprehensive review of treatment options from a literature review of reported treatments to arm clinicians with a guideline for the management of LABD in both pediatric and adult patients as well as those recalcitrant to first-line therapy (dapsone and steroids). We additionally illustrate an algorithm to use for the management of LABD to aid clinicians when faced with unique patient circumstances.
PubMed: 37090290
DOI: 10.7759/cureus.36481