Single-Dose Rifapentine in Household Contacts of Patients with Leprosy.

BACKGROUND: Previous studies have suggested that a single dose of rifampin has protective effects against leprosy in close contacts of patients with the disease. Rifapentine was shown to have greater bactericidal activity against Mycobacterium leprae than rifampin in murine models of leprosy, but data regarding its effectiveness in preventing leprosy are lacking. METHODS: We conducted a cluster-randomized, controlled trial to investigate whether single-dose rifapentine is effective in preventing leprosy in household contacts of patients with leprosy. The clusters (counties or districts in Southwest China) were assigned to one of three trial groups: single-dose rifapentine, single-dose rifampin, or control (no intervention). The primary outcome was the 4-year cumulative incidence of leprosy among household contacts. RESULTS: A total of 207 clusters comprising 7450 household contacts underwent randomization; 68 clusters (2331 household contacts) were assigned to the rifapentine group, 71 (2760) to the rifampin group, and 68 (2359) to the control group. A total of 24 new cases of leprosy occurred over the 4-year follow-up, for a cumulative incidence of 0.09% (95% confidence interval [CI], 0.02 to 0.34) with rifapentine (2 cases), 0.33% (95% CI, 0.17 to 0.63) with rifampin (9 cases), and 0.55% (95% CI, 0.32 to 0.95) with no intervention (13 cases). In an intention-to-treat analysis, the cumulative incidence in the rifapentine group was 84% lower than that in the control group (cumulative incidence ratio, 0.16; multiplicity-adjusted 95% CI, 0.03 to 0.87; P = 0.02); the cumulative incidence did not differ significantly between the rifampin group and the control group (cumulative incidence ratio, 0.59; multiplicity-adjusted 95% CI, 0.22 to 1.57; P = 0.23). In a per-protocol analysis, the cumulative incidence was 0.05% with rifapentine, 0.19% with rifampin, and 0.63% with no intervention. No severe adverse events were observed. CONCLUSIONS: The incidence of leprosy among household contacts over 4 years was lower with single-dose rifapentine than with no intervention. (Funded by the Ministry of Health of China and the Chinese Academy of Medical Sciences; Chinese Clinical Trial Registry number, ChiCTR-IPR-15007075.).

Gastric cancer mesenchymal stem cells promote tumor glycolysis and chemoresistance by regulating B7H3 in gastric cancer cells.

Despite surgical treatment combined with multidrug therapy having made some progress, chemotherapy resistance is the main cause of recurrence and death of gastric cancer (GC). Gastric cancer mesenchymal stem cells (GCMSCs) have been reported to be correlated with the limited efficacy of chemotherapy in GC, but the mechanism of GCMSCs regulating GC resistance needs to be further studied. The gene set enrichment analysis (GSEA) was performed to explore the glycolysis-related pathways heterogeneity across different cell subpopulations. Glucose uptake and lactate production assays were used to evaluate the importance of B7H3 expression in GCMSCs-treated GC cells. The therapeutic efficacy of oxaliplatin (OXA) and paclitaxel (PTX) was determined using CCK-8 and colony formation assays. Signaling pathways altered by GCMSCs-CM were revealed by immunoblotting. The expression of TNF-α in GCMSCs and bone marrow mesenchymal stem cells (BMMSCs) was detected by western blot analysis and qPCR. Our results showed that the OXA and PTX resistance of GC cells were significantly enhanced in the GCMSCs-CM treated GC cells. Acquired OXA and PTX resistance was characterized by increased cell viability for OXA and PTX, the formation of cell colonies, and decreased levels of cell apoptosis, which were accompanied by reduced levels of cleaved caspase-3 and Bax expression, and increased levels of Bcl-2, HK2, MDR1, and B7H3 expression. Blocking TNF-α in GCMSCs-CM, B7H3 knockdown or the use of 2-DG, a key enzyme inhibitor of glycolysis in GC cells suppressed the OXA and PTX resistance of GC cells that had been treated with GCMSCs-CM. This study shows that GCMSCs-CM derived TNF-α could upregulate the expression of B7H3 of GC cells to promote tumor chemoresistance. Our results provide a new basis for the treatment of GC.

Clofazimine-induced cutaneous hyperpigmentation as a source of stigma in the treatment of leprosy: A cross-sectional study.

OBJECTIVES: Cutaneous hyperpigmentation is one of the main adverse effects encountered in patients undergoing leprosy treatment with multidrug therapy (WHO-MDT). This adverse effect has been described as intolerable and capable of contributing to social stigma. The objectives of this study were to quantify the variation in skin colour induced by clofazimine during and after treatment and to assess the related stigma. METHODS: This observational cross-sectional study objectively measured skin colour in 51 patients by reading the individual typology angle (ITA°) with a spectrophotometer, followed by the application of the Stigma Scale of the Explanatory Model Interview Catalogue (EMIC). RESULTS: Skin hyperpigmentation was observed in 100% of the individuals. They showed more negative ITA° values in lesion areas than non-lesion areas, particularly in sun-exposed regions. Clofazimine-induced cutaneous hyperpigmentation was not homogeneous and seemed to follow the lesion locations. The mean EMIC score was 18.8 points. CONCLUSION: All patients presented skin hyperpigmentation caused by clofazimine, detectable through spectrophotometry. Hyperpigmentation strongly impacted the social domain, indicating the intersectionality of disease and skin colour stigma, contributing to the social isolation of these patients. Health authorities should consider the negative impact of clofazimine on treatment adherence.

Role of histopathological, serological and molecular findings for the early diagnosis of treatment failure in leprosy.

BACKGROUND: Treatment failure (TF) in leprosy following multidrug therapy (MDT) presents a significant challenge. The current World Health Organization (WHO) fixed-duration MDT regimen, based on lesion count, might not be adequate. Leprosy lacks clear-cut objective cure criteria, and the predictive value of post-MDT histopathological findings remains uncertain. This study aims to identify predictive factors for TF among leprosy patients who have completed the WHO-recommended MDT. METHODS: An analysis was conducted on 80 individuals from a national leprosy reference center, comprising 40 TF cases (with a mean relapse at 13.0 months) and 40 controls (with a mean of 113.1 months without disease signs). Various epidemiological and clinical-laboratory parameters were assessed post-MDT. RESULTS: In skin samples, the presence of foamy granuloma (OR = 7.36; 95%CI2.20-24.60; p = 0.0012) and histological bacillary index (hBI) ≥ 1+ (OR = 1.55; 95%CI1. 22-1.99; p = 0.0004) were significantly associated with TF, with odds ratios of 7.36 and 1.55, respectively. Individuals who experienced TF had a mean hBI of 3.02+ (SD ± 2.02), while the control group exhibited a mean hBI of 1.8+ (SD ± 1.88). An hBI ≥ 3 + showed a sensitivity of 73% and a specificity of 78% for TF detection (AUC: 0.75; p = 0.0001). Other histopathological features like epithelioid granulomas, and skin changes did not show significant associations (p > 0.05). Additionally, higher anti-phenolic glycolipid-I (anti-PGL-I) ELISA index (EI) levels were linked to a 1.4-fold increased likelihood for TF (OR = 1.4; 95%CI1.13-1.74; p = 0.0019). A mean EI of 4.48 (SD ± 2.80) was observed, with an EI ≥ 3.95 showing a sensitivity of 79% and a specificity of 59% for TF detection (AUC: 0.74; p = 0.0001). Moreover, the presence of Mycobacterium leprae (M. leprae) DNA in real-time polymerase chain reaction (qPCR) was associated with a 3.43-fold higher likelihood of TF. Multivariate regression analysis indicated that concurrent presentation of neural/perineural lymphocytic infiltrate, foamy granuloma, hBI ≥ 1+, and EI ≥ 1 markedly increased the likelihood of TF by up to 95.41%. CONCLUSION: Persistence of nerve-selective lymphocytic infiltrate, foamy granulomas, and bacilli in skin biopsies, and elevated EI post-MDT, may serve as predictive factors for identifying individuals at higher probability of TF.

A case report and literature review: Mycobacterium leprae infection diagnosed by metagenomic next-generation sequencing of cerebrospinal fluid.

BACKGROUND: Leprosy is a chronic infectious disease caused by Mycobacterium leprae (M. leprae) that is responsible for deformities and irreversible peripheral nerve damage and has a broad spectrum of clinical and serological manifestations. Leprosy primarily affects the peripheral nerves and rarely presents with central nervous system involvement. Diagnosing leprosy can still be difficult in some cases, especially when the infection involves uncommon clinical manifestations and extracutaneous sites. Delayed diagnosis and treatment of leprosy may lead to irreversible damage and death. CASE PRESENTATION: We report a case of a 30-year-old female presenting with "repeated high fever with symptoms of headache for 14 days". On the day of admission, physical signs of lost eyebrows and scattered red induration patches all over her body were observed. The patient's diagnosis was based on the clinical characteristics using a combination of metagenomic next-generation sequencing (mNGS) of cerebrospinal fluid (CSF) and slit-skin smear. After confirming Listeria meningitis and multibacillary leprosy with erythema nodosum leprosum (ENL), a type 2 reaction, she was treated with ampicillin sodium, dapsone, rifampicin, clofazimine, methylprednisolone, and thalidomide. At the 1-year follow-up, the frequency and severity of headaches have significantly decreased and a good clinical response with improved skin lesions was found. CONCLUSION: This case highlights the importance of considering leprosy, which is a rare and underrecognized disease, in the differential diagnosis of skin rashes with rheumatic manifestations, even in areas where the disease is not endemic, and physicians should be alerted about the possibility of central nervous system infections. In addition, mNGS can be used as a complementary diagnostic tool to traditional diagnostic methods to enhance the diagnostic accuracy of leprosy.

Microarray data analysis of antileukemic action of Cinnamoylated benzaldehyde LQB-461 in Jurkat cell line.

BACKGROUND: Leukemias stand out for being the main type of childhood cancer in the world. Current treatments have strong side effects for patients, and there is still a high rate of development of resistance to multidrug therapy. Previously, our research group developed a structure-activity study with novel synthetic molecules analogous to LQB-278, described as an essential molecule with in vitro antileukemic action. Among these analogs, LQB-461 stood out, presenting more significant antileukemic action compared to its derivative LQB-278, with cytostatic and cytotoxicity effect by apoptosis, inducing caspase-3, and increased sub-G1 phase on cell cycle analysis. METHODS AND RESULTS: Deepening the study of the mechanism of action of LQB-461 in Jurkat cells in vitro, a microarray assay was carried out, which confirmed the importance of the apoptosis pathway in the LQB-461 activity. Through real-time PCR, we validated an increased expression of CDKN1A and BAX genes, essential mediators of the apoptosis intrinsic pathway. Through the extrinsic apoptosis pathway, we found an increased expression of the Fas receptor by flow cytometry, showing the presence of a more sensitive population and another more resistant to death. Considering the importance of autophagy in cellular resistance, it was demonstrated by western blotting that LQB-461 decreased LC-3 protein expression, an autophagic marker. CONCLUSIONS: These results suggest that this synthetic molecule LQB-461 induces cell death by apoptosis in Jurkat cells through intrinsic and extrinsic pathways and inhibits autophagy, overcoming some mechanisms of cell resistance related to this process, which differentiates LQB-461 of other drugs used for the leukemia treatment.

Novel mutations found in Mycobacterium leprae DNA repair gene nth from central India.

INTRODUCTION: The importance of DNA repair enzymes in maintaining genomic integrity is highlighted by the hypothesis that DNA damage by reactive oxygen/nitrogen species produced inside the host cell is essential for the mutagenesis process. Endonuclease III (Nth), formamidopyrimide (Fpg) and endonuclease VIII (Nei) DNA glycosylases are essential components of the bacterial base excision repair process. Mycobacterium leprae lost both fpg/nei genes during the reductive evolution event and only has the nth (ML2301) gene. This study aims to characterize the mutations in the nth gene of M. leprae strains and explore its correlation with drug-resistance. METHOD: A total of 91 M. leprae positive DNA samples extracted from skin biopsy samples of newly diagnosed leprosy patients from NSCB Hospital Jabalpur were assessed for the nth gene as well as drug resistance-associated loci of the rpoB, gyrA and folP1 genes through PCR followed by Sanger sequencing. RESULTS: Of these 91 patients, a total of two insertion frameshift mutations, two synonymous and seven nonsynonymous mutations were found in nth in seven samples. Sixteen samples were found to be resistant to ofloxacin and one was found to be dapsone resistant as per the known DRDR mutations. No mutations were found in the rpoB region. Interestingly, none of the nth mutations were identified in the drug-resistant associated samples. CONCLUSION: The in-silico structural analysis of the non-synonymous mutations in the Nth predicted five of them were to be deleterious. Our results suggest that the mutations in the nth gene may be potential markers for phylogenetic and epidemiological studies.

A Case of Lepromatous Leprosy (Lucio's Phenomenon) Presenting as Periorbital Edema.

Despite low prevalence of leprosy worldwide, new cases continue to present and require swift evaluation and diagnosis to prevent complications. Here, we describe a case of lepromatous leprosy with Lucio's phenomenon initially presenting with facial and periorbital edema. A 38-year-old Brazilian woman presented to the emergency department with facial swelling and erythema, initially treated as cellulitis. Due to rapid worsening despite broad-spectrum antibiotics, she underwent soft tissue exploration and biopsy due to concern for necrotizing fasciitis. During her course, she also developed retiform purpura of bilateral upper and lower extremities. Periorbital and lower extremity pathological specimens ultimately revealed acid-fast bacilli consistent with Mycobacterium leprae , and the patient improved with multidrug therapy. This case illustrates the diagnostic difficulty of lepromatous leprosy with Lucio's phenomenon, which can initially present with periorbital edema.

Multidrug representation learning based on pretraining model and molecular graph for drug interaction and combination prediction.

MOTIVATION: Approaches for the diagnosis and treatment of diseases often adopt the multidrug therapy method because it can increase the efficacy or reduce the toxic side effects of drugs. Using different drugs simultaneously may trigger unexpected pharmacological effects. Therefore, efficient identification of drug interactions is essential for the treatment of complex diseases. Currently proposed calculation methods are often limited by the collection of redundant drug features, a small amount of labeled data and low model generalization capabilities. Meanwhile, there is also a lack of unique methods for multidrug representation learning, which makes it more difficult to take full advantage of the originally scarce data. RESULTS: Inspired by graph models and pretraining models, we integrated a large amount of unlabeled drug molecular graph information and target information, then designed a pretraining framework, MGP-DR (Molecular Graph Pretraining for Drug Representation), specifically for drug pair representation learning. The model uses self-supervised learning strategies to mine the contextual information within and between drug molecules to predict drug-drug interactions and drug combinations. The results achieved promising performance across multiple metrics compared with other state-of-the-art methods. Our MGP-DR model can be used to provide a reliable candidate set for the combined use of multiple drugs. AVAILABILITY AND IMPLEMENTATION: Code of the model, datasets and results can be downloaded from GitHub (https://github.com/LiangYu-Xidian/MGP-DR). SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

N-2-Hydroxypropylmethacrylamide-Polycaprolactone Polymeric Micelles in Co-delivery of Proteasome Inhibitor and Polyphenol: Exploration of Synergism or Antagonism.

Breast cancer leads to the highest mortality among women resulting in a major clinical burden. Multidrug therapy is more efficient in such patients compared to monodrug therapy. Simultaneous combinatorial or co-delivery garnered significant interest in the past years. Caffeic acid (CFA) (a natural polyphenol) has received growing attention because of its anticarcinogenic and antioxidant potential. Bortezomib (BTZ) is a proteasome inhibitor and may be explored for treating breast cancer. Despite its high anticancer activity, the low water solubility and chemical instability restrict its efficacy against solid tumors. In the present study, we designed and investigated a HP-PCL (N-2-hydroxypropylmethacrylamide-polycaprolactone) polymeric micellar (PMCs) system for the simultaneous delivery of BTZ and CFA in the treatment of breast cancer. The designed BTZ+CFA-HP-PCL PMCs were fabricated, optimized, and characterized for size, zeta potential, surface morphology, and in vitro drug release. Developed nanosized (174.6 ± 0.24 nm) PMCs showed enhanced cellular internalization and cell cytotoxicity in both MCF-7 and MDA-MB-231 cells. ROS (reactive oxygen species) levels were highest in BTZ-HP-PCL PMCs, while CFA-HP-PCL PMCs significantly (p < 0.001) scavenged the ROS generated in 2',7'-dichlorofluorescein diacetate (DCFH-DA) assay. The mitochondrial membrane potential (MMP) assay revealed intense and significant green fluorescence in both types of cancer cells when treated with BTZ-HP-PCL PMCs (p < 0.001) indicating apoptosis or cell death. The pharmacokinetic studies revealed that BTZ-HP-PCL PMCs and BTZ+CFA-HP-PCL PMCs exhibited the highest bioavailability, enhanced plasma half-life, decreased volume of distribution, and lower clearance rate than the pure combination of drugs. In the organ biodistribution studies, the combination of BTZ+CFA showed higher distribution in the spleen and the heart. Overall findings of in vitro studies surprisingly resulted in better therapeutic efficiency of BTZ-HP-PCL PMCs than BTZ+CFA-HP-PCL PMCs. However, the in vivo tumor growth inhibition study performed in tumor-induced mice concluded that the tumor growth was inhibited by both BTZ-HP-PCL PMCs and BTZ+CFA-HP-PCL PMCs (p < 0.0001) more efficiently than pure BTZ and the combination (BTZ+CFA), which may be due to the conversion of boronate ester into boronic acid. Henceforth, the combination of BTZ and CFA provides further indications to be explored in the future to support the hypothesis that BTZ may work with polyphenol (CFA) in the acidic environment of the tumor.

Critical observation of WHO recommended multidrug therapy on the disease leprosy through mathematical study.

Leprosy is a skin disease and it is characterized by a disorder of the peripheral nervous system which occurs due to the infection of Schwann cells. In this research article, we have formulated a four-dimensional ODE-based mathematical model which consists of the densities of healthy Schwann cells, infected Schwann cells, M. leprae bacteria, and the concentration of multidrug therapy (MDT). This work primarily aims on exploring the dynamical changes and interrelations of the system cell populations during the disease progression. Also, evaluating a critical value of the drug efficacy rate of MDT remains our key focus in this article so that a safe drug dose regimen for leprosy can be framed more effectively and realistically. We have examined the stability scenario of different equilibria and the occurrence of Hopf-bifurcation for the densities of our system cell populations with respect to the drug efficacy rate of MDT to gain insight on the precise impact of the efficiency rate on both the infected Schwann cell and the bacterial populations. Also, a necessary transversality condition for the occurrence of the bifurcation has been established. Our analytical and numerical investigations in this research work precisely explores that the process of demyelination, nerve regeneration, and infection of the healthy Schwann cells are the three most crucial factors in the leprosy pathogenesis and to control the M. leprae-induced infection of Schwann cells successfully, a more flexible version of MDT regime with efficacy rate varying in the range η∈(0.025,0.059) for 100-120 days in PB cases and 300 days in MB cases obtained in this research article should be applied. All of our analytical outcomes have been verified through numerical simulations and compared with some existing clinical findings.

Association of PTX3 gene polymorphisms and PTX3 plasma levels with leprosy susceptibility.

BACKGROUND: Pentraxin 3 (PTX3) is a soluble pattern recognition receptor that plays a crucial role in modulating the inflammatory response and activating the complement system. Additionally, plasma PTX3 has emerged as a potential biomarker for various infectious diseases. The aim of this study was to evaluate the association of PTX3 gene polymorphisms and PTX3 plasma levels with susceptibility to leprosy and clinical characteristics. METHODS: Patients with leprosy from a hyperendemic area in the Northeast Region of Brazil were included. Healthy household contacts and healthy blood donors from the same geographical area were recruited as a control group. The rs1840680 and rs2305619 polymorphisms of PTX3 were determined by real-time PCR. Plasma levels of PTX3 were determined by ELISA. RESULTS: A total of 512 individuals were included. Of these, 273 were patients diagnosed with leprosy; 53 were household contacts, and 186 were healthy blood donors. No association was observed between PTX3 polymorphisms and susceptibility to leprosy or development of leprosy reaction or physical disability. On the other hand, plasma levels of PTX3 were significantly higher in patients with leprosy when compared to household contacts (p = 0.003) or blood donors (p = 0.04). It was also observed that PTX3 levels drop significantly after multidrug therapy (p < 0.0001). CONCLUSIONS: Our results suggest that PTX3 may play an important role in the pathogenesis of leprosy and point to the potential use of this molecule as an infection marker.

Leprosy in French Guiana, 2015 to 2021: Dynamics of a Persistent Public Health Problem.

A resurgence of leprosy as a public health problem in French Guiana was reported over the period 2007 to 2014, particularly among Brazilians gold miners. Prolonged multidrug therapy and reversal reactions represent a therapeutic challenge. The objective of this study was to assess the evolution of leprosy in this European overseas territory. All patients with leprosy confirmed in histopathology between 1 January 2015 and 31 December 2021 were included. A total of 86 patients were included, including 64 new cases and 22 previously diagnosed cases. Sixty patients (70%) were male, 6 cases were paediatric. Brazilian gold miners represented 44.1% of reported occupations (15/34). Maroons represented the second community (13 patients, 15%). Multibacillary and paucibacillary forms were found in 53 (71%) and 22 (29%) patients, respectively. The annual prevalence never exceeded the threshold of 1/10,000. The mean incidence and prevalence were significantly lower than during the period 2007 to 2014 (p < 0.0001). Reversal reactions were found in 29 patients and almost always required a long course of steroids. Infliximab allowed a reduction in the length of treatment with steroids in 2/2 cases. In conclusion, the prevalence of leprosy has decreased significantly in French Guiana, but remains driven by the population of illegal gold miners. Anti-tumour necrosis factor (anti-TNF) drugs represent a promising option in the management of reversal reactions.

Different Efflux Pump Systems in Acinetobacter baumannii and Their Role in Multidrug Resistance.

Several infections, such as pneumonia, urinary tract infections (UTIs), as well as bloodstream, skin, and soft tissue infections, are caused by Acinetobacter baumannii, a nosocomial pathogen and Gram-negative coccobacillus. Due to its resistance to a variety of medications, multidrug therapy, and occasionally pan therapies, this bacterium is a huge public health concern. Drug resistance is a big worry not only in A. baumannii, but it is also a major challenge in many other diseases. Antibiotic resistance, biofilm development, and genetic alterations are all linked to variables like the efflux pump. Efflux pumps are transport proteins involved in the extrusion of hazardous substrates from within cells into the external environment (including nearly all types of therapeutically relevant antibiotics). Both Gram-positive and Gram-negative bacteria, as well as eukaryotic organisms, contain these proteins. Efflux pumps may be specialized for a single substrate or can transport a variety of structurally dissimilar molecules (including antibiotics of many classes); these pumps have been linked to multiple drug resistance (MDR). There are five primary families of efflux transporters in the prokaryotic kingdom: MF (major facilitator), MATE (multidrug and toxic efflux), RND (resistance-nodulation-division), SMR (small multidrug resistance), and ABC (ATP-binding cassette). The efflux pumps and their types as well as the mechanisms of an efflux pump involved in multidrug resistance in bacteria have been discussed here. The main focus is on the variety of efflux pumps commonly found in A. baumannii, along with their mechanism by which they make this bacteria drug resistant. The efflux-pump-inhibitor-based strategies that are significant in targeting efflux pumps in A. baumannii have also been discussed. The connection of biofilm and bacteriophage with the efflux pump can prove as an efficient strategy for targeting efflux-pump-based resistance in A. baumannii.

Progressive neuropathy in patients with lepromatous leprosy after multidrug therapy.

BACKGROUND: The lepromatous pole is a stigmatising prototype for patients with leprosy. Generally, these patients have little or no symptoms of peripheral nerve involvement at the time of their diagnosis. However, signs of advanced peripheral neuropathy would be visible during the initial neurological evaluation and could worsen during and after multidrug therapy (MDT). Disabilities caused by peripheral nerve injuries greatly affect these patients' lives, and the pathophysiological mechanisms underlying nerve damage remain unclear. OBJECTIVES: To evaluate the outcome of peripheral neuropathy in patients with lepromatous leprosy (LL) and persistent neuropathic symptoms years after completing MDT. METHODS: We evaluated the medical records of 14 patients with LL who underwent nerve biopsies due to worsening neuropathy at least four years after MDT. FINDINGS: Neuropathic pain developed in 64.3% of the patients, and a neurological examination showed that most patients had alterations in the medium- and large-caliber fibers at the beginning of treatment. Neurological symptoms and signs deteriorated despite complete MDT and prednisone or thalidomide use for years. Nerve conduction studies showed that sensory nerves were the most affected. MAIN CONCLUSIONS: Patients with LL can develop progressive peripheral neuropathy, which continues to develop even when they are on long-term anti-inflammatory and immunosuppressive therapy.

Mycobacterium leprae's Infective Capacity Is Associated with Activation of Genes Involved in PGL-I Biosynthesis in a Schwann Cells Infection Model.

Peripheral nerves and Schwann cells (SCs) are privileged and protected sites for initial colonization, survival, and spread of leprosy bacillus. Mycobacterium leprae strains that survive multidrug therapy show a metabolic inactivation that subsequently induces the recurrence of typical clinical manifestations of leprosy. Furthermore, the role of the cell wall phenolic glycolipid I (PGL-I) in the M. leprae internalization in SCs and the pathogenicity of M. leprae have been extensively known. This study assessed the infectivity in SCs of recurrent and non-recurrent M. leprae and their possible correlation with the genes involved in the PGL-I biosynthesis. The initial infectivity of non-recurrent strains in SCs was greater (27%) than a recurrent strain (6.5%). In addition, as the trials progressed, the infectivity of the recurrent and non-recurrent strains increased 2.5- and 2.0-fold, respectively; however, the maximum infectivity was displayed by non-recurrent strains at 12 days post-infection. On the other hand, qRT-PCR experiments showed that the transcription of key genes involved in PGL-I biosynthesis in non-recurrent strains was higher and faster (Day 3) than observed in the recurrent strain (Day 7). Thus, the results indicate that the capacity of PGL-I production is diminished in the recurrent strain, possibly affecting the infective capacity of these strains previously subjected to multidrug therapy. The present work opens the need to address more extensive and in-depth studies of the analysis of markers in the clinical isolates that indicate a possible future recurrence.

Leprosy in the Heartland.

BACKGROUND: Mycobacterium leprae is an acid fast bacterium that causes leprosy, also known as Hansen's disease. M. leprae spreads primarily through respiratory droplets and skin contact, and widespread migration of the human population may lead to infection in non-endemic areas. Leprosy mainly affects the skin, peripheral nerves, mucosa of the upper respiratory tract, and the eyes, presenting as a spectrum of disease based on the host immune response consisting of skin lesions, areas of anesthesia, local tissue destruction, and even blindness or glomerulonephritis in severe cases. CASE DESCRIPTION: We describe a case of leprosy presenting in a South Dakota resident. Before this case, leprosy had not been reported in South Dakota in 11 years. The patient presented with chronic skin lesions with areas of anesthesia on her right knee and left elbow. Physical exam was unremarkable aside from the skin lesions, which had areas of decreased sensation over the involved skin. Biopsy of the lesions was positive for noncaseating granulomas with lymphocytic infiltrate that were acid-fast bacillus positive. The biopsy was sent to the National Hansen's Disease Program for further molecular testing, which confirmed M. leprae infection. The patient underwent 12 months of dapsone 100 mg po qd and rifampin 600 mg po qd per U.S. guidelines from the National Hansen's Disease Program Clinical Center. The patient responded well to treatment until developing a reversal reaction after nine months, which was resolved with corticosteroid treatment. Both dermatology and infectious disease continue to follow the patient, and she continues to do well with no evidence of recurrence of active infection or evidence of reversal reaction. CONCLUSIONS: It is important that clinicians be aware of the possibility of uncommon presentations/diseases such as leprosy in areas where it is extremely rare (such as South Dakota) due to immigration and travel among patients. The rarity of leprosy in areas like South Dakota, in addition to its potential for misdiagnosis, may lead to delay of treatment in the patient. Delays in treatment can allow progression of the disease causing skin lesions and possible nerve damage.

Antimicrobial Resistance among Leprosy Patients in Brazil: Real-World Data Based on the National Surveillance Plan.

Brazil ranks second among countries for new cases and first for relapse cases of leprosy worldwide. The Mycobacterium leprae Resistance Surveillance Plan was established. We aimed to present the results of a 2-year follow-up of the National Surveillance Plan in Brazil. A cross-sectional study of leprosy cases was performed to investigate antimicrobial resistance (AMR) in Brazil from October 2018 to September 2020. Molecular screening targeting genes related to dapsone (folP1), rifampin (rpoB), and ofloxacin resistance (gyrA) was performed. During the referral period, 63,520 active leprosy patients were registered in Brazil, and 1,183 fulfilled the inclusion criteria for molecular AMR investigation. In total, only 16 (1.4%) patients had genetic polymorphisms associated with AMR. Of these, 8 (50%) had cases of leprosy relapse, 7 (43.8%) had cases of suspected therapeutic failure with standard treatment, and 1 (6.2%) was a case of new leprosy presentation. M. leprae strains with AMR-associated mutations were found for all three genes screened. Isolates from two patients showed simultaneous resistance to dapsone and rifampin, indicating multidrug resistance (MDR). No significant relationship between clinical variables and the presence of AMR was identified. Our study revealed a low frequency of AMR in Brazil. Isolates were resistant mainly to dapsone, and a very low number of isolates were resistant to rifampin, the main bactericidal agent for leprosy, or presented MDR, reinforcing the importance of the standard World Health Organization multidrug therapy. The greater frequency of AMR among relapsed patients supports the need to constantly monitor this group.

Mycobacterial skin infection.

PURPOSE OF REVIEW: The aim of this article is to review the most recent evidences concerning mycobacterial skin infections, limiting the period of literature research to 2020--2021. RECENT FINDINGS: Mycobacterial skin infections include a heterogeneous group of cutaneous diseases.Cutaneous tuberculosis is usually the result of hematogenous dissemination or spread from underlying foci and it must be distinguished from tuberculids, resulting from the immunological reaction to Mycobacterium tuberculosis antigens. Leprosy prevalence was drastically reduced after introduction of multidrug therapy in the 1980 s, but cases are still reported due to underdiagnosis, and animal and environmental reservoirs. Recent advances concentrate in the diagnostic field. Specific guidelines for the treatment of nontuberculous mycobacteria skin infections are missing and surgical procedures may be required. Prognosis is better as compared to nontuberculous mycobacteria lung disease. Rapid laboratory-confirmed diagnosis of Buruli ulcer may be achieved by the IS2404 PCR. Among new drugs, telacebec is promising in terms of potency, shorter duration and tolerability in animal studies. A clinical trial in humans is planned. SUMMARY: Mycobacterial cutaneous lesions are nonpathognomonic and clinical suspicion must be confirmed by culture or molecular detection. Long-course multidrug treatment is required based on susceptibility tests. Surgical intervention may also be required. Rehabilitation and psychosocial support reduce long-term physical and mental consequences mostly in Buruli ulcer and leprosy.

Treatment strategy with multidrug therapy and tonsillectomy pulse therapy for childhood-onset severe IgA nephropathy.

BACKGROUND: IgA nephropathy is a typical chronic glomerulonephritis that tends to occur in childhood. METHOD: We reviewed the report on pathogenesis, treatment strategy with multidrug therapy and tonsillectomy pulse therapy for childhood-onset severe IgA nephropathy to clarify the pathophysiology and treatment of IgA nephropathy in childhood. RESULTS: In recent years, it has been found that the pathogenesis at onset is associated with aberrant glycosylation at the IgA1 hinge. Given this genetic background, the aberrantly glycosylated IgA1immune complex produced by antigen-stimulated T cells and B cells is deposited in the glomeruli. Inflammation is induced via activation of the complement, macrophages and mesangial cells, and glomerular damage progresses thereafter. Treatment is selected according to the severity of IgA nephropathy. In order to prevent the development of renal damage, it is important to control the associated immune responses. For severe IgA nephropathy, in particular, multidrug therapy with prednisolone, immunosuppressants, and angiotensin enzyme synthesis inhibitors and tonsillectomy methylprednisolone pulse therapy are now performed- and, as a result, the number of renal deaths has decreased and the long-term prognosis has improved. CONCLUSION: The prognosis of IgA nephropathy is improving. In the future, it will be important to develop a treatment method that takes into consideration the fact that children are in their growth and development stage and, therefore, seeks to minimizes side effects.