Human Skin as an Ex Vivo Model for Maintaining Mycobacterium leprae and Leprosy Studies.

The in vitro cultivation of M. leprae has not been possible since it was described as causing leprosy, and the limitation of animal models for clinical aspects makes studies on leprosy and bacteria-human host interaction a challenge. Our aim was to standardize the ex vivo skin model (hOSEC) to maintenance and study of M. leprae as an alternative animal model. Bacillary suspensions were inoculated into human skin explants and sustained in DMEM medium for 60 days. Explants were evaluated by RT-PCR-16SrRNA and cytokine gene expression. The viability and infectivity of bacilli recovered from explants (D28 and D60) were evaluated using the Shepard's model. All explants were RT-PCR-16SrRNA positive. The viability and infectivity of recovered bacilli from explants, analyzed after 5 months of inoculation in mice, showed an average positivity of 31%, with the highest positivity in the D28 groups (80%). Furthermore, our work showed different patterns in cytokine gene expression (TGF-ß, IL-10, IL-8, and TNF-α) in the presence of alive or dead bacilli. Although changes can be made to improve future experiments, our results have demonstrated that it is possible to use the hOSEC to maintain M. leprae for 60 days, interacting with the host system, an important step in the development of experimental models for studies on the biology of the bacillus, its interactions, and drug susceptibility.

Peculiar Histological Features of Oral Intravascular Papillary Endothelial Hyperplasia.

A 55-year-old male patient with single and well-circumscribed nodule in the lower lip. Accurate diagnosis is based only on histopathological examination using hematoxylin and eosin and immunohistochemical approach, which a large, organized thrombus within the dilated lumen of a poorly demarcated vein, associated with papillary projections of endothelial proliferation occupying vascular spaces. The final diagnosis was intravascular papillary endothelial hyperplasia (IPEH) associated with a thrombus. Oral IPEH is rare and has historically been difficult to diagnose due to its resemblance to other oral lesions. However, the distinctive histological features of oral IPEH associated with a thrombus now allow for its diagnosis through hematoxylin and eosin staining alone, without the need for additional techniques. Therefore, it is crucial for pathologists to be familiar with these unique morphological features to accurately diagnose oral IPEH and differentiate it from more common benign, malignant, or reactive vascular lesions in the oral cavity.

Prediction of the occurrence of leprosy reactions based on Bayesian networks.

Introduction: Leprosy reactions (LR) are severe episodes of intense activation of the host inflammatory response of uncertain etiology, today the leading cause of permanent nerve damage in leprosy patients. Several genetic and non-genetic risk factors for LR have been described; however, there are limited attempts to combine this information to estimate the risk of a leprosy patient developing LR. Here we present an artificial intelligence (AI)-based system that can assess LR risk using clinical, demographic, and genetic data. Methods: The study includes four datasets from different regions of Brazil, totalizing 1,450 leprosy patients followed prospectively for at least 2 years to assess the occurrence of LR. Data mining using WEKA software was performed following a two-step protocol to select the variables included in the AI system, based on Bayesian Networks, and developed using the NETICA software. Results: Analysis of the complete database resulted in a system able to estimate LR risk with 82.7% accuracy, 79.3% sensitivity, and 86.2% specificity. When using only databases for which host genetic information associated with LR was included, the performance increased to 87.7% accuracy, 85.7% sensitivity, and 89.4% specificity. Conclusion: We produced an easy-to-use, online, free-access system that identifies leprosy patients at risk of developing LR. Risk assessment of LR for individual patients may detect candidates for close monitoring, with a potentially positive impact on the prevention of permanent disabilities, the quality of life of the patients, and upon leprosy control programs.

Patologia da hanseníase e a importância do diagnóstico histopatológico: uma entrevista com Dr. Cleverson Teixeira Soares / Pathology of leprosy and the importance of histopathological diagnosis: an interview with Dr. Cleverson Teixeira Soares

A revista Hansenologia Internationalis tem a honra de entrevistar o Dr. Cleverson Teixeira Soares, médico patologista, responsável pelo Laboratório de Anatomia Patológica do Instituto Lauro de Souza Lima, Bauru, São Paulo, Brasil. Dr. Cleverson é autor do livro Histopathological Diagnosis of Leprosy, publicado em 2021 pela editora Bentham Books, além de relevante publicação de artigos, em periódicos científicos nacionais e internacionais, com impacto nas áreas de patologia e hansenologia. Ele descreve sobre sua trajetória profissional, os desafios para o entendimento da hanseníase em suas múltiplas formas clínicas e como a patologia clássica e molecular tem contribuído para a construção do conhecimento sobre esta doença tão complexa.

Association of CD209 (DC-SIGN) rs735240 SNV with paucibacillary leprosy in the Brazilian population and its functional effects.

BACKGROUND: Leprosy, caused by Mycobacterium leprae, is a public health problem in Brazil that affects peripheral nerves, resulting in physical disabilities. During host-pathogen interactions, the immune response determines leprosy outcomes from a localised (paucibacillary) form to a disseminated (multibacillary) form. The recognition of M. leprae involves the DC-SIGN receptor, which is present on the dendritic cells (DCs) and participates in immune activation. OBJECTIVES: To evaluate the association of polymorphisms in the promoter region of the gene encoding DC-SIGN (CD209) and the clinical form of leprosy, and to investigate its functional effects. METHODS: The study population included 406 leprosy patients from an endemic area in Brazil [310 multibacillary (MB); 96 paucibacillary (PB)]. A functional evaluation based on the effects of the single nucleotide variant (SNV) associated with PB leprosy on the specific immune response was also performed. RESULTS: The GA genotype and the presence of the A allele of rs735240 (-939G>A) were associated with PB leprosy [OR: 2.09 (1.18-3.69) and 1.84 (1.07-3.14), respectively]. Carriers of the A allele showed reduced expression of CD209 and TGF-ß1 in leprosy lesions in comparison with individuals with GG genotype, in addition to a higher response to the Mitsuda test. CONCLUSION: These data suggest that rs735240 influences the immune response against M. leprae and clinical presentation of leprosy.

IFN-γ Mediated Signaling Improves Fungal Clearance in Experimental Pulmonary Mucormycosis.

We established three immunocompetent murine models of pulmonary mucormycosis to determine the involvement of the adaptive immune response in host resistance in pulmonary mucormycosis, a rapidly fatal disease caused mainly by Rhizopus spp. Immunocompetent inbred (C57BL/6, BALB/c) and outbred (Swiss) strains of mice were inoculated with R. oryzae via the intratracheal route. The inoculation resulted in a disseminated infection that spread to the brain, spleen, kidney, and liver. After 7 and 30 days of R. oryzae infection, BALB/c mice showed the lowest fungal load and highest production of IFN-γ and IL-2 by splenocytes. Swiss mice showed a higher fungal load 30 days p.i. and was associated with a weak development of the Th-1 profile. To confirm our findings, R. oryzae-infected IFN-γ-/- mice were evaluated after 60 days, where the mice still showed viable fungi in the lungs. This study showed, for the first time, that pulmonary mucormycosis in three widely used mouse strains resulted in an acute fungal dissemination without immunosuppression whose outcome varies according to the genetic background of the mice. We also identified the partial role of IFN-γ in the efficient elimination of R. oryzae during pulmonary infection.

Association of CD209 (DC-SIGN) rs735240 SNV with paucibacillary leprosy in the Brazilian population and its functional effects

BACKGROUND Leprosy, caused by Mycobacterium leprae, is a public health problem in Brazil that affects peripheral nerves, resulting in physical disabilities. During host-pathogen interactions, the immune response determines leprosy outcomes from a localised (paucibacillary) form to a disseminated (multibacillary) form. The recognition of M. leprae involves the DC-SIGN receptor, which is present on the dendritic cells (DCs) and participates in immune activation. OBJECTIVES To evaluate the association of polymorphisms in the promoter region of the gene encoding DC-SIGN (CD209) and the clinical form of leprosy, and to investigate its functional effects. METHODS The study population included 406 leprosy patients from an endemic area in Brazil [310 multibacillary (MB); 96 paucibacillary (PB)]. A functional evaluation based on the effects of the single nucleotide variant (SNV) associated with PB leprosy on the specific immune response was also performed. RESULTS The GA genotype and the presence of the A allele of rs735240 (-939G>A) were associated with PB leprosy [OR: 2.09 (1.18-3.69) and 1.84 (1.07-3.14), respectively]. Carriers of the A allele showed reduced expression of CD209 and TGF-β1 in leprosy lesions in comparison with individuals with GG genotype, in addition to a higher response to the Mitsuda test. CONCLUSION These data suggest that rs735240 influences the immune response against M. leprae and clinical presentation of leprosy.

Exuberant manifestation of neurofibromatosis type 1 affecting 3 generations: delayed diagnosis and the importance of the multidisciplinary approach.

Neurofibromatosis type 1 (NF1) is an autosomal dominant inherited disorder caused by mutations of chromosome 17. The NF1 clinical diagnosis is based on pre-established criteria, including the presence of cutaneous neurofibromas, café au lait spots, and iris (Lisch) nodules. Early detection and a multidisciplinary approach are essential for the prevention of complications, including problems of function, aesthetics, and self-esteem, as well as the occurrence of malignant transformation. This study reports a case of an exuberant NF1 manifestation diagnosed by a dental surgeon, whose investigation of a family led to the diagnosis of NF1, with different expressivities, in 3 generations.

Murine experimental leprosy: Evaluation of immune response by analysis of peritoneal lavage cells and footpad histopathology.

This study evaluated the immune response of nude and BALB/c mice inoculated in the footpads (FP) with Mycobacterium leprae after 3, 5 and 8 months. At each timepoint peritoneal cells, peripheral blood, FP and popliteal lymph nodes (PLN) were collected. Peritoneal cell cultures were performed to measure the H2 O2 , O2- , NO, IL-2, IL-4, IL-10, IL-12, IFN-γ and TNF levels. Serum levels of anti-PGL-I antibodies were also quantified. The results showed that the infection was progressive in nude mice with bacterial multiplication, development of macroscopic lesions in the FP and presence of bacilli in the PLN at 8 months. In BALB/c mice, the infection reached a plateau of bacillary multiplication at 5 months and regressed at 8 months. Histopathological analysis of FP revealed a mononuclear inflammatory infiltrate with a large number of neutrophils at 5 months, with a higher number in nude mice. At 8 months, the number of neutrophils decreased and the infiltrate was predominantly mononuclear in both mouse strains. There was no H2 O2, O2- , IL-2, IL-4, IL-10 and IFN-γ production in the course of infection in nude mice; however, in BALB/c, O2- and IL-12 production was higher at 5 months and NO, IFN-γ and TNF production was higher at 8 months when there was a decrease in the number of bacilli. The level of anti-PGL-I antibodies was higher in BALB/c mice. Thus, nude and BALB/c mice can be used as experimental models for the study of various aspects of leprosy.

Peripheral nerve tumor, a differential diagnosis with primary neural leprosy: five case reports / Tumor de nervo periférico, diagnóstico diferencial com hanseníase neural primária: relato de cinco casos

From December 1999 to May 2015, five patients with nerve tumors were sent to Lauro de Souza Lima Institute. It was suspected that they suffered from primary neural leprosy towards the tuberculoid clinical form, a prevalence of 4.5:10000 among the new patients assessed during the study period. All of the patients had similar clinical conditions characterized by mononeuropathy with nerve tumor associated with pain, absence of skin lesions and positive Mitsuda reaction. The authors report the main clinical characteristics and complementary tests: immunologic investigation of Mitsuda's reaction and the antigen Phenolic GlicoLipid-1 test (PGL-1), bacilloscopic index, neurophysiologic study and image procedures. All patients were submitted to tumor resection and anatomopathological study. Four out of the five patients were diagnosed with peripheral nerve tumor (one of them with malignant schwannoma, two of them with benign schwannomas and the other with neural fibrolipoma), whereas the fifth patient was diagnosed with tuberculoid leprosy.

No período de dezembro de 1999 a maio de 2015, foram encaminhados ao Instituto Lauro de Souza Lima (ILSL) cinco pacientes com tumoração em nervos suspeitos de hanseníase neural primária (HPN) da forma clinica tuberculoide, uma prevalência de 4,5/10000 entre os casos novos atendidos nesse período. Todos os pacientes apresentavam quadro clínico semelhante caracterizado por mononeuropatia com tumoração do nervo associada à dor, ausência de lesões de pele e reação de Mitsuda positiva. Os autores relatam as principais características clinicas e os exames complementares: investigação imunológica da reação de Mitsuda e o teste do antigeno Glicolipídeo-Fenólico-1, índice baciloscópico, avaliação neurofisiológica e estudos de imagem. Todos os pacientes foram submetidos a ressecção cirúrgica do tumor e estudo anatomopatológico. Dentre os cinco pacientes, quatro foram diagnosticados como tumor de nervo periférico (um Schwannoma maligno, dois Schwannomas benignos e um fibrolipoma neural) e um como hanseníase tuberculoide.

Granulomatous slack skin: a rare subtype of mycosis fungoides.

We report a case of granulomatous slack skin, a rare and indolent subtype of mycosis fungoides. It affects mainly men between the third and fourth decades. It is characterized by hardened and erithematous plaques that mainly affect flexural areas and become pedunculated after some years. Histological examination shows a dense infiltrate of small atypical lymphocytes involving the dermis (and sometimes the subcutaneous tissue) associated with histiocytic and multinucleated giant cells containing lymphocytes and elastic fibers (lymphophagocytosis and elastophagocytosis, respectively). Patients affected by this entity can develop secondary lymphomas. There are several but little effective therapeutic modalities described. Despite the indolent behavior of granulomatous slack skin, its early recognition and continuous monitoring by a dermatologist becomes essential for its management and prevention of an unfavorable outcome.

Lepromatous leprosy simulating rheumatoid arthritis - Report of a neglected disease.

Brazil has the second largest number of leprosy cases in the world; nevertheless, late diagnosis is common. We report the case of a male patient with pain and numbness in both hands and feet for six years with positive rheumatoid factor and anticardiolipin under rheumatoid arthritis treatment for five years. Examination revealed diffuse cutaneous infiltration and leonine facies, characteristic features of lepromatous leprosy. Autoantibodies such as rheumatoid factor and anticardiolipin are markers of rheumatic autoimmune diseases, but their presence is also described in leprosy. We report the present case in order to alert health professionals to remember leprosy, even in areas where the disease is considered eliminated as a public health problem, avoiding misinterpretations of serologic findings and misdiagnosis.

Granulomatous slack skin: a rare subtype of mycosis fungoides

Abstract: We report a case of granulomatous slack skin, a rare and indolent subtype of mycosis fungoides. It affects mainly men between the third and fourth decades. It is characterized by hardened and erithematous plaques that mainly affect flexural areas and become pedunculated after some years. Histological examination shows a dense infiltrate of small atypical lymphocytes involving the dermis (and sometimes the subcutaneous tissue) associated with histiocytic and multinucleated giant cells containing lymphocytes and elastic fibers (lymphophagocytosis and elastophagocytosis, respectively). Patients affected by this entity can develop secondary lymphomas. There are several but little effective therapeutic modalities described. Despite the indolent behavior of granulomatous slack skin, its early recognition and continuous monitoring by a dermatologist becomes essential for its management and prevention of an unfavorable outcome.

Simultaneous analysis of multiple T helper subsets in leprosy reveals distinct patterns of Th1, Th2, Th17 and Tregs markers expression in clinical forms and reactional events.

Leprosy is a chronic infectious disease caused by Mycobacterium leprae. Previous studies have demonstrated that the difference among clinical forms of leprosy can be associated with the immune response of patients, mainly by T helper (Th) and regulatory T cells (Tregs). Then, aiming at clarifying the immune response, the expression of cytokines related to Th1, Th2, Th17 and Tregs profiles were evaluated by qPCR in 87 skin biopsies from leprosy patients. Additionally, cytokines and anti-PGL-1 antibodies were determined in serum by ELISA. The results showed that the expression of various targets (mRNA) related to Th1, Th2, Th17 and Tregs were significantly modulated in leprosy when compared with healthy individuals, suggesting the presence of a mixed profile. In addition, the targets related to Th1 predominated in the tuberculoid pole and side and Th2 and Tregs predominated in the lepromatous pole and side; however, Th17 targets showed a mixed profile. Concerning reactional events, Tregs markers were decreased and IL-15 was increased in reversal reaction and IL-17F, CCL20 and IL-8 in erythema nodosum leprosum, when compared with the respective non-reactional leprosy patients. Additionally, ELISA analysis demonstrated that IL-22, IL-6, IL-10 and anti-PGL-1 antibody levels were significantly higher in the serum of patients when compared with healthy individuals, and IL-10 and anti-PGL-1 antibodies were also increased in the lepromatous pole and side. Together, these results indicate that Th1, Th2 and Th17 are involved in the determination of clinical forms of leprosy and suggest that decreased Tregs activity may be involved in the pathogenesis of reactional events.

Lepromatous leprosy simulating rheumatoid arthritis - Report of a neglected disease

Abstract Brazil has the second largest number of leprosy cases in the world; nevertheless, late diagnosis is common. We report the case of a male patient with pain and numbness in both hands and feet for six years with positive rheumatoid factor and anticardiolipin under rheumatoid arthritis treatment for five years. Examination revealed diffuse cutaneous infiltration and leonine facies, characteristic features of lepromatous leprosy. Autoantibodies such as rheumatoid factor and anticardiolipin are markers of rheumatic autoimmune diseases, but their presence is also described in leprosy. We report the present case in order to alert health professionals to remember leprosy, even in areas where the disease is considered eliminated as a public health problem, avoiding misinterpretations of serologic findings and misdiagnosis.

Ewing's Sarcoma Family Tumors in the Jaws: Case Report, Immunohistochemical Analysis and Literature Review.

Due to the low incidence of the Ewing's Sarcoma (ES) family tumors, the available epidemiology is likely to be unreliable, and at present, there are no standard diagnostic or clinical guidelines outlining their management. This report describes a case of peripheral primitive neuroectodermal tumor (ES/pPNET) which initially mimicked cystic lesions, and describes a comparison between ES and ES/pPNET in the jaws by the World Health Organization classification. This review addressed 63 cases published in the English literature between 1950 and 2016. The majority of cases were ES. Both ES and ES/pPNET mimicked other benign entities such as traumatic, cystic and inflammatory lesions. The patients who died of their disease had a history of metastatic tumors, and primary tumor located in the mandible and maxilla for ES and ES/pPNET, respectively. The differentiation of the ES family tumors from other small blue-cell tumors may be difficult and requires familiarity with histological and immunohistochemical features.