Lobomycosis Research Articles

Macrophage immunophenotypes in Jorge Lobo’s disease and lepromatous leprosy- A comparative study

Jorge Lobo's disease (JLD) and lepromatous leprosy (LL) share several clinical, histological and immunological features, especially a deficiency in the cellular immune response. Macrophages participate in innate and adaptive inflammatory immune responses, as well as in tissue regeneration and repair. Macrophage function deficiency results in maintenance of diseases. M1 macrophages produce pro-inflammatory mediators and M2 produce anti-inflammatory cytokines. To better understand JLD and LL pathogenesis, we studied the immunophenotype profile of macrophage subtypes in 52 JLD skin lesions, in comparison with 16 LL samples, using a panmacrophage (CD68) antibody and selective immunohistochemical markers for M1 (iNOS) and M2 (CD163, CD204) responses, HAM56 (resident/fixed macrophage) and MAC 387 (recently infiltrating macrophage) antibodies.We found no differences between the groups regarding the density of the CD163, CD204, MAC387+ immunostained cells, including iNOS, considered a M1 marker. But HAM56+ cell density was higher in LL samples. By comparing the M2 and M1 immunomarkers in each disease separately, some other differences were found. Our results reinforce a higher M2 response in JLD and LL patients, depicting predominant production of anti-inflammatory cytokines, but also some distinction in degree of macrophage activation. Significant amounts of iNOS + macrophages take part in the immune milieu of both LL and JLD samples, displaying impaired microbicidal activity, like alternatively activated M2 cells.

Skin fibrosis associated with keloid, scleroderma and Jorge Lobo's disease (lacaziosis): An immuno-histochemical study.

Fibrosis is a common pathophysiological response of many tissues and organs subjected to chronic injury. Despite the diverse aetiology of keloid, lacaziosis and localized scleroderma, the process of fibrosis is present in the pathogenesis of all of these three entities beyond other individual clinical and histological distinct characteristics. Fibrosis was studied in 20 samples each of these three chronic cutaneous inflammatory diseases. An immunohistochemical study was carried out to explore the presence of α-smooth muscle actin (α-SMA) and vimentin cytoskeleton antigens, CD31, CD34, Ki67, p16; CD105, CD163, CD206 and FOXP3 antigens; and the central fibrotic cytokine TGF-β. Higher expression of vimentin in comparison to α-SMA in all three lesion types was found. CD31- and CD34-positive blood vessel endothelial cells were observed throughout the reticular dermis. Ki67 expression was low and almost absent in scleroderma. p16-positive levels were higher than ki67 and observed in reticular dermis of keloidal collagen in keloids, in collagen bundles in scleroderma and in the external layers of the granulomas in lacaziosis. The presence of α-actin positive cells and rarely CD34 positive cells, observed primarily in keloids, may be related to higher p16 antigen expression, a measure of cell senescence. Low FOXP3 expression was observed in all lesion types. CD105-positive cells were mainly found in perivascular tissue in close contact with the adventitia in keloids and scleroderma, while, in lacaziosis, these cells were chiefly observed in conjunction with collagen deposition in the external granuloma layer. We did not find high involvement of CD163 or CD206-positive cells in the fibrotic process. TGF-β was notable only in keloid and lacaziosis lesions. In conclusion, we have suggested vimentin to be the main myofibroblast general marker of the fibrotic process in all three studied diseases, while endothelial-to-mesenchymal transition (EndoMT) and mesenchymal stem cells (MSCs) and M2 macrophages may not play an important role.

P308 Jorge lobo's disease in brazil: a new recognized reservoir?

Poster session 2, September 22, 2022, 12:30 PM - 1:30 PMLobomycosis (lacaziosis) is a chronic subcutaneous disease caused by the uncultivated fungus Lacazia loboi. The disease was first described in 1931 by Jorge Lobo in Brazil and has been reported in South and Central America. Lobomycosis is a rare disease that affects certain geographic regions, mainly in countries of low socioeconomic status, but its prevalence among indigenous people in Brazil is exceptionally high. The state of Maranhão is located in the northeast region of the country and there are rare clinical reports of imported cases of the disease in our region. This is the first published series of autochthonous cases of lacaziosis in Maranhão.ObjectiveTo describe seven cases of Lacazia loboi infections in immunocompetent patients in an endemic area for other subcutaneous mycoses.MethodsWe retrospectively reviewed the medical records of all patients who developed Jorge Lobo's diseases in a new area recognized as a potential environment reservoir. An incident case was defined as a patient who developed proven lacaziosis based on the presence of topical fungal elements in the tissue on histopathology or mycologic direct exam. Epidemiological and clinical data of all cases of lacaziosis were collected using a standard clinical form.ResultsIn the period from 2000 to 2021, seven patients were identified. All cases were diagnosed by histopathology and direct mycological examination of the lesions. A total of 6 out of 7 (85.7%) patients were men and the mean age was 57 years (52-70 years). The median time between onset of infection symptoms and diagnosis was ˃2 years in 6 patients, with 15 years of symptoms duration in patient 7. All patients reported having worked with agricultural activities before. A total of 50% of patients were diagnosed with localized lesions and the other half with disseminated lesions. Subcutaneous lesions involved the upper limbs (4/6; 66.6%), ears (2/6; 33.3%), lower limbs (1/6; 16.6%), and trunk (1/6; 16.6%). All patients exhibited nodules as a dominant pattern of skin lesion, sometimes coalescing with the tumor's appearance. Regarding treatment, a combination of itraconazole and clofazimine therapy was added to all patients. Surgical excision was possible only in 2 episodes due to the limited availability of this procedure at the site. Cure was documented in 2 cases, with no recurrence to date.ConclusionThe present series represents the first and largest collection of case studies of lacaziosis in Maranhão state, with all cases classified as autochthonous. Lacaziosis involves mainly adult males with different occupational risks such as agricultural labor, and other workers exposed to contaminated soil and plant materials. Few data are available to support suggested therapy with itraconazole and clofazime. Excision surgery is important for treatment due to the absence of clinical trials in the medical literature. Epidemiological surveillance studies of new cases of lacasiozis in Maranhão are important for mapping this new reservoir and developing public policies for diagnosis and treatment.

A Case of Cutaneous T Cell Lymphoma Masquerading as Keloidal Blastomycosis Treated with CHOP Regimen.

A Case of Cutaneous T Cell Lymphoma Masquerading as Keloidal Blastomycosis Treated with CHOP Regimen.

Skin diseases in indigenous population: retrospective epidemiological study at Xingu Indigenous Park (XIP) and review of the literature.

Skin diseases among indigenous populations have been poorly described in the literature. Risk factors linked to habits, cultural practices, genetics, and environmental characteristics can influence the frequency and clinical presentation of these diseases. This was a cross-sectional study conducted through a review of dermatological medical records. Data were obtained over three visits to Xingu Indigenous Park (XIP). Main dermatoses were compared by gender, age, ethnicity, and village. Diseases were classified into four groups: infectious, inflammatory, neoplastic, and other. Of the 398 patients included in the study, 54.2% were female. The participants ranged in age from 1 to 75 years (median, 10 years). The predominant ethnic group was Caiabi (49.7%), followed by Ikpeng (14.3%) and Kamaiurá (10.0%). The primary village studied was Diauarum, followed by Moigú and Morena. Infectious dermatoses were the most frequent (43.8%), followed by inflammatory (33.7%), neoplastic (15.5%), and other skin diseases (7.0%). Infectious diseases were predominant in Caiabi and Kamaiurá Indians, whereas inflammatory skin diseases were more frequent in Ikpeng and Juruna populations. We also observed a high frequency of malignancy in the Ikpeng and Trumai ethnic groups. Infectious skin diseases, except for fungal infections, were frequent in younger age groups. This trend was not replicated for neoplastic skin diseases. Uncommon dermatoses such as Heck's disease, lichen striatus, and aquagenic urticaria were also observed. Jorge Lobo's disease was not included in this analysis. Improved knowledge of the distribution of common dermatoses among different ethnic groups and villages in XIP will aid in the prevention of skin infections and skin cancer. This improved knowledge will also allow the development of skin disease guidelines that can help local indigenous health professionals.

The cytotoxic T cells may contribute to thein situimmune response in Jorge Lobo's Disease human lesions

Jorge Lobo's Disease (JLD) is a cutaneous chronic granulomatous disease caused by the pathogenic fungus Lacazia loboi. It is characterized by a granulomatous reaction with multinucleated giant cells and high number of fungal cells. In order to contribute to the comprehension of immune mechanisms in JLD human lesions, we studied the cytotoxic immune response, focusing on TCD8+ and NK cells, and granzyme B. Forty skin biopsies of lower limbs were selected and an immunohistochemistry protocol was developed to detect CD8+ T cells, NK cells and Granzyme B. In order to compare the cellular populations, we also performed a protocol to visualize TCD4+ cells. Immunolabeled cells were quantified in nine randomized fields in the dermis. Lesions were characterized by inflammatory infiltrate of macrophages, lymphocytes, epithelioid and multinucleated giant cells with intense number of fungal forms. There was a prevalence of CD8 over CD4 cells, followed by NK cells. Our results suggest that in JLD the cytotoxic immune response could represent another important mechanism to control Lacazia loboi infection. We may suggest that, although CD4+ T cells are essential for host defense in JLD, CD8+ T cells could play a role in the elimination of the fungus.

Analysis of Immune Response Markers in Jorge Lobo's Disease Lesions Suggests the Occurrence of Mixed T Helper Responses with the Dominance of Regulatory T Cell Activity.

Jorge Lobo’s disease (JLD) is a chronic infection that affects the skin and subcutaneous tissues. Its etiologic agent is the fungus Lacazia loboi. Lesions are classified as localized, multifocal, or disseminated, depending on their location. Early diagnosis and the surgical removal of lesions are the best therapeutic options currently available for JLD. The few studies that evaluate the immunological response of JLD patients show a predominance of Th2 response, as well as a high frequency of TGF-β and IL-10 positive cells in the lesions; however, the overall immunological status of the lesions in terms of their T cell phenotype has yet to be determined. Therefore, the objective of this study was to evaluate the pattern of Th1, Th2, Th17 and regulatory T cell (Treg) markers mRNA in JLD patients by means of real-time PCR. Biopsies of JLD lesions (N = 102) were classified according to their clinical and histopathological features and then analyzed using real-time PCR in order to determine the expression levels of TGF-β1, FoxP3, CTLA4, IKZF2, IL-10, T-bet, IFN-γ, GATA3, IL-4, IL-5, IL-13, IL-33, RORC, IL-17A, IL-17F, and IL-22 and to compare these levels to those of healthy control skin (N = 12). The results showed an increased expression of FoxP3, CTLA4, TGF-β1, IL-10, T-bet, IL-17F, and IL-17A in lesions, while GATA3 and IL-4 levels were found to be lower in diseased skin than in the control group. When the clinical forms were compared, TGF-β1 was found to be highly expressed in patients with a single localized lesion while IL-5 and IL-17A levels were higher in patients with multiple/disseminated lesions. These results demonstrate the occurrence of mixed T helper responses and suggest the dominance of regulatory T cell activity, which could inhibit Th-dependent protective responses to intracellular fungi such as L. loboi. Therefore, Tregs may play a key role in JLD pathogenesis.

THE RELEVANCE OF NUTRITIONAL STATUS AND HISTOPATHOLOGICAL FINDINGS ON THE INFECTIOUS PROCESS OF BALB/C MICE INOCULATED WITH Lacazia loboi.

SUMMARYThe aim of this study was to evaluate the effects of the protein-calorie malnutrition in BALB/c isogenic mice infected with Lacazia loboi, employing nutritional and histopathological parameters. Four groups were composed: G1: inoculated with restricted diet, G2: not inoculated with restricted diet, G3: inoculated with regular diet, G4: not inoculated with regular diet. Once malnutrition had been imposed, the animals were inoculated intradermally in the footpad and after four months, were sacrificed for the excision of the footpad, liver and spleen. The infection did not exert great influence on the body weight of the mice. The weight of the liver and spleen showed reduction in the undernourished groups when compared to the nourished groups. The macroscopic lesions, viability index and total number of fungi found in the footpads of the infected mice were increased in G3 when compared to G1. Regarding the histopathological analysis of the footpad, a global cellularity increase in the composition of the granuloma was observed in G3 when compared to G1, with large numbers of macrophages and multinucleated giant cells, discrete numbers of lymphocytes were present in G3 and an increase was observed in G1. The results suggest that there is considerable interaction between Jorge Lobo's disease and nutrition.

Th17 and regulatory T cells contribute to the in situ immune response in skin lesions of Jorge Lobo's disease.

Jorge Lobo's disease (JLD) is a chronic granulomatous mycosis described in various Latin American countries. The main objective of the present study was to investigate the possible role of Th17 and Foxp3+ Treg cells in the pathogenesis of Jorge Lobo's disease. Human skin biopsies were submitted to an immunohistochemistry protocol to detect Foxp3, interleukin (IL)-1beta, CD25, IL-6, IL-17, and IL-23. The epidermis presented acanthosis, hyperkeratosis, and frequent presence of fungi. The dermis presented inflammatory infiltrate comprising macrophages, lymphocytes, epithelioid and multinucleated cells, and an intense number of fungi. Foxp3+ Treg cells and IL-17+ cells were visualized in lymphocytes in the inflammatory infiltrate. IL-1, IL-2R (CD25), IL-6, and IL-23 were visualized in the dermis, intermingled with fungal cells, permeating or participating of the granuloma. Following IL-17, the most prominent cytokine was IL-6. IL-23 and cells expressing CD25 were present in fewer number. The comparative analysis between IL-17 and Foxp3 demonstrated a statistically significant increased number of IL-17+ cells. Th17 cells play a role in the immune response of JLD. IL-1beta and IL-6 added to the previously described increased number of TGF-beta would stimulate such pattern of response. Th17 cells could be present as an effort to modulate the local immune response; however, high levels of a Th17 profile could overcome the role of Treg cells. The unbalance between Treg/Th17 cells seems to corroborate with the less effective immune response against the fungus.

Nutritional status and immune response in murine experimental Jorge Lobo's disease.

There are no studies investigating the role of nutritional status and immunity associated with Jorge Lobo's disease. The objective of this study was to evaluate the effects of protein-calorie malnutrition on the immune response of BALB/c mice inoculated with Lacazia loboi. In this study,the animals were divided into four groups: G1: inoculated with restricted diet, G2: not inoculated with restricted diet, G3: inoculated with regular diet, G4: not inoculated with regular diet. The animals of groups G1 and G2 were submitted to malnutrition for 20 days and once installed the animals were inoculated intradermally into the footpad. After 4 months, they were euthanised for the isolation of peritoneal lavage cells and removal of the footpad. The production of IL-2, IL-4, IL-10, IL-12, IFN-γ, TNF-α, H2 O2 and nitric oxide (NO) was evaluated in the peritoneal lavage cells. The footpad was evaluated regarding the size of macroscopic lesions, number of fungi and viability index. The results showed that the infection did not exert great influence on the body weight of the mice and previous malnutrition was an unfavourable factor for viability index, number of fungi, macroscopic lesion size in the footpad and production of H2 O2 , NO, IL-12, IL-10 and IFN-γ, suggesting that malnutrition significantly altered fungal activity and peritoneal cells. The results suggest considerable interaction between nutrition and immunity in Jorge Lobo's disease.

DNA damage in BALB/c mice infected with Lacazia loboi and its relation to nutritional status.

BackgroundJorge Lobo’s disease, also known as lacaziosis, is a cutaneous-subcutaneous mycosis with chronic evolution. It is caused by the fungus Lacazia loboi. Herein we report a study that relates the genotoxicity caused by L. loboi in isogenic mice with nutritional status, through a normal or restricted diet.MethodsDNA damage was assessed in the peripheral blood by the comet assay (tail intensity).ResultsThe results for leukocytes showed increases in the mean tail intensity in mice under dietary restriction, in infected mice under dietary restriction and in infected mice ingesting a normal diet.ConclusionThese results indicate that dietary restriction and L. loboi infection may increase DNA damage levels in mice, as detected by the comet assay.

Study of murine experimental Jorge Lobo's disease by analysis of peritoneal lavage cells and footpad histopathology: early versus chronic lesions.

The murine model of Jorge Lobo's disease is characterized by histological alterations similar to those seen in human disease, including a large number of viable fungi. This study evaluated the immune response of mice with early and late macroscopic lesions (5 and 13 months post-inoculation [p.i.], respectively) by the analysis of peritoneal lavage cells and footpad (FP) histology. The FP of mice were inoculated with 1 × 10(6) fungi (viability index of 41%). At 5 and 13 months p.i., the granuloma mainly consisted of macrophages and multinucleated giant cells, but a larger number of neutrophils was observed at 5 months and lymphocytes at 13 months. The number of fungi in the FP and fungal viability were 1.8 ± 1.1 × 10(6) fungi/ml and 38.5% at 5 months p.i. and 30.8 ± 11.7 × 10(6) fungi/ml and 9% at 13 months (P < .05). Higher production of H₂O₂, O₂(-), IL-10, and TNF-α were observed at 13 months (P < .05), but there was no significant difference in the production of NO, IL-2, IL-4, IL-12 and IFN-γ. The results showed significant differences between early and late lesions and support the use of BALB/c mice for evaluation of the different phases of infection.

Jorge Lobo's disease: immunohistochemical characterization of dendritic cells in cutaneous lesions.

Jorge Lobo's disease (JLD) is a cutaneous chronic mycosis caused by Lacazia loboi. We studied Factor XIIIa + dermal dendrocytes (FXIIIa + DD), Langerhans cells (LC) through the expression of langerin and the expression of S100 protein. A total of 41 biopsies and 10 normal skins (control) were developed with a polymer-based immunohistochemical method. Lesions presented infiltrate comprising macrophages, some asteroid corpuscles, lymphocytes, multinucleated giant cells and a large number of fungi. LCs presented short dendrites and were scarcely distributed. Dermal langerin + cells were detected in nine JLD lesions. FXIIIa + DD were hypertrophic, visualized in the inflammatory infiltrate of JLD lesions. Cells S100+ were present in JLD and control group with a similar number of cells. A total of 14 specimens did not express FXIIIa, and this considerable number probably contributed to the statistical similarity with the control group. The results indicate that LCs are present in the immune response against Lacazia loboi. Some dermal langerin + cells could be another subset of dendritic cells. Our data indicate changes of LCs in JLD cutaneous lesions and present, for the first time, results that show langerin + cells in the dermis and corroborate previous observations on the participation of FXIIIa + DD in the in situ immune response in JLD.

Analysis of microvasculature phenotype and endothelial activation markers in skin lesions of lacaziosis (Lobomycosis)

Jorge Lobo's disease is a rare mycosis characterized by chronic inflammation, which causes skin lesions in the absence of visceral dissemination. The disease occurs mainly in hot and humid climates and most cases have been registered in the Brazilian Amazon region. This study investigated possible microvascular alterations in skin lesions caused by infection with Lacazia loboi which may interfere with the clinical progression of the disease. Immunohistochemistry was used to evaluate the density of blood and lymphatic vessels, as well as expression of the cell adhesion molecules ICAM-1, VCAM-1 and E-selectin. The results showed a reduced number of blood (62.66 ± 20.30 vessels/mm2) and lymphatic vessels (3.55 ± 5.84 vessels/mm2) in Jorge Lobo's disease when compared to control skin (169.66 ± 66.38 blood vessels/mm2 and 8 ± 2.17 lymphatic vessels/mm2). There were a larger number of vessels expressing ICAM-1 (27.58 ± 15.32 vessels/mm2) and VCAM-1 (7.55 ± 6.2 vessels/mm2). No difference was observed in the expression of E-selectin (4.66 ± 11 vessels/mm2). Taken together, the results indicate changes in the local microvasculature which may interfere with the development of an efficient cell-mediated immune response and may explain restriction of the fungus to the site of injury.

Jorge Lobo's disease: a case of keloidal blastomycosis (lobomycosis) in a nonendemic area.

Lobomycosis or lacaziosis is a chronic subcutaneous fungal infection, caused by the fungus Lacazia loboi, which is phylogenetically related to Coccidioides, Blastomyces, Histoplasma, and Paracoccidioides. The disease was first recognized in 1931 by Jorge Lobo, who found the disease to be a keloidal blastomycosis and named it Jorge Lobo's disease. This case was perplexing initially as this fungal infection is very uncommon in the USA. However, with the ever-increasing frequency of international travel, many more cases of lobomycosis have been diagnosed in areas of nonendemicity, such as the USA, Europe, and South Africa. The clinical histories of such imported fungal infections often illustrate their long latency periods. In lobomycosis, the onset of the disease is usually insidious and often difficult to document. We describe a case of a New York resident who presented with multiple skin nodules over both his arms and forearms, and was subsequently diagnosed with Jorge Lobo's disease. The case, diagnosis, histopathologic findings, complication, and management of this rare clinical disease are discussed.

Lobomycosis: A case from Southeastern Europe and review of the literature

Lobomycosis, also known as Jorge Lobo's disease, represents a rare chronic subcutaneous mycosis caused by the fungus Lacazia loboi, an organism that is found within lesions but has not been cultured to date. The natural reservoir of L. loboi is unknown but it is believed to be aquatic, or associated with soil and vegetation. More than 550 human cases have been reported, especially in patients with a history of travel or residence in endemic areas (Central and South America, particularly Brazil) or in communities along rivers. We describe a 64-year-old Greek female farmer living in a coastal region, who presented with an erythematous plaque on her left inner thigh resembling a keloid. The diagnosis was based on the triad: 1) absence of fungal growth in cultures, 2) positive direct microscopic examination of the lesion and 3) histopathology, all consistent with lobomycosis. Particularly, skin biopsy showed deep cutaneous fungal infection with granulomatous reaction. Fungal cells were found inside giant cells. The fungi were thick-walled with some budding, isolated or in short chains. Dermal fibrosis was present. Our patient had a medical history of common variable immunodeficiency but no history of travel to South or Central America. She probably acquired this rare infection by injury during her agricultural works. Our case represents probably the first documented case of human lobomycosis in Southeastern Europe. This case is unusual due to the rarity of lobomycosis in Mediterranean countries, particularly in Southeastern Europe.

Doença de Jorge Lobo de localização labial exclusiva

Jorge Lobo's Disease (JLD) is a chronic granulomatous cutaneous mycosis caused by Lacazia loboi. The most typical lesions are keloid-like growths preferentially located on limbs and ears. To the best of the authors' knowledge, only one labial case has previously been reported. We describe the case of a man who presented with a left-sided papulonodular lesion of 10 years' duration on the vermillion border of the upper lip. A successful surgical resection of the lesion was performed and there was no recurrence in eight years of follow-up.

Detection of cytokines and nitric oxide synthase in skin lesions of Jorge Lobo's disease patients

Studies investigating the immunopathological aspects of Jorge Lobo's disease have shown that the inflammatory infiltrate consists mainly of histiocytes and multinucleated giant cells involving numerous yeast-like cells of Lacazia loboi, with the T lymphocytes more common than B lymphocytes and plasma cells. The quantification of cytokines in peripheral blood mononuclear cells culture supernatant has revealed alterations in the cytokines profile, characterized by predominance of a Th2 profile. In view of these findings and of the role of cytokines in cell interactions, the objective of the present study was to investigate the presence of the cytokines IL-10, TGF-ß1 and TNF-α, as well as iNOS enzyme in granulomas induced by L. loboi. Histological sections obtained from skin lesions of 16 patients were analyzed by immunohistochemistry for the presence of these cytokines and iNOS. The results showed that TGF-ß1 was the cytokine most frequently expressed by cells present in the inflammatory infiltrate, followed by IL-10. There was a minimum to discrete positivity of cells expressing TNF-α and iNOS. The results suggest that the presence of immunosuppressive cytokines in skin lesions of patients with the mycosis might be responsible for the lack of containment of the pathogen as demonstrated by the presence of numerous fungi in the granuloma.

Ten years experience with Jorge Lobo's disease in the state of Acre, Amazon region, Brazil

Jorge Lobo's disease is a cutaneous and subcutaneous mycosis that affects patients in the Amazon region. The number of patients is relatively small, but the real situation of the disease as public health problem is not known, because Jorge Lobo's disease is not a notifiable disease. This study aims to report the clinical evolution in patients affected and to determine the prevalence and areas of occurrence of the disease. A retrospective study was carried out based on the analysis of the clinical records, which included a collection of photographs of patients in the Department of Sanitary Dermatology, in Rio Branco, and patients seen in the interior of the state. In a decade, in Rio Branco, 249 cases of the disease were reported, 30 were females and 219 males. Of these patients, 153 had localized lesions, 94 of them were on one ear, 55 had multifocal lesions and 41 had disseminated lesions. The average time between the onset of symptoms and diagnosis was 19 years. The average age at the time of diagnosis was 53 years, and ages ranged from 14 to 96 years.

Fine-needle aspiration may replace skin biopsy for the collection of material for experimental infection of mice with Mycobacterium leprae and Lacazia loboi

Procedures involving the use of Mycobacterium leprae and Lacazia loboi, uncultivated organisms, depend on the collection of material from the lesions of patients or experimental animals. This study compared fine-needle aspiration (FNA) and skin biopsy methods for obtaining bacilli and fungal cells to experimentally infect animals. Lepromas from one armadillo and one enlarged footpad of a mouse previously inoculated with L. loboi were submitted to FNA and biopsy. Materials collected were processed for inoculation in mice. Acid-fast bacilli (AFB) collected by two FNA procedures yielded 7.2×10(7) and 5.3×10(6) AFB/ml and biopsies yielded 1.58×10(8) and 3.5×10(8) AFB/ml from each leproma. Yeast-like cells of L. loboi collected by FNA yielded 1.0×10(6) fungal cells/ml and biopsy 1.0×10(7) fungal cells/ml. After 8 months, inoculated animals were sacrificed and the inoculated footpads submitted to histopathological examination and counting of AFB and fungal cells. The results obtained by the two methods were comparable for both microorganisms. Biopsy may be replaced by FNA during harvesting of material for different purposes, especially for experimental inoculation of mice in leprosy and Jorge Lobo's disease, with the advantage of FNA being a simpler, less invasive, and less costly method.