Human case of lobomycosis

Multiple Umbilicated Papules on the Face

A man in his 20s presented to the dermatology department with a monthlong history of gradually progressing papules and nodules on the face, accompanied by fever, fatigue, and weight loss. What is your diagnosis?

Lobomycosis in a Post-Covid 19 Patient: A Case Report and Review of Literature

AIM

To document a case of lobomycosis and to discuss its epidemiology & diagnosis.

CASE REPORT

A 53-year-old male presented with a history of nasal congestion, nasal discharge, and epistaxis following Covid 19 infection. On physical examination, there was necrotic slough in the nasal vestibule near the inferior turbinate. Scrapings and punch biopsy were taken from the lesion. Hematoxylin-eosin-stained sections showed necrotic and mucoid areas with mixed inflammatory cell infiltration and numerous budding yeasts 3- 7μm diameter in singles, and small clusters with single narrow based budding as well as multiple budding including sequential budding forming "chains of yeasts". A diagnosis of Lobomycosis was made. Yeasts of lobomycosis are often confused with other yeasts such as P. brasiliensis, Candida spp., B. dermatitidis, and Cryptococci, but characteristic 'sequential budding' with a 'chain of yeasts" aid in the final diagnosis. Demonstration of yeasts with characteristic chains either in tissue sections or in potassium hydroxide (KOH) preparation of scraped material, exudate, or exfoliative cytology is the mainstay in the diagnosis as the organisms are uncultivable in vitro in culture medium.

Lobomycosis Epidemiology and Management: The Quest for a Cure for the Most Neglected of Neglected Tropical Diseases

Lobomycosis is a chronic disease caused by Lacazia loboi, which is endemic to the Amazon rainforest, where it affects forest dwellers in Brazil. There is no disease control program and no official therapeutic protocol. This situation contributes to an unknown disease prevalence and unmet needs of people disabled by this disease who seek access to treatment. This review provides an update on the subject with an emphasis on therapeutic advances in humans. All relevant studies that addressed epidemiology, diagnosis, or therapeutics of lobomycosis were considered. Seventy-one articles published between 1931 and 2021 were included for a narrative literature review on the epidemiology and quest for a cure. An effective therapy for lobomycosis has been found following decades of research led by the State Dermatology Program of Acre in the Amazon rainforest, where the largest number of cases occur. This discovery opened new avenues for future studies. The main recommendations here, addressed to the Brazilian Ministry of Health, are for lobomycosis to become a reportable disease to ensure that disease prevalence is measured, and that it be prioritized such that affected individuals may access treatment free-of-charge.

The taxonomy of two uncultivated fungal mammalian pathogens is revealed through phylogeny and population genetic analyses

Ever since the uncultivated South American fungal pathogen Lacazia loboi was first described 90 years ago, its etiology and evolutionary traits have been at the center of endless controversies. This pathogen infects the skin of humans and as long believed, dolphin skin. However, recent DNA analyses of infected dolphins placed its DNA sequences within Paracoccidioides species. This came as a surprise and suggested the human and dolphin pathogens may be different species. In this study, population genetic analyses of DNA from four infected dolphins grouped this pathogen in a monophyletic cluster sister to P. americana and to the other Paracoccidioides species. Based on the results we have emended the taxonomy of the dolphin pathogen as Paracoccidioides cetii and P. loboi the one infecting human. Our data warn that phylogenetic analysis of available taxa without the inclusion of unusual members may provide incomplete information for the accurate classification of anomalous species.

Epidemiologic and Clinical Progression of Lobomycosis among Kaiabi Indians, Brazil, 1965-2019

Lobomycosis is a rare granulomatous skin disease with a high prevalence in the Amazon region. The Kaiabi Indians are an especially affected group. We studied the current epidemiologic and clinical progression of lobomycosis among the Kaiabi in Brazil, from initial case reports in 1965 through 2019. A total of 60 lobomycosis cases had been reported among the Kaiabi, and we identified 3 new cases in our review. Of 550 cases of lobomycosis ever reported worldwide, 11.5% were among the Kaiabi. We note a high incidence among female Kaiabi and a precocious onset of disease in this indigenous population. Male Kaiabi frequently are infected with the multicentric form and women more frequently exhibit the localized form. Ulcerated lesions are observed more often in the multicentric form. The prevalence among this indigenous group could be explained by genetic susceptibility and lifestyle, which exposes them to a particular agent in the habitats in which they live.

What is your diagnosis? Keloidal cord-like lesion on the leg

We report a 74-year-old male presented to an outpatient dermatology clinic in Manaus, Amazonas, with a one-year history of pruritic, keloidal lesions on his left lower extremity. Histopathology showed round structures in reticular dermis. Grocott methenamine silver stain revealed numerous round yeasts with thick double walls, occurring singly or in chains connected by tubular projections. The diagnosis was lobomycosis. Although the keloidal lesions presented by this patient are typical of lobomycosis, their linear distribution along the left lower limb is unusual.

Lobomycosis in Soldiers, Colombia

Lobomycosis is a disease that is endemic to the Amazon rainforest and is caused by the still uncultured fungus Lacazia loboi. This disease occurs in loggers, farmers, miners, fishermen, and persons living near coastal rivers of this region. We report 6 soldiers in Colombia in whom lobomycosis developed after military service in the Amazon area. The patients had nodular and keloid-like lesions on the face, neck, trunk, and limbs. The duration of illness ranged from 2 years to 15 years. The initial diagnosis was leishmaniasis on the basis of clinical manifestations and direct smear results, but biopsies confirmed the final diagnosis of lobomycosis. Treatment with surgical excision, itraconazole and clofazimine was satisfactory. However, the follow-up time was short. Healthcare professionals responsible for the diagnosis and treatment of skin diseases need to be able to recognize the clinical signs of lobomycosis and differentiate them from those of cutaneous leishmaniasis.

Case Report: Molecular Confirmation of Lobomycosis in an Italian Traveler Acquired in the Amazon Region of Venezuela

Lobomycosis is a chronic skin mycosis endemic in Amazon regions characterized by chronic nodular or keloidal lesions caused by Lacazia loboi, an uncultivable fungus. Imported cases in nonendemic countries are rare and diagnosed after years. We describe a case of lobomycosis in a healthy 55-year-old Italian traveler who had acquired the infection during 5-day-honeymoon in the Amazon region of Venezuela in 1999. Several weeks after return, he recalled pruritus and papular skin lesions on the left lower limb, subsequently evolving to a plaque-like lesion. Blastomycosis and cryptococcosis were hypothesized based on microscopic morphology of yeast-like bodies found in three consecutive biopsies, although fungal cultures were always negative. In 2016, exfoliative cytology and a biopsy specimen examination showed round yeast-like organisms (6-12 μm), isolated or in a chain, connected by short tubular projections fulfilling the morphologic diagnostic criteria of Lacazia spp. The microscopic diagnosis was confirmed by molecular identification.

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: epidemiology, clinical presentation, and management options

Lobomycosis is a subcutaneous mycosis of chronic evolution caused by the Lacazia loboi fungus. Its distribution is almost exclusive in the Americas, and it has a particularly high prevalence in the Amazon basin. Cases of lobomycosis have been reported only in dolphins and humans. Its prevalence is higher among men who are active in the forest, such as rubber tappers, bushmen, miners, and Indian men. It is recognized that the traumatic implantation of the fungus on the skin is the route by which humans acquire this infection. The lesions affect mainly exposed areas such as the auricles and upper and lower limbs and are typically presented as keloid-like lesions. Currently, surgical removal is the therapeutic procedure of choice in initial cases. Despite the existing data and studies to date, the active immune mechanisms in this infection and its involvement in the control or development of lacaziosis have not been fully clarified. In recent years, little progress has been made in the appraisal of the epidemiologic aspects of the disease. So far, we have neither a population-based study nor any evaluation directed to the forest workers.

Lobomycosis: risk of zoonotic transmission from dolphins to humans

Lobomycosis, a fungal disease of the skin and subcutaneous tissues caused by Lacazia loboi, is sometimes referred to as a zoonotic disease because it affects only specific delphinidae and humans; however, the evidence that it can be transferred directly to humans from dolphins is weak. Dolphins have also been postulated to be responsible for an apparent geographic expansion of the disease in humans. Morphological and molecular differences between the human and dolphin organisms, differences in geographic distribution of the diseases between dolphins and humans, the existence of only a single documented case of presumed zoonotic transmission, and anecdotal evidence of lack of transmission to humans following accidental inoculation of tissue from infected dolphins do not support the hypothesis that dolphins infected with L. loboi represent a zoonotic hazard for humans. In addition, the lack of human cases in communities adjacent to coastal estuaries with a high prevalence of lobomycosis in dolphins, such as the Indian River Lagoon in Florida (IRL), suggests that direct or indirect transmission of L. loboi from dolphins to humans occurs rarely, if at all. Nonetheless, attention to personal hygiene and general principals of infection control are always appropriate when handling tissues from an animal with a presumptive diagnosis of a mycotic or fungal disease.

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

BACKGROUND

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.

MAIN OBSERVATIONS

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.

CONCLUSION

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.

Lobomycosis

Lobomycosis is a rare chronic fungal infection of the subcutaneous tissue found in South America, mainly in Brazil. It is caused by Lacazia loboi. Its clinical manifestations are dermal nodules, either lenticular or in plaques, and keloidlike lesions that can resemble nodular leprosy or leishmaniasis, other subcutaneous mycoses (sporotrychosis, chromomycosis, paracoccidioidomycosis), keloids, and malignant tumors. Diagnosis is made by the histopathological findings of the fungus. For treatment, surgical removal of the lesions, followed by itraconazole and clofazimine for disseminated lesions, has been used with variable results.

Molecular diagnosis of lobomycosis-like disease in a bottlenose dolphin in captivity

We report the diagnosis and molecular characterization of lobomycosis-like lesions in a captive bottlenose dolphin. The clinical picture and the absence of growth in conventional media resembled the features associated with Lacazia loboi. However sequencing of ribosomal DNA and further phylogenetic analyses showed a novel sequence more related to Paracoccidioides brasilensis than to L. loboi. Moreover, the morphology of the yeast cells differed from those L. loboi causing infections humans. These facts suggest that the dolphin lobomycosis-like lesions might have been be caused by different a different fungus clustered inside the order Onygenales. A successful treatment protocol based on topic and systemic terbinafine is also detailed.

Lobomycosis. Literature review and future perspectives

Lobomycosis is a cutaneous infection of tropical and subtropical regions caused by the fungus Lacazia loboi, which still has a controversial taxonomical position. The first description of the disease and fungus was made in 1930 by Jorge Lobo. It is a chronic disease with predominance of lesions similar to keloids, in exposed areas, limited to skin and semimucosa. There is no systemic involvement and patients maintain a good general health. Diagnosis is confirmed by direct or histopathologic exam and, until present, the fungus has not been cultivated. Surgery is the treatment of choice for isolated lesions, but there are frequent recurrences. Good therapeutic responses have been reported with clofazimine, with or without itraconazole, and with 5-fluorocytosine. This disease should be recognized by dermatologists worldwide because, although restricted to the Amazon region, it has been observed in other locations. Research development and achievement of new knowledge in molecular biology and genetic engineering of lobomycosis are of utmost importance because they may, in the future, lead to the culture of the fungus in the laboratory and to a better understanding of its pathogenesis, transmission mechanism, and new methods of diagnosis, prevention and treatment.

Lobomycosis: diagnosis and management of relapsed and multifocal lesions

We report a case of lobomycosis in the left leg of a patient that had traveled to the endemic Brazilian Amazon region. After surgical resection of the lesion, there was relapse with local dissemination of the disease and the treatment was successfully performed by oral itraconazole and cryosurgery.

Accidental Jorge Lobo's disease in a worker dealing with Lacazia loboi infected mice: a case report

INTRODUCTION

Jorge Lobo's disease (Lacaziosis) is a subcutaneous infection of humans living in the Amazon region of Latin America, and in dolphins inhabiting the east coastal areas of the United States. The disease mainly affects people from rural areas living or working in close contact with vegetation and aquatic environments. Most patients refer having developed lesions after accidental trauma with plant thorns or insect bites. Inter-human transmission has never been confirmed suggesting that Lacazia loboi is acquired from environmental propagules.

CASE PRESENTATION

We report the case of a 41-year-old woman from São Paulo, Brazil, a non-endemic area of Jorge Lobo's disease, with L. loboi skin infection most likely accidentally acquired while manipulating experimentally infected mice in the laboratory.

CONCLUSION

Because many patients with Jorge Lobo's disease do not recall accidental skin trauma before their infections, the possibility of accidentally acquired Jorge Lobo's disease through unnoticed broken skin should be considered during the clinical investigation of nodular skin diseases in people who have contact with the fungus or who live in endemic areas. This is the second report of animal to human transmission of this disease.

Lobomycosis in bottlenose dolphins (Tursiops truncatus) from the Indian River Lagoon, Florida: estimation of prevalence, temporal trends, and spatial distribution

Lobomycosis (lacaziosis) is a chronic fungal disease of the skin that affects only dolphins and humans. Previous studies have shown a high prevalence of lobomycosis in bottlenose dolphins (Tursiops truncatus) from the Indian River Lagoon, Florida (IRL). We studied the occurrence and distribution of lobomycosis in the IRL using photo-identification survey data collected between 1996 and 2006. Our objectives were to (1) determine the sensitivity and specificity of photo-identification for diagnosis of lobomycosis in free-ranging dolphins; (2) determine the spatial distribution of lobomycosis in the IRL; and (3) assess temporal patterns of occurrence. Photographs from 704 distinctly marked dolphins were reviewed for skin lesions compatible with lobomycosis. The presumptive diagnosis was validated by comparing the results of photographic analysis with physical examination and histologic examination of lesion biopsies in 102 dolphins captured and released during a health assessment and 3 stranded dolphins. Twelve of 16 confirmed cases were identified previously by photography, a sensitivity of 75%. Among 89 dolphins without disease, all 89 were considered negative, a specificity of 100%. The prevalence of lobomycosis estimated from photographic data was 6.8% (48/704). Spatial distribution was determined by dividing the IRL into six segments based on hydrodynamics and geographic features. The prevalence ranged from <1% in the Mosquito Lagoon to 16.9% in the south Indian River. The incidence of the disease did not increase during the study period, indicating that the disease is endemic, rather than emerging. In summary, photo-identification is a useful tool to monitor the course of individual and population health for this enigmatic disease.

Immune dysfunction in Atlantic bottlenose dolphins (Tursiops truncatus) with lobomycosis

Lobomycosis (Lacaziosis) occurs only in humans and dolphins under natural conditions. We evaluated the immune status of eight dolphins with lobomycosis and 40 healthy dolphins from the Indian River Lagoon (IRL), Florida. Lobomycosis cases had multiple abnormalities in their immunologic parameters when compared to healthy dolphins. The absolute number of circulating lymphocytes and serum albumin concentration were reduced (P<0.05) while the segmented neutrophils, alpha 1, total beta, total gamma and total globulins were increased (P<0.05). Although innate immunity was relatively intact and phagocytosis and natural killer cell activity were not affected, the plasma lysozyme concentrations were elevated in dolphins with lobomycosis (P<0.05). Adaptive immunity was depressed with statistically significant decreases found in the absolute numbers of CD4(+) helper T cells and CD19(+) and CD21(+) B cells. The ratios of CD2(+) T cells to CD4(+) cells and CD2(+) to CD21(+) cells were increased (P=0.05 and P<0.05, respectively) and the numbers of lymphocytes expressing MHC class II molecules was decreased in dolphins with lobomycosis (P<0.05). Lymphocyte proliferation was reduced in response to stimulation with lipopolysaccharide and concanavalin A (P<0.05). Antibody titers to Erysipelas rhusiopathiae, a common marine micro-organism, were decreased (P<0.05). In summary, dolphins with lobomycosis exhibit significant impairment in adaptive immunity.

Use of sera from humans and dolphins with lacaziosis and sera from experimentally infected mice for Western Blot analyses of Lacazia loboi antigens

Antibodies in the sera of patients with lacaziosis recognized an approximately 193-kDa antigen and other Lacazia loboi antigens. Paracoccidioides brasiliensis gp43 antigen was detected by all evaluated sera, but they failed to detect a protein with the same molecular mass in L. loboi extracts. This study is the first to examine the humoral response to L. loboi antigens by using multiple host sera.

Lacaziose (doença de Jorge Lobo): revisão e atualização

Lacaziose ou doença de Jorge Lobo é micose crônica, granulomatosa, causada por implantação traumática do fungo Lacazia loboi - patógeno não cultivável até o presente - nos tecidos cutâneo e subcutâneo, manifestando-se clinicamente por lesões nodulares queloidianas predominantes, envolvendo sobretudo pavilhões auriculares, face, membros superiores e inferiores, e não comprometendo as mucosas. A maioria dos casos humanos está registrada em países da América do Sul. Entretanto, a enfermidade apresenta aspectos epidemiológicos destacados, como o aparecimento em tribo Caiabi, no Brasil Central e em mamíferos não humanos, golfinhos de duas espécies (Tursiops truncatus e Sotalia guianensis) capturados na costa da Flórida (EUA), na foz do rio Suriname, na costa de Santa Catarina (Brasil), no golfo de Gasconha (baía de Biscaia-Europa), com manifestações cutâneas e achados histopatológicos muito similares às encontradas no homem. O artigo objetiva abordar características do fungo e sua taxonomia, e aspectos históricos, ecoepidemiológicos, clínicos, imuno-histoquímicos, histopatológicos, ultra-estruturais e terapêuticos.

Lobomycosis in Venezuela

Lobomycosis is a chronic dermal infection that presents a wide spectrum of clinical- dermatological manifestations, mainly characterized by the development of keloid lesions as well as nodular, verrucoid and sometimes ulcerous forms. The etiological agent at an international level, according to the consensus nomenclature, has been called Loboa loboi, even though recently it has been accommodated as Lacazia loboi. The present review extensively covers the clinical-epidemiological aspects as well as the most outstanding historical aspects, including the Venezuelan experience and the presentation of two new cases, which substantiate the Amazon basin as an endemic area for the disease.

Lobomycosis in Atlantic bottlenose dolphins from the Indian River Lagoon, Florida

OBJECTIVE

To determine the prevalence of lobomycosis, a mycotic infection of dolphins and humans caused by a yeastlike organism (Lacazia loboi), among dolphins in the Indian River Lagoon in Florida.

DESIGN

Cross-sectional study.

ANIMALS

146 Atlantic bottlenose dolphins.

PROCEDURE

Comprehensive health assessments of bottlenose dolphins in the Indian River Lagoon of Florida (n = 75) and in estuarine waters near Charleston, SC (71), were conducted during 2003 and 2004. Bottlenose dolphins were captured, examined, and released. Skin lesions were photographed and then biopsied. Tissue sections were stained with H&E and Gomori methenamine silver stains for identification of L. loboi.

RESULTS

9 of 30 (30%) dolphins captured in the southern portion of the Indian River Lagoon had lobomycosis, whereas none of the 45 dolphins captured in the northern portion of the lagoon or of the 71 dolphins captured near Charleston, SC, did. Affected dolphins had low serum alkaline phosphatase activities and high acute-phase protein concentrations.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggest that lobomycosis may be occurring in epidemic proportions among dolphins in the Indian River Lagoon. Localization of the disease to the southern portion of the lagoon, an area characterized by freshwater intrusion and lower salinity, suggests that exposure to environmental stressors may be contributing to the high prevalence of the disease, but specific factors are unknown. Because only dolphins and humans are naturally susceptible to infection, dolphins may represent a sentinel species for an emerging infectious disease.

Molecular model for studying the uncultivated fungal pathogen Lacazia loboi

Lacazia loboi is an uncultivated fungal pathogen of humans and dolphins that causes cutaneous and subcutaneous infections only in the tropical areas of the Americas. It was recently found by phylogenetic analysis that this unusual pathogen is closely related to Paracoccidioides brasiliensis and to the other fungal dimorphic members of the order Onygenales. That original phylogenetic study used universal primers to amplify well-known genes. However, this approach cannot be applied to the study of other proteins. We have developed a strategy for studying the gene encoding the gp43 homologous protein of P. brasiliensis in L. loboi. The gp43 protein was selected because it has been found that this P. brasiliensis antigen strongly reacts when it is used to test sera from patients with lacaziosis. The principle behind this idea was to obtain the gp43 amino acid sequence of P. brasiliensis and other homologous fungal sequences from GenBank and design primers from their aligned conserved regions. These sets of primers were used to amplify the selected regions with genomic DNA extracted from the yeast-like cells of L. loboi from experimentally infected mice. Using this approach, we amplified 483 bp of the L. loboi gp43-like gene. These sequences had 85% identity at the nucleotide level and 75% identity with the deduced amino acid sequences of the P. brasiliensis gp43 protein. The identity of the 483-bp DNA fragment was confirmed by phylogenetic analysis. This analysis revealed that the L. loboi gp43-like deduced amino acid sequence formed a strongly supported (100%) sister group with several P. brasiliensis gp43 sequences and that this taxon in turn was linked to the other fungal sequences used in this analysis. This study shows that the use of a molecular model for investigation of the genes encoding important proteins in L. loboi is feasible.