Human Lobomycosis Caused by Paracoccidioides (Lacazia) loboi, Panama, 2022

We report a patient from Panama who had lobomycosis caused by Paracoccidioides (Lacazia) loboi. We used combined clinical-epidemiologic and phylogenetic data, including a new gene sequence dataset on this fungus in Panama, for analysis. Findings contribute useful insights to limited knowledge of this fungal infection in the Mesoamerican Biologic Corridor.

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 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.

Lobomycosis: a therapeutic challenge

Lobomycosis or lacaziosis is a chronic granulomatous fungal infection caused by Lacazia loboi. Most cases are restricted to tropical regions. Transmission is believed to occur through traumatic inoculation in the skin, mainly in exposed areas. It is characterized by keloid-like nodules. There are only a few hundred cases reported. The differential diagnoses include many skin conditions, and treatment is difficult. The reported case, initially diagnosed as keloid, proved to be refractory to surgical treatment alone. It was subsequently approached with extensive surgery, cryotherapy every three months and a combination of itraconazole and clofazimine for two years. No signs of clinical and histopathological activity were detected during follow-up.

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.

Leprosy and Lobomycosis: First report from the Amazon Region

Leprosy is still a relevant health problem in Brazil with 31 044 new cases diagnosed in 2013, of which 781 new cases diagnosed in the State of Amazonas. Lobomycosis is a cutaneous-subcutaneous mycosis caused by Lacazia loboi, an in vitro uncultivable fungus. Lobomycosis has been mainly reported in the Amazon region of Brazil and Colombia affecting mainly male farmers and workers in extraction of rubber. Lobomycosis is clinically characterised by keloid-like lesions and chronic evolution. Even if lobomycosis does not represent a major public health problem, it remains a serious condition for patients due to unsatisfactory treatment. We report a case of an old man with lepromatous leprosy diagnosed in 1983, treated with multidrug therapy until 1989 and presenting a leprosy relapse 15 years after treatment. At this time a lobomycosis was also diagnosed in a keloid-like lesion evolving for more than 30 years. This co-infection has been only rarely reported and this is the first detailed case report in the English literature.

Advances in tropical diseases

There are six diseases that WHO considers as the major threat in developing countries, leprosy, filariasis, malaria, schistosomiasis, Chagas disease and leishmaniasis; and of these only malaria does not present skin lesions. These diseases are among the so called tropical diseases found in countries of tropical climate, usually infections and infestations considered exotic and rare in European and North American countries. It is extremely important for doctors of all countries to be able to provide correct pre travel counseling and to make early diagnosis and treatment, thus avoiding dissemination of these dieases to non endemic areas. The authors review some important tropical diseases seen in Brazil, as paracoccidiodomycosis, lobomycosis, myiasis, tungiasis, and cutaneous schistosomiasis and discuss new information about them.