Atypical Clinical Presentation of Sporotrichosis Caused by Sporothrix globosa Resistant to Itraconazole

Abstract

Abstract. Sporotrichosis is a polymorphic disease of humans and animals, which is acquired via traumatic inoculation of Sporothrix propagules into cutaneous or subcutaneous tissue. The etiological agents are in a clinical complex, which includes Sporothrix brasiliensis, Sporothrix schenckii, Sporothrix globosa, and Sporothrix luriei, each of which has specific epidemiological and virulence characteristics. Classical manifestation in humans includes a fixed localized lesion at the site of trauma plus lymphocutaneous sporotrichosis with fungal spreading along the lymphatic channels. Atypical sporotrichosis is a challenge to diagnosis because it can mimic many other dermatological diseases. We report an unusual, itraconazoleresistant cutaneous lesion of sporotrichosis in a 66-year-old Brazilian man. Histopathological examination of the skin revealed vascular and fibroblastic proliferation with chronic granulomatous infiltrate composed of multinucleated giant cells. Sporothrix were isolated from the skin lesion, and phylogenetic analyses confirmed it to be sporotrichosis due to S. globosa, a widespread pathogen. Immunoblotting analysis showed several IgG-reactive molecules in autochthonous preparations of the whole cellular proteins (160, 80, 60, 55, 46, 38,35, and 30 kDa) and exoantigen (35 and 33 kDa). The patient was first unsuccessfully treated with daily itraconazole, and then successfully treated with potassium iodide.

Exploring virulence and immunogenicity in the emerging pathogen Sporothrix brasiliensis

“…To assess the humoral response against Sporothrix species, mice have been widely used in experimental sporotrichosis, as well as serum derived from naturally infected humans [ 59 , 60 ] and cats [ 33 , 34 ]. Cellular and humoral immune responses triggered upon Sporothrix introduction into the subcutaneous tissue may play important roles in the development and severity of sporotrichosis [ 61 – 63 ].…”

Immunopathogenesis of Human Sporotrichosis: What We Already Know

“…In Venezuela, S. schenckii and S. globosa are the most common species that have been isolated from human lesions, and S. globosa has been associated with fixed lesions which represent the less severe clinical form [ 89 ]. However, Fischman Gompertz et al evidenced atypical clinical manifestation due to S. globosa infection and resistance to treatment with itraconazole [ 90 ]. Regarding virulence factors, Hernández-Chaves et al pointed out that the cell wall is a dynamic organelle vital to different functions such as cell viability, morphogenesis, and pathogenesis and has an impressive capability to adapt its composition and organization under environmental pressure.…”

Fixed cutaneous sporotrichosis

“…Sporotrichosis is dispersed worldwide and more prevalent in tropical and subtropical areas, with the highest prevalence in Central and South America, Africa and Japan [1,3,4]. Sporotrichosis is caused by a complex group of dimorphic fungus species called Sporothrix [1,[5][6][7], the major species includes Sporothrix brasiliensis, S. schenckii, S. globosa and S. albicans and S. mexicana [8][9][10][11]. Sporothrix is present on the natural environment in soil, dead wood (Splinter and thorns favor the growth), mosses and cornstalks [12].…”

“…Differential diagnoses include cutaneous chronic infections such as cutaneous leshmaniasis in its localized form, but the typical ulcer is painless with erythematous base and well defined high edges [6]. It must be differentiated from tuberculosis, sarcoidosis, paracoccidioidomycosis, chromoblastomycosis, leprosy and other mycobacterial diseases [2,9]. Clinical suspicion is essential for diagnosis.…”