Case Report: Sweet Syndrome in Patients with Sporotrichosis: A 10-Case Series

Abstract

Human sporotrichosis is an emerging disease caused by fungi of the genus Sporothrix, distributed worldwide, but mostly in tropical and subtropical regions. This disease is caused by traumatic inoculation of contaminated material (either animal or vegetal in origin) into the skin. Sporotrichosis cases caused by zoonotic transmission through felines have significantly increased over the last 20 years in Brazil. There is a spectrum of clinical outcomes, from classical lymphocutaneous and fixed forms to disseminated manifestations and extracutaneous lesions; however, hypersensitivity reactions related to sporotrichosis, including Sweet syndrome (acute febrile neutrophilic dermatoses), are uncommon. In Brazil, Sporothrix brasiliensis is repeatedly associated with feline infection and has consistently shown higher virulence, tendency to escalate to outbreaks or epidemics, and development of atypical forms. Therefore, the objective of the present study was to report the cases of 10 patients with sporotrichosis infected by S. brasiliensis species who developed Sweet syndrome to alert this association, especially in endemic areas.

Hypersensitivity reactions in sporotrichosis: a retrospective cohort of 325 patients from a reference hospital in Rio de Janeiro, Brazil (2005–2018)

“…Our centre, with the largest world sample of sporotrichosis, has allowed us to follow‐up a large number of cases of CHRs. Sporotrichosis cases associated with CHRs follow a sociodemographic and epidemiological pattern similar to the general cases of zoonotic transmission of sporotrichosis in Rio de Janeiro, except for a higher predominance in female patients and when compared with sporotrichosis without CHR, a notable proportion of the fixed cutaneous form has been reported 5 . It is possible that the inflammation of the CHR induces a more localized manifestation of the mycosis, although our results showed no faster healing.…”

“…Lymphocutaneous, fixed cutaneous, disseminated cutaneous and extracutaneous/disseminated forms have been observed 1 . Sporotrichosis‐associated cutaneous hypersensitivity reactions (CHRs), such as erythema nodosum (EN), erythema multiforme (EM) and Sweet syndrome (SS), have been reported only in zoonotic transmission of the disease 2–5 . Hypersensitivity lesions are sometimes mistaken for sporotrichosis lesions, which can compromise appropriate treatment 1,6 .…”

Sporotrichosis: hyperendemic by zoonotic transmission, with atypical presentations, hypersensitivity reactions and greater severity

“…All studied cases of Sweet’s syndrome were associated with infection by S. brasiliensis . 43 In another case series published in 2011, Sweet’s syndrome was more frequent in adult female patients, who were successfully treated with steroids and itraconazole. 44 …”

“…In the zoonotic hyperendemic in Rio de Janeiro that has occurred since the 1990s, in which contact with infected felines is the main source of transmission, patients who are infected with S. brasiliensis have a higher number of statistically significant hypersensitivity reactions and disease dissemination. 4 , 42 , 43 , 44 , 45 , 46 , 47 …”

“…The most frequent of these reactions, Sweet’s syndrome, has responded very well to corticosteroid therapy. 43 Some authors have reported improvement in the clinical picture only with the correct use of antifungal treatment. Gutierrez-Galhardo et al demonstrated the favorable evolution of erythema nodosum associated with sporotrichosis using the standard treatment for mycosis (itraconazole 100 mg/day).…”