Epidemic Cat-Transmitted Sporotrichosis
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《新英格兰医药杂志》
To the Editor: Sporotrichosis is a fungal infection that occurs through traumatic inoculation of organic matter that is contaminated with Sporothrix schenckii and is usually limited to the skin and subcutaneous tissue. In North America, the infection is most commonly associated with scratches from thorn bushes. Occasionally, sporotrichosis has been associated with scratches or bites by animals, especially domestic cats. Little is known about canine and feline transmission of sporotrichosis.
The Evandro Chagas Clinical Research Institute is a referral center for infectious diseases in Rio de Janeiro. Since 1998, the institute has received an increasing number of cases of sporotrichosis in humans, dogs, and cats from the city of Rio de Janeiro and the surrounding areas.1 Between 1986 and 1997, 13 cases of sporotrichosis in humans were recorded at the institute. Beginning in 1998, the number of cases increased steadily,2 reaching a total of 759 cases in humans between 1998 and 2004, 83 percent of whom reported contact with cats that had sporotrichosis as a risk factor. Of these, 56 percent reported cat bites or scratches.
The lymphocutaneous clinical form of sporotrichosis was the most frequent, but rare presentations were also observed, including widespread cutaneous lesions and primary lesions of the conjunctiva and nasal mucosa. Associations with erythema nodosum and erythema multiforme were seen as well.2 There were good responses to treatment with oral itraconazole at a dose of 100 mg per day, with rare adverse effects. Patients infected with the human immunodeficiency virus either had systemic sporotrichosis or cutaneous sporotrichosis or did not become ill after exposure to cats with sporotrichosis.
During the same period, 64 dogs and 1503 cats with sporotrichosis were treated at our institute. Canine sporotrichosis presents mainly as a self-limited mycosis with a favorable therapeutic outcome.3 As with the humans affected in this epidemic, 85 percent of the dogs had a history of contact with cats that had confirmed sporotrichosis. Feline sporotrichosis has a broad spectrum, ranging from subclinical infection to severe systemic disease with hematogenous dissemination of S. schenckii. Sporotrichosis in cats always preceded its occurrence in both their owners and their owner's dogs. The zoonotic potential of infected cats was demonstrated by the isolation of S. schenckii from a feline skin lesion and claw fragments and material collected from the cats' nasal and oral cavities.4
Thus far, it is not known why sporotrichosis emerged as a zoonosis in Rio de Janeiro or why it reached epidemic proportions. We alert physicians in different specialties and veterinarians working outside the epidemic area to the possibility of seeing travelers with classic or even atypical manifestations of sporotrichosis and to the diagnostic challenges involved.
Armando O. Schubach, M.D., Ph.D.
Tania M.P. Schubach, V.M.D., Ph.D.
M?nica B.L. Barros, M.D., Ph.D.
Oswaldo Cruz Foundation
CEP 21040-900 Rio de Janeiro, Brazil
armando@ipec.fiocruz.br
References
de Lima Barros MB, Schubach TM, Galhardo MC, et al. Sporo-trichosis: an emergent zoonosis in Rio de Janeiro. Mem Inst Oswaldo Cruz 2001;96:777-779.
Barros MBL, Schubach Ade O, do Valle AC, et al. Cat-transmitted sporotrichosis epidemic in Rio de Janeiro, Brazil: description of a series of cases. Clin Infect Dis 2004;38:529-535.
Schubach TMP, Schubach A, Okamoto T, et al. Canine sporotrichosis in Rio de Janeiro, Brazil: clinical presentation, laboratory diagnosis and therapeutic response in 44 cases (1998-2003). Med Mycol (in press).
Schubach TM, Schubach A, Okamoto T, et al. Evaluation of an epidemic of sporotrichosis in cats: 347 cases (1998-2001). J Am Vet Med Assoc 2004;224:1623-1629.
The Evandro Chagas Clinical Research Institute is a referral center for infectious diseases in Rio de Janeiro. Since 1998, the institute has received an increasing number of cases of sporotrichosis in humans, dogs, and cats from the city of Rio de Janeiro and the surrounding areas.1 Between 1986 and 1997, 13 cases of sporotrichosis in humans were recorded at the institute. Beginning in 1998, the number of cases increased steadily,2 reaching a total of 759 cases in humans between 1998 and 2004, 83 percent of whom reported contact with cats that had sporotrichosis as a risk factor. Of these, 56 percent reported cat bites or scratches.
The lymphocutaneous clinical form of sporotrichosis was the most frequent, but rare presentations were also observed, including widespread cutaneous lesions and primary lesions of the conjunctiva and nasal mucosa. Associations with erythema nodosum and erythema multiforme were seen as well.2 There were good responses to treatment with oral itraconazole at a dose of 100 mg per day, with rare adverse effects. Patients infected with the human immunodeficiency virus either had systemic sporotrichosis or cutaneous sporotrichosis or did not become ill after exposure to cats with sporotrichosis.
During the same period, 64 dogs and 1503 cats with sporotrichosis were treated at our institute. Canine sporotrichosis presents mainly as a self-limited mycosis with a favorable therapeutic outcome.3 As with the humans affected in this epidemic, 85 percent of the dogs had a history of contact with cats that had confirmed sporotrichosis. Feline sporotrichosis has a broad spectrum, ranging from subclinical infection to severe systemic disease with hematogenous dissemination of S. schenckii. Sporotrichosis in cats always preceded its occurrence in both their owners and their owner's dogs. The zoonotic potential of infected cats was demonstrated by the isolation of S. schenckii from a feline skin lesion and claw fragments and material collected from the cats' nasal and oral cavities.4
Thus far, it is not known why sporotrichosis emerged as a zoonosis in Rio de Janeiro or why it reached epidemic proportions. We alert physicians in different specialties and veterinarians working outside the epidemic area to the possibility of seeing travelers with classic or even atypical manifestations of sporotrichosis and to the diagnostic challenges involved.
Armando O. Schubach, M.D., Ph.D.
Tania M.P. Schubach, V.M.D., Ph.D.
M?nica B.L. Barros, M.D., Ph.D.
Oswaldo Cruz Foundation
CEP 21040-900 Rio de Janeiro, Brazil
armando@ipec.fiocruz.br
References
de Lima Barros MB, Schubach TM, Galhardo MC, et al. Sporo-trichosis: an emergent zoonosis in Rio de Janeiro. Mem Inst Oswaldo Cruz 2001;96:777-779.
Barros MBL, Schubach Ade O, do Valle AC, et al. Cat-transmitted sporotrichosis epidemic in Rio de Janeiro, Brazil: description of a series of cases. Clin Infect Dis 2004;38:529-535.
Schubach TMP, Schubach A, Okamoto T, et al. Canine sporotrichosis in Rio de Janeiro, Brazil: clinical presentation, laboratory diagnosis and therapeutic response in 44 cases (1998-2003). Med Mycol (in press).
Schubach TM, Schubach A, Okamoto T, et al. Evaluation of an epidemic of sporotrichosis in cats: 347 cases (1998-2001). J Am Vet Med Assoc 2004;224:1623-1629.