Official reprint from UpToDate®
www.uptodate.com ©2017 UpToDate®

Basic biology and epidemiology of sporotrichosis

Carol A Kauffman, MD
Section Editor
Kieren A Marr, MD
Deputy Editor
Jennifer Mitty, MD, MPH


Sporotrichosis is a subacute to chronic infection caused by the dimorphic fungus Sporothrix schenckii. Infection usually involves cutaneous and subcutaneous tissues but can occasionally occur in other sites, primarily in immunocompromised patients. Activities associated with the development of sporotrichosis include landscaping, rose gardening, and other activities that involve inoculation of soil through the skin.

The basic biology of S. schenckii and the epidemiology of sporotrichosis will be reviewed here. The clinical features, diagnosis, and treatment of this infection are discussed separately. (See "Clinical features and diagnosis of sporotrichosis" and "Treatment of sporotrichosis".)


S. schenckii is the primary pathogen in the genus Sporothrix, and most laboratories still identify isolates as S. schenckii. However, molecular studies have found that this species is actually made up of a complex of at least six phylogenetically different species that cluster in different geographic regions [1-5]. S. schenckii sensu stricto occurs worldwide and remains the most common human pathogen, but Sporothrix brasiliensis appears to be equally virulent and causes most infections in Brazil, including the large zoonotic outbreak related to cats in Rio de Janeiro [3]. Sporothrix globosa is found worldwide but causes fewer infections than S. schenckii and S. brasiliensis [4]. Sporothrix mexicana, present in Mexico and other Latin American countries, Sporothrix luriei, and Sporothrix albicans are uncommon causes of infection in humans [5].

Dimorphism — S. schenckii exhibits thermal dimorphism. It produces hyphae in the environment at temperatures that are lower than normal human body temperatures (picture 1) and exists as a yeast form at 37ºC in vitro and in human tissues. Some strains are less thermotolerant than others, growing poorly at temperatures above 35ºC; these strains tend to be found in fixed dermal lesions and do not have the propensity to spread along lymphatics into subcutaneous tissues as do most strains of S. schenckii [6].

Growth in vitro — At 25 to 27ºC, the filamentous form of S. schenckii grows readily on standard media, such as Sabouraud agar. Within one to two weeks, growth begins as a white- to cream-colored mold and then assumes a brown, gray, or black color with further incubation (picture 2). With age, the colonies become wrinkled and, with repeated subculturing, may lose their dark color and turn off-white. The conidia may be dark colored or hyaline and arrange themselves along the hyphae in "bouquet-like" arrangements. The hyphae are thin, septate, and branched.


Subscribers log in here

To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information or to purchase a personal subscription, click below on the option that best describes you:
Literature review current through: Mar 2017. | This topic last updated: Jul 06, 2015.
The content on the UpToDate website is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. The use of this website is governed by the UpToDate Terms of Use ©2017 UpToDate, Inc.
  1. Marimon R, Gené J, Cano J, et al. Molecular phylogeny of Sporothrix schenckii. J Clin Microbiol 2006; 44:3251.
  2. Marimon R, Cano J, Gené J, et al. Sporothrix brasiliensis, S. globosa, and S. mexicana, three new Sporothrix species of clinical interest. J Clin Microbiol 2007; 45:3198.
  3. Galhardo MC, De Oliveira RM, Valle AC, et al. Molecular epidemiology and antifungal susceptibility patterns of Sporothrix schenckii isolates from a cat-transmitted epidemic of sporotrichosis in Rio de Janeiro, Brazil. Med Mycol 2008; 46:141.
  4. Rodrigues AM, de Hoog S, de Camargo ZP. Emergence of pathogenicity in the Sporothrix schenckii complex. Med Mycol 2013; 51:405.
  5. López-Romero E, Reyes-Montes Mdel R, Pérez-Torres A, et al. Sporothrix schenckii complex and sporotrichosis, an emerging health problem. Future Microbiol 2011; 6:85.
  6. Kwon-Chung KJ. Comparison of isolates of Sporothrix schenckii obtained from fixed cutaneous lesions with isolates from other types of lesions. J Infect Dis 1979; 139:424.
  7. Reiss E. Cell wall composition. In: Fungi Pathogenic for Humans and Animals, Part B: Pathogenicity and Detection, Howard DH (Ed), Marcel Dekker, New York 1985. p.57.
  8. Brito MM, Conceição-Silva F, Morgado FN, et al. Comparison of virulence of different Sporothrix schenckii clinical isolates using experimental murine model. Med Mycol 2007; 45:721.
  9. Tsuboi R, Sanada T, Takamori K, Ogawa H. Isolation and properties of extracellular proteinases from Sporothrix schenckii. J Bacteriol 1987; 169:4104.
  10. Dixon DM, Salkin IF, Duncan RA, et al. Isolation and characterization of Sporothrix schenckii from clinical and environmental sources associated with the largest U.S. epidemic of sporotrichosis. J Clin Microbiol 1991; 29:1106.
  11. Dixon DM, Duncan RA, Hurd NJ. Use of a mouse model to evaluate clinical and environmental isolates of Sporothrix spp. from the largest U.S. epidemic of sporotrichosis. J Clin Microbiol 1992; 30:951.
  12. Cunningham KM, Bulmer GS, Rhoades ER. Phagocytosis and intracellular fate of Sporothrix schenckii. J Infect Dis 1979; 140:815.
  13. Rex JH, Bennett JE. Administration of potassium iodide to normal volunteers does not increase killing of Sporothrix schenckii by their neutrophils or monocytes. J Med Vet Mycol 1990; 28:185.
  14. Shiraishi A, Nakagaki K, Arai T. Role of cell-mediated immunity in the resistance to experimental sporotrichosis in mice. Mycopathologia 1992; 120:15.
  15. Tachibana T, Matsuyama T, Mitsuyama M. Involvement of CD4+ T cells and macrophages in acquired protection against infection with Sporothrix schenckii in mice. Med Mycol 1999; 37:397.
  16. Bolao F, Podzamczer D, Ventin M, Gudiol F. Efficacy of acute phase and maintenance therapy with itraconazole in an AIDS patient with sporotrichosis. Eur J Clin Microbiol Infect Dis 1994; 13:609.
  17. Freitas DF, de Siqueira Hoagland B, do Valle AC, et al. Sporotrichosis in HIV-infected patients: report of 21 cases of endemic sporotrichosis in Rio de Janeiro, Brazil. Med Mycol 2012; 50:170.
  18. Bustamante B, Lama JR, Mosquera C, Soto L. Sporotrichosis in human immunodeficiency virus infected Peruvian patients. Infect Dis Clin Pract 2009; 17:78.
  19. Bunce PE, Yang L, Chun S, et al. Disseminated sporotrichosis in a patient with hairy cell leukemia treated with amphotericin B and posaconazole. Med Mycol 2012; 50:197.
  20. Gottlieb GS, Lesser CF, Holmes KK, Wald A. Disseminated sporotrichosis associated with treatment with immunosuppressants and tumor necrosis factor-alpha antagonists. Clin Infect Dis 2003; 37:838.
  21. Pappas PG, Tellez I, Deep AE, et al. Sporotrichosis in Peru: description of an area of hyperendemicity. Clin Infect Dis 2000; 30:65.
  22. Lyon GM, Zurita S, Casquero J, et al. Population-based surveillance and a case-control study of risk factors for endemic lymphocutaneous sporotrichosis in Peru. Clin Infect Dis 2003; 36:34.
  23. Powell KE, Taylor A, Phillips BJ, et al. Cutaneous sporotrichosis in forestry workers. Epidemic due to contaminated Sphagnum moss. JAMA 1978; 240:232.
  24. Hajjeh R, McDonnell S, Reef S, et al. Outbreak of sporotrichosis among tree nursery workers. J Infect Dis 1997; 176:499.
  25. Sanders E. Cutaneous sporotrichosis. Beer, bricks, and bumps. Arch Intern Med 1971; 127:482.
  26. Centers for Disease Control (CDC). Sporotrichosis among hay-mulching workers--Oklahoma, New Mexico. MMWR Morb Mortal Wkly Rep 1984; 33:682.
  27. Dooley DP, Bostic PS, Beckius ML. Spook house sporotrichosis. A point-source outbreak of sporotrichosis associated with hay bale props in a Halloween haunted-house. Arch Intern Med 1997; 157:1885.
  28. Barros MB, 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.
  29. Conti Díaz IA. Epidemiology of sporotrichosis in Latin America. Mycopathologia 1989; 108:113.
  30. Reed KD, Moore FM, Geiger GE, Stemper ME. Zoonotic transmission of sporotrichosis: case report and review. Clin Infect Dis 1993; 16:384.
  31. 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.
  32. Schubach TM, 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 2006; 44:87.
  33. Frean JA, Isaäcson M, Miller GB, et al. Sporotrichosis following a rodent bite. A case report. Mycopathologia 1991; 116:5.
  34. Saravanakumar PS, Eslami P, Zar FA. Lymphocutaneous sporotrichosis associated with a squirrel bite: case report and review. Clin Infect Dis 1996; 23:647.
  35. Haddad VJ, Miot HA, Bartoli LD, et al. Localized lymphatic sporotrichosis after fish-induced injury (Tilapia sp.). Med Mycol 2002; 40:425.
  36. Freitas DF, do Valle AC, de Almeida Paes R, et al. Zoonotic Sporotrichosis in Rio de Janeiro, Brazil: a protracted epidemic yet to be curbed. Clin Infect Dis 2010; 50:453.
  37. Naqvi SH, Becherer P, Gudipati S. Ketoconazole treatment of a family with zoonotic sporotrichosis. Scand J Infect Dis 1993; 25:543.
  38. LURIE HI. Five unusual cases of sporotrichosis from South Africa showing lesions in muscles, bones, and viscera. Br J Surg 1963; 50:585.
  39. Cooper CR, Dixon DM, Salkin IF. Laboratory-acquired sporotrichosis. J Med Vet Mycol 1992; 30:169.