Sporotrichosis

Sporotrichosis is an ulcerated, reddened nodule at the site of a puncture wound that may evolve into chronic nodular lymphangitis without treatment. Regional lymph nodes are not usually involved. It is a fungal disease of the skin and lymphatics that follows a puncture wound contaminated with soil.

CASES/YEAR
60,000 (US); 1,200,000 (Global)
CATEGORY
Sapronoses
AGENT TYPE
Fungi (Endemic-Dimorphic)
OTHER NAMES
Sporothrix schenkii infection;
ACUITY
Subacute/Chronic
INCUBATION
1 week to 3 months; [CCDM]
INITIAL SYMPTOMS
Ulcerated, reddened nodule at the site of a puncture wound that may evolve into chronic nodular lymphangitis without treatment; [Merck Manual, p. 1576-7] Regional lymph nodes are not usually involved. {Cohen, 3rd Ed, p. 1865]
PRECAUTIONS
"Person-to-person transmission has only rarely been documented." [CCDM, p. 570]
COMMENTS
FINDINGS:
Sporotrichosis usually follows puncture wounds of the extremities. It is characterized by a growing nodule at the wound site and the development of firm cords in the draining lymphatics. Nodules may ulcerate. Complications are rare except in patients with AIDS or other chronic diseases and include arthritis, osteomyelitis, and pulmonary infections. [CCDM, p. 569] The two types of cutaneous sporotrichosis are the lymphocutaneous form and the fixed cutaneous or plaque form that does not spread by the lymph vessels. In patients with underlying COPD, S. schenkii can cause cavitary lung disease similar to tuberculosis or histoplasmosis. The fungus can also cause chronic infections of bones and joints. Widespread infections are seen in some AIDS patients with CD4+ lymphocyte counts less than 200 cells/mL. [ID, p. 2246-7] Infections may remain localized or spread proximally to involve the regional lymph nodes. Pulmonary sporotrichosis may occur, usually in older patients. From the lungs, the disease can spread to the skin, eyes, and brain. Eye diseases include keratoconjunctivitis, Parinaud's oculoglandular syndrome, and uveitis. [Guerrant, p. 606, 1004-5] Initial skin lesions are red and papulonodular from a few mm to a few cm in size. They may be smooth or verrucous and may ulcerate or develop raised red borders. The most common sites for extracutaneous sporotrichosis are the bones and joints. Immunocompetent patients usually have involvement at only one site and do not have systemic symptoms. Patients with extracutaneous infections often present without a history of previous skin involvement. Common sites are the elbow, ankle, and knee, but not the hip, shoulder, or spine. Leukocytosis and mild anemia may be present. [PPID, p. 3131-3] Pulmonary sporotrichosis is rare; findings include productive cough, fever, weight loss, hemoptysis, and enlargement of perihilar lymph nodes. [CID 2007;45:1255-65] Fever and headache are symptoms in the rare cases of CNS infection. [Wallach, p. 1170]

EPIDEMIOLOGY:
Sporotrichosis is mainly a disease of the skin and lymphatics that follows a puncture wound contaminated with soil. Uncommon manifestations are osteoarticular (middle-aged alcoholics), pulmonary (COPD sufferers), and disseminated (AIDS patients). [Harrison ID, p. 1025] Patients with alcoholism, diabetes, and COPD are at risk for osteoarticular and pulmonary infections. [Cecil, p. 2044] Zoonotic transmission has been described from cat bites and scratches or from handling infected cats and horses with skin lesions. [ID, p. 1424, 2246-7] Scratches from digging animals such as armadillos may transmit infection. [CID 2007;45:1255-65] Also case reports of transmission by squirrels, horses, dogs, cats, pigs, insects, and birds; [PPID, p. 3131] Endophthalmitis (blindness) is very rare. [Cohen, 3rd Ed, p. 1865]
DIAGNOSTIC
Culture: Grows out in a few days; Fungal stains of biopsy specimens: Organism not usually found in histopathological preparations; Serology not standardized; PCR available at reference labs; [Cecil, p. 2045]
SCOPE
Global
SIGNS & SYMPTOMS
  • >fatigue, weakness
  • >fever
  • H anemia
  • H leukocytosis
  • H lymphadenopathy
  • N headache
  • O conjunctivitis, acute
  • O oculoglandular syndrome
  • R cough
  • R dyspnea
  • R hemoptysis
  • R sputum production
  • S entry wound with lymph nodes
  • S lymphangitis
  • S nodular lymphangitis
  • S papules or plaques
  • S pustule
  • S skin or subcutaneous nodule
  • S ulcer of skin
  • S warty growth of the skin
  • X cystic or cavitary lesions
  • X hilar lymphadenopathy
  • X lung infiltrates
  • X pleural effusions
  • *arthritis
  • *brain abscess or lesion
  • *erythema nodosum
  • *meningitis
  • *osteomyelitis
  • *pneumonia
  • *pneumonitis
  • *uveitis
  • *weight loss
ANTIMICROBIC

Yes

VACCINE

No

ENTRY
Skin or Mucous Membranes (Includes Conjunctiva), Animal Bite
SOURCE
Soil or Dust (Ingesting or Inhaling)
RESERVOIR
Birds and Poultry, Cats, Dogs, Horses, Swine, Wild Animals
RISK FACTORS
  • AIDS patients
  • Touch plants containing thorns, splinters, or spaghum moss
DRUG LINK
Merck Manual: Sporotrichosis
REFERENCES FOR CASES/YEAR
1. (US) Using rate from study in New South Wales, 2/100,000, then 2 X 3000 = 6000; Use correction factor of 10 for reported diseases.
2. (Global) Sporadic and uncommon; An occupational disease of farmers and gardeners; About 3000 workers were infected in an epidemic in gold miners in South Africa when the fungus was growing on mine timbers; [CCDM, p. 570] "Delayed hypersensitivity skin testing and antibody assays for S. schenckii have been reported positive in 11% to 26% of individuals tested." [ID, p. 2246] An analysis in New South Wales mid-north coast from 200-2010 found 31 cases with an incidence of 2/100,000; [Sivagnanam2012: PMID 22621152] Estimate: Use US cases/yr X 20;