Sporotrichosis

Key Features

• Subacute cutaneous ulcers

• New lesions appearing proximal to existing lesions along a draining lymphatic

• Absence of systemic symptoms

• Isolation of Sporothrix schenckii from wound drainage or biopsy

Clinical Findings

• Cutaneous disease is by far the most common manifestation

• Typically an initial papular lesion slowly becomes nodular and ulcerates

• Subsequent new lesions develop in a similar fashion proximally along lymphatics draining the primary lesion

• This sequence of developing painless, chronic ulcers in a linear pattern is strongly suggestive of the diagnosis

• Solitary lesions may exist and some lesions may develop a verrucous character

• Systemic symptoms are absent and laboratory evaluations are normal, except for acute-phase reactants

• The fungus rarely disseminates in immunocompetent hosts

• Cavitary pneumonia is an uncommon manifestation when patients inhale the spores

• Disseminated skin lesions and multiorgan disease with extensive pneumonia may develop in immunocompromised patients, especially those with HIV infection

Diagnosis

• Culture

• Biopsy of skin lesions

  • Demonstrates a suppurative response with granulomas

  • Provides the best source for laboratory isolation

  • Occasionally, the characteristic yeast will be seen

Treatment

• Itraconazole

  • Dosage: 200 mg/d or 5 mg/kg/d for 2–4 weeks after lesions heal, usually 3–6 months

  • Pulmonary or osteoarticular disease, especially in immunocompromised individuals, requires longer therapy

• Amphotericin B may be required for disseminated disease, CNS disease, and severe pulmonary disease

• Surgical debridement may be required