Basics
Description
- Lymphocutaneous:
- Most common form
- Inoculation of fungus (Sporothrix schenckii) into skin/soft tissue
- Disease with or without hematogenous spread after traumatic inoculation with soil or plant material
- Secondary to animal bites/scratches, especially from cats, trauma
- Increased risk: Farmers, gardeners, landscapers, forestry workers
- Pulmonary:
- Inhalation of conidia aerosolized from soil/plant decay
- Increased risk: Alcoholics, diabetics, COPD, steroid users
- Multifocal extracutaneous:
- Cutaneous inoculation and hematologic spread
- Increased risk: HIV/immunosuppressed patients
Etiology
- Fungal infection caused by S. schenckii:
- Dimorphic fungus
- Occurs as mold on decaying vegetation, moss, and soil in temperate and tropical environments
- Animal vectors, notably cats and armadillos
Diagnosis
Signs and Symptoms
- Several clinical manifestations/syndromes
- Determined by mode of inoculation and host factors
- Lymphocutaneous:
- Initial lesions appear days to weeks after inoculation
- Begin as papules, become nodular, often ulcerate:
- Distal extremities more commonly involved
- Size: Millimeters to 4 cm
- Pain absent or mild
- Drainage is nonpurulent
- Systemic symptoms usually absent
- Secondary nodular lesions develop along lymphatics draining the original site.
- May wax and wane over years if untreated
- Fixed cutaneous:
- Plaque-like or verrucous lesion at the site of inoculation (typically face and extremities)
- Ulceration uncommon
- Do not manifest lymphangitic progression
- Common in endemic regions of South America
- Extracutaneous:
- Osteoarticular:
- Secondary to local or hematologic inoculation
- Septic arthritis more common than osteomyelitis
- Joint inflammation, effusion, and pain
- Single or multiple joint involvement of extremities: Knee, elbow, wrist, ankle
- Indolent onset, few systemic symptoms
- Tenosynovitis, septic arthritis, bursitis, nerve entrapment syndrome
- Usually poor outcome due to delayed diagnosis
- Pulmonary:
- Syndrome resembles mycobacterial infection (TB)
- Fever, weight loss, fatigue, night sweats
- Productive cough, hemoptysis, dyspnea
- Uniformly fatal if untreated
- Multifocal extracutaneous (disseminated):
- Low-grade fever, weight loss
- Diffuse cutaneous lesions
- Arthritis/osteolytic lesions/parenchymal involvement
- Chronic lymphocytic meningitis
- Ocular adnexa, endophthalmitis
- Genitourinary, sinuses
- Can be fatal if untreated
- Often occurs in immunocompromised host
History
- Activity with exposure to soil, moss, organic material, or to cats in endemic areas
- Fixed cutaneous or lymphocutaneous: Healthy host
- Disseminated/extracutaneous: Diabetics, COPD, HIV/AIDS
Physical Exam
- Fixed cutaneous/lymphocutaneous: Lesions found on exam
- Disseminated: Nonspecific findings
Essential Workup
Diagnosis dependent on isolation S. schenckii from site of infection:
- Culture from aspirated material, tissue biopsy, or sputum
Diagnosis Tests & Interpretation
Lab
- Blood tests not indicated with cutaneous disease
- Cultures of sputum, synovial fluid, CSF, blood as indicated by extracutaneous manifestations
- No reliable serologic assays available
Imaging
- Pulmonary:
- Chest radiograph reveals cavitary lesions
- Extracutaneous/disseminated:
- Consider bone scan in immunocompromised host.
Diagnostic Procedures/Surgery
- Lymphocutaneous/fixed cutaneous:
- Biopsy reveals pyogranulomatous inflammation, 3 " 5 mm cigar-shaped yeast
- Pulmonary:
- Gram stain of sputum may yield yeast; sputum cultures often positive
- Extracutaneous/disseminated:
- CSF reveals lymphocytic meningitis, increased protein/decreased glucose
Differential Diagnosis
- Lymphocutaneous:
- Leishmaniasis
- Nocardiosis
- Mycobacterium marinum
- Tularemia
- Fixed cutaneous:
- Bacterial pyoderma
- Foreign-body granuloma
- Inflammatory dermatophyte infections
- Blastomycosis
- Mycobacteria
- Osteoarticular:
- Rheumatoid arthritis
- Gout
- Tuberculosis
- Bacterial arthritis
- Pigmented villonodular synovitis
- Pulmonary and meningitis:
- Mycobacterial infections
- Histoplasmosis
- Coccidioidomycosis
- Cryptococcal disease
Treatment
Initial Stabilization/Therapy
Airway/hemodynamic stabilization for severely ill patients with extracutaneous manifestations
Ed Treatment/Procedures
- Lymphocutaneous/fixed cutaneous:
- Itraconazole (drug of choice): Efficacious, but expensive and potential for hepatotoxicity, has numerous drug " drug interactions, black box in heart failure
- Terbinafine: Less expensive alternative if failure of itraconazole, only in cutaneous disease
- Saturated solution of potassium iodide (SSKI): Inexpensive but bitter taste and side effects (anorexia, nausea, diarrhea, fever, salivary gland swelling) lead to limited acceptability
- Local heat therapy for cutaneous disease (>35 °C) inhibits fungal growth, use in pregnant patients or others who cannot tolerate medication, therapy may take 3 " 6 mo
- Pulmonary:
- Itraconazole or amphotericin B in early disease, effective in ’ Ό30% of cases
- More advanced disease often requires resection plus amphotericin B
- Osteoarticular:
- Itraconazole: 1st-line therapy for more than 1 yr, amphotericin B if refractory
- Disseminated:
- Amphotericin initially
- Itraconazole in stable, immunocompetent patients
- HIV and sporotrichosis: Suppressive therapy with itraconazole is recommended after initial infection
Medication
- Amphotericin B: Lipid form 3 " 5 mg/kg daily (preferred, especially in pregnancy and peds); if using deoxycholate form (pt with no risk of renal dysfunction) 0.7 " 1 mg/kg daily and infuse over 2 hr
- Itraconazole: Lymphocutaneous: 100 " 200 mg (peds: 6 " 10 mg/kg/d, max. 400 mg) PO TID for 3 days, then 100 " 200 mg per day for 2 " 4 wk after lesions resolve, pulmonary/osteoarticular: 200 mg PO TID for 3 days, then BID for 12 mo
- SSKI: 5 drop (peds: 1 drop) in water or juice TID; increase by 5 drops per dose each week up to a max. 40 " 50 drops TID (peds: max. of 1 drop/kg) as tolerated, for 6 " 12 wk or until lesions resolve
- Terbinafine: Lymphocutaneous only: 250 " 500 mg PO per day for 2 " 4 wk after lesions healed
Follow-Up
Disposition
Admission Criteria
- Systemic signs/symptoms
- Pulmonary, CNS, multifocal disease
- Immunosuppressed host with disseminated disease
Discharge Criteria
Lymphocutaneous/fixed cutaneous form, nontoxic
Issues for Referral
Infectious disease consultant as appropriate
Followup Recommendations
Infectious disease specialist, dermatology, appropriate specialist given disease involvement (orthopedics, neurology)
Pearls and Pitfalls
Fixed cutaneous, lymphocutaneous, pulmonary, extracutaneous/disseminated disease secondary to S. schenckii:
- Inoculation with soil, moss, or organic material (skin break or inhalation)
- Contact with cats
- Healthy hosts develop fixed cutaneous/lymphocutaneous disease, immunocompromised hosts develop extracutaneous/disseminated disease
- Disseminated disease presents with nonspecific symptoms that often result in delayed diagnosis and poor outcome.
- Oral itraconazole is 1st-line therapy except for disseminated disease, where amphotericin is used initially
Additional Reading
- Barros MB, de Almeida Paes R, Schubach AO. Sporothrix schenckii and Sporotrichosis. Clin Microbiol Rev. 2011;24:633 " 654.
- Francesconi G, Valle AC, Passos S, et al. Terbinafine (250 mg/day): An effective and safe treatment of cutaneous sporotrichosis. J Eur Acad Dermatol Venereol. 2009;23:1273 " 1276.
- 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.
- Kauffman CA, Bustamante B, Chapman SW, et al. Clinical practice guidelines for the management of sporotrichosis: 2007 update by the Infectious Diseases Society of America. Clin Infect Dis. 2007;45:1255 " 1265.
- Tiwari A, Malani AN. Primary pulmonary sporotrichosis: Case report and review of the literature. Infect Dis Clin Prac. 2012;20:25.
Codes
ICD9
117.1 Sporotrichosis
ICD10
- B42.0 Pulmonary sporotrichosis
- B42.1 Lymphocutaneous sporotrichosis
- B42.9 Sporotrichosis, unspecified
- B42.82 Sporotrichosis arthritis
- B42.7 Disseminated sporotrichosis
- B42.81 Cerebral sporotrichosis
- B42.89 Other forms of sporotrichosis
- B42.8 Other forms of sporotrichosis
- B42 Sporotrichosis
SNOMED
- 42094007 Sporotrichosis (disorder)
- 45263007 Pulmonary sporotrichosis (disorder)
- 80890005 cutaneous sporotrichosis (disorder)
- 29081001 Sporotrichosis of the bones (disorder)