Phaeohyphomycosis

Phaeohyphomycosis is caused by opportunistic molds that have dark cell walls. Initial symptoms are a skin or subcutaneous nodule, abscess, sinusitis, or brain abscess. Eumycetoma and chromoblastomycosis are acquired by skin penetration with most infections occurring in tropical, rural areas.

CASES/YEAR
500 (US); 10,000 (Global)
CATEGORY
Sapronoses
AGENT TYPE
Fungi (Opportunistic Molds)
OTHER NAMES
Dematiaceous fungal infections;
ACUITY
Subacute/Chronic
INCUBATION
Estimated: days to weeks;
INITIAL SYMPTOMS
Skin or subcutaneous nodule or abscess; Sinusitis; Brain abscess;
PRECAUTIONS
COMMENTS
Dematiaceous fungi include eumycetoma (mainly Madurella species and Scedosporium species) chromoblastomycosis (mainly Fonsecaea and Cladophialophora species), and disseminated infections (including Alternaria, Exophiala, Curvularia, and Wangiella species). In Dematiaceous fungi, hyphae and/or conidia are black or brown because they contain melanin pigment. Eumycetoma and chromoblastomycosis are acquired by skin penetration with most infections occurring in tropical, rural areas. Several dematiaceous fungi are neurotropic and cause CNS infections. Others cause allergic fungal sinusitis, invasive fungal sinusitis, keratitis, and pneumonia. [Harrison ID, p. 1027]

Phaeohyphomycosis is loosely defined and includes molds and a few yeasts with dark cell walls. Mycetoma and chromoblastomycosis are not generally included. Disseminated diseases occur mainly in immunosuppressed patients: meningitis, pneumonia, endocarditis of prosthetic valves, peritoneal dialysis catheter infection, osteomyelitis, and septic arthritis. Most patients with brain abscesses have been immunocompetent. One of the sequelae of allergic fungal sinusitis, usually seen in immunocompromised hosts, is invasive disease with proptosis, sudden blindness, and brain abscesses. [PPID, p. 3225-8]

As of 1998, more than 109 species and 60 genera of fungi were known to cause phaeohyphomycosis, characterized by dark-colored filamentous hyphae in tissue. Cutaneous and subcutaneous nodules and abscesses, sometimes containing the inciting splinter, are the most common diseases. Verrucous nodules and plaques are seen less frequently. About 1/2 of patients are immunocompromised. Lymphadenopathy and dissemination are rare, but infections of the CNS, liver, lungs, pancreas, and other organs do occur. [Guerrant, p. 571-2] See "Mycetoma" and "Chromoblastomycosis."
DIAGNOSTIC
Eumycetoma: swelling, sinus tracts, and grains; Chromoblastomycosis: sclerotic bodies in the tissue samples; Disseminated & nonsubcutaneous focal infections: culture to distinguish from Aspergillus, Fusarium, etc. [Harrison ID, p. 1027]
SCOPE
Global
SIGNS & SYMPTOMS
  • >fever
  • E nasal ulcers
  • E rhinitis
  • N headache
  • N muscle weakness
  • N seizure
  • N stiff neck
  • 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
  • *arthritis
  • *blindness
  • *brain abscess or lesion
  • *endocarditis
  • *meningitis
  • *osteomyelitis
  • *paralysis
  • *pneumonia
ANTIMICROBIC

Yes

VACCINE

No

ENTRY
Inhalation, Skin or Mucous Membranes (Includes Conjunctiva)
SOURCE
Soil or Dust (Ingesting or Inhaling)
RESERVOIR
RISK FACTORS
  • AIDS patients
  • Cancer patients
  • Walk barefooted in contaminated soil
TREATMENT
"Surgical debridement is essential to the cure of most of the infections caused by the dark-walled fungi." [PPID, p. 3228]
DRUG LINK
Merck Manual: Phaeohyphomycosis
REFERENCES FOR CASES/YEAR
1. (US) No data found; Assume same cases/yr as Mucormycosis;
2. (Global) No data found; Assume same rate as Mucormycosis;