This document provides an overview of chromoblastomycosis and phaeohyphomycosis. Chromoblastomycosis is caused by fungi of the order Chaetothyriales and presents as chronic, progressive skin lesions on exposed areas of the body. Phaeohyphomycosis is caused by various pigmented fungi and can manifest as cutaneous, subcutaneous, or systemic infections. Both conditions are diagnosed through microscopy, culture, and histopathology of lesions. Treatment involves antifungal medications, surgery, or a combination depending on the severity and location of the infection.

1. Prepared by: Addisu Tesfaye
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2. Outline
• Introduction
• Chromoblastomycosis
• Phaeohyphomycosis
• Summary
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3. OBJECTIVE
• At the end of these presentation you should be able to describe
Etiology
 Epidemiology
Clinical Presentation
Pathogenesis
 Lab Diagnosis, and
 Treatment of Chromoblastomycosis And Phaeohypomycosis
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4. INTRODUCTION
• Dematiaceous, or Pigmented Fungi
100 species and 60 genera (Matsumoto et al, 1994).
have been identified in human disease
• The common forms are filamentous fungi or molds
• Pheoid fungi can cause :
 Eumycetoma,
Chromoblastomycosis, and
 Phaeohypomaycosis(Jacobson, 2000).
• The unique characteristic they shared is
Presence of melanin in their cell walls.
This gives dark color to their conidia or spores and hyphae
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5. CHROMOBLASTOMYCOSIS
DEFNITION
• Chromoblastomycosis is fungal infection of the skin and subcutaneous tissues
Granulomatous
Chronic
 Progressive
 Cutaneous and Subcutaneous fungal infection
• Also known as Chromomycosis or Fonseca's disease
• These organisms are called dematiaceous fungi
They have a black color in the mycelium cell wall (in culture and in tissue).
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6. CHROMOBLASTOMYCOSIS CONT…
Epidemiology and etiology of chromoblastomycosis
• The etiological agents of chromoblastomycosis belong to
Order Chaetothyriales,
Family Herpotrichiellaceae
• The most common of the etiologic agents are
Cladophialophora carrionii
 Fonsecaea pedrosoi
• Less common pathogens include
Fonsecaea compactum
Phialophora verrucosa
 Exophiala jeanselmei
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7. CHROMOBLASTOMYCOSIS CONT…
• Chromoblastomycosis:-
 Distributed world widely
 Most common in tropics and subtropics between 30° N and 30°S(Brito and
Bittencourt, 2018)
 Mainly apparent often in rural areas
 Most frequently occurs in males
 It mostly affects lower limbs, especially feet, which are most frequently exposed to
contact with the infected material
 Saprophytes of soil, decaying vegetation and rotting woods
 Enter skin through abrasion, often by thorns or splinters.
Rise in global temperature, and increase in
emigrants, immigrants, and travelers, cases of
CBM are spreading temperate regions
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8. CHROMOBLASTOMYCOSIS CONT…
Pathogenesis
• In the host, the propagules adapt to the tissue environment through the
dimorphism.
• They form the filamentous phase in globe-shaped structures called muriform
cells
• Significant factors for the pathogenicity of Chromoblastomycosis and Phaeohyphomycosis
include:
Melanin
Muriform cells
Cell adhesion, and
 Hydrophobicity.
• DHN melanin- fungal armor in cell wall
Scavenge free radicals
Prevents action of hydrolytic enzymes8/13/2020 8

9. CHROMOBLASTOMYCOSIS CONT…
• The immune response in these fungal infections include:
Cellular, involving macrophages
 Langerhans cells and
the humoral response(Brito and Bittencourt, 2018)
Clinical presentation of Chromoblastomycosis
• A previous unnoticed or unremembered trauma to the skin is often the site of
infection.
• Patients are usually asymptomatic. Patients visit hospital only in cases of
secondary infection or elephantiasis.
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10. CHROMOBLASTOMYCOSIS CONT…
• After several years a
Small,
 Raised,
Erythematous,
Asymptomatic Papule Develops, known as Verrucous Lesions
• The verrucous Lesions spread laterally to contiguous healthy tissue.
• The verrucous lesions are frequently ulcerated and may be raised about 1 to 3 cm
above the skin surface with rough irregular surfaces, giving a cauliflower like
appearance and hence it is also called as verrucosa dermatitis.
• Complications include elephantiasis, 2° infection, ulceration & malignant change
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11. CHROMOBLASTOMYCOSIS CONT…"Chromoblastomycosis;
hyperkeratotic lesions foot
and hand; Fonsacaea
(Phialophora) infection,
Cauliflower
appearance
lesion
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12. CHROMOBLASTOMYCOSIS CONT…
Laboratory diagnosis Chromoblastomycosis
Direct microscopy
(KOH) 10-20% of skin scraping, crusts, aspiration and biopsy tissue reveals
muriform (sclerotic) bodies.
• Culture: Sabouraud dextrose agar , 4-6 weeks, 37°C
F. pedrosoi produces velvety, dark-brown, olive-green, or black colonies.
Phialophora verrucosa produces slow-growing, velvety, moss-green, brown, or
black colonies.
 C. carrionii displays colonies very similar to those of F. pedrosoi. R. aquaspersa
colonies are velvety and moss-green to black
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13. CHROMOBLASTOMYCOSIS CONT…
• Histopathology: H and E stain of Biopsy specimen
Sclerotic bodies / muriform cells
Treatment and prevention of Chromoblastomycosis
• The several treatment options include medication and surgery.
• Treatment options include oral &locally applied itraconazole, heat therapy,
cryosurgery, laser therapy& surgery
• Surgical excision of an early solitary lesion is preferred
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14. PHAEOHYPHOMYCOSIS
DEFNITION
• The term phaeohyphomycosis comes from the Greek phaios, meaning dark or darkish
• A mycotic infection of humans and lower animals
• Based upon the level of involvement in the host, there are four basic forms
 Superficial
 Cutaneous and corneal,
Subcutaneous, and
 Systemic Phaeohyphomycosis (Jeragh et al, 2019)
• This entity is characterized by dark septate hyphae, pseudohyphae, yeast or their
combinations.
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15. PHAEOHYPHOMYCOSIS CONT…
Epidemiology and Etiology of Phaeohyphomycosis
• Phaeohyphomycosis is caused by ubiquitous pigmented fungi that belong to
several genera. Most common are:
Exophiala jeanselmei
Wangiella dermatitidis
 Phialophora verrucosa
Bipolaris spp
• They live in decaying vegetation, bird nests and soil
• PHM lesions may occur anywhere in the body, often in exposed parts
• Infection is by local trauma by abrasion or inhalation
• They are seen mostly in tropics and subtropics8/13/2020 15

16. PHAEOHYPHOMYCOSIS CONT…
Clinical presentation of Phaeohyphomycosis
• The most common and typical lesions are cutaneous or subcutaneous cysts or
abscesses, frequently caused by E. jeanselmei
• The primary lesion occurs as a
• Single
• Discrete
• Asymptomatic small nodule
• This is palpable under the smooth and slightly elevated skin.
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17. PHAEOHYPHOMYCOSIS CONT…
• The commonest sites of infection are the
• Feet,
• Legs,
• Hands,
• Arms, and
• Head
• If left untreated, the nodule will slowly increase in size to form a painless cystic abscess
• The overlying epidermis is hardly affected, and the formation of a sinus tract or ulceration is
rarely observed.
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18. PHAEOHYPHOMYCOSIS CONT…
• Granulomatous, slightly elevated plaque may appear when the lesion's main site is in the
epidermis and dermis
• Lymph node involvement and dissemination are rare. However, PHM may occur in the
central nervous system or other internal organs
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19. PHAEOHYPHOMYCOSIS CONT…Alternaria sp.
colonizing a tomato
showing typical darkly
Pigmented
(dematiaceous) lesions.
phaeohyphomycosis of the face
caused by Wangiella
dermatitidis
phaeohyphomycosis of the
forearm caused by
Exophiala jeanselmei
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20. PHAEOHYPHOMYCOSIS CONT…
Laboratory diagnosis phaeohyphomycosis
Direct microscopy
• KOH of pus, drainage or skin scaping
 Pigmented yeasts, pseudohyphae and hyphae
• Culture technique
• PHM agents grow well on routine fungal media such as Sabouraud dextrose
agar, cornmeal agar, malt extract agar, and potato dextrose agar
Grow in temperatures higher than 37°C
Their colonies in culture appear olivaceous green to brown or black.8/13/2020 20

21. PHAEOHYPHOMYCOSIS CONT…
Histopathology
• Pigmented fungi with inflammatory cells
• Biopsy
 Pigmented fungi seen within granuloma
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22. PHAEOHYPHOMYCOSIS CONT…
Treatment and prevention phaeohyphomycosis
• There is no standard therapy for the treatment of Phaeohyphomycosis; rather, it depends
on the patient's clinical syndrome and status
• For subcutaneous nodules, surgery alone may be curative, but Itraconazole has excellent
activity
• If it is brain abscess or disseminated infections, a combination of antifungal drugs is
used, at least one of which is an azole.
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23. SUMMARY
• Pheoid fungi can cause three different main types of subcutaneous infections: eumycetoma,
Chromoblastomycosis, and Phaeohyphomycosis
• Chromoblastomycosis and Phaeohyphomycosis are fungal infections following the traumatic
implantation of certain dematiaceous fungi
• Chromoblastomycosis is often a local cutaneous and subcutaneous infection that usually
occurs in immunocompetent hosts, while Phaeohyphomycosis manifests cutaneous,
subcutaneous, and systemic diseases that commonly develop in immunocompromised patients.
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