Which fungi are dematiaceous?

A number of dematiaceous fungi are neurotropic, including Cladophialophora bantiana, Ramichloridium mackenziei, and Wangiella dermatitidis. Although cases have occurred in immunocompromised persons, cerebral phaeohyphomycosis is most common in immunocompetent individuals with no obvious risk factors.

Is Cladosporium dematiaceous fungi?

Cladosporium spp. are dematiaceous fungi usually identified as common airborne contaminants occupying a wide variety of habitats (9). This allergenic fungus has been reported to cause subcutaneous phaeohyphomycosis and intrabronchial lesions in immunocompetent individuals (6, 8).

Is Phialophora a dematiaceous fungi?

Phialophora richardsiae is one of the many dematiaceous fungi that can be isolated from plant material and soil9,11,12.

Why is histopathology an important method for the definitive diagnosis of fungal infections?

Because histopathologic examination of tissues detects fungal invasion of tissues and vessels as well as the host reaction to the fungus, it is and will remain an important tool to define the diagnostic significance of positive culture isolates or results from PCR testing.

Is Aspergillus a dematiaceous fungi?

(26.6%), Aspergillus spp. (21.6%), and Dematiaceous fungi (11.6%). The sequence of the ITS region could identify the Fusarium and Aspergillus species at the species complex level, and the Dematiaceous isolates were accurately identified.

Which of the following dematiaceous fungi can cause chromoblastomycosis?

Chromoblastomycosis is a chronic fungal infection of the skin and the subcutaneous tissue caused by traumatic inoculation of a specific group of dematiaceous fungi (usually Fonsecaea pedrosoi, Phialophora verrucosa, Cladosporium carrionii, or Fonsecaea compacta) through the skin.

What is histopathology used for?

Histopathology is the diagnosis and study of diseases of the tissues, and involves examining tissues and/or cells under a microscope. Histopathologists are responsible for making tissue diagnoses and helping clinicians manage a patient’s care.

Which stain is used for fungus?

Lactophenol cotton blue is a stain that is used to examine fungal elements following either a tape preparation or a scraping. This stain contains phenol, which will kill the organisms, lactic acid which preserves fungal structures, and cotton blue which stains the chitin found in the fungal cell walls.

What is Microconidia and Macroconidia?

A mass of hyphal elements is termed the mycelium (synonymous with mold). Aerial hyphae often produce asexual reproduction propagules termed conidia(synonymous with spores). Relatively large and complex conidia are termed macroconidia while the smaller and more simple conidia are termed microconidia.

What is mean chromoblastomycosis?

Chromoblastomycosis is a chronic fungal infection of the skin and subcutaneous tissue. The infection usually results from a traumatic injury and inoculation of microorganism from a specific group of dematiaceous fungi (usually Fonsecaea pedrosoi, Phialophora verrucosa, Cladophialophora carrionii).

Who discovered chromoblastomycosis?

The name “chromoblastomycosis” was employed for the first time in 1922 by Terra et al. to differentiate a cutaneous fungal disease observed in Brazil from the confusing clinical syndrome known as “verrucous dermatitis” (28).

What is histopathology laboratory?

A histopathology laboratory avails a number of services that involve examining the tissues and ultimately detect diseases. The complete range of services offered by laboratories include techniques like necropsy to sophisticated histological processing, as well as expert evaluation by pathologists.

What is biopsy in histopathology?

A biopsy is the surgical removal of a representative sample of tissue from a suspicious lesion. The biopsy is then processed and is examined under a microscope (see histopathology below).

Are fungi Gram positive or negative?

Gram staining is for bacteria differentiation either as positive or negative. Hence, bacteria classification can be based on such inference. Fungi can be detected using some staining agents such as Gram stain. But fungi (yeast & mold) cannot be classified as Gram positive or negative using such staining agent.

What is a fungal culture?

A fungal culture is a procedure used to determine if fungi are present in an area of the body. Fungi are microorganisms that thrive in moist, dark places, such as shoes, damp locker rooms, or the folds of the skin.

When are macroconidia formed?

In the environment and at temperatures lower than 35° C, it exists as a mold that produces conidia, both tuberculate macroconidia, which are helpful for identification purposes in the laboratory, and microconidia, which are the infectious form. In tissues and at 35 to 37° C, H.

Where is chromoblastomycosis found?

Chromoblastomycosis is encountered mainly in arid parts of tropical and subtropical regions. Most cases occur in Central and South America, but chromoblastomycosis has also been reported in South Africa, Asia and Australia.

What are dematiaceous fungi?

1 Division of Infectious Diseases, Department of Medicine, University of Texas Southwestern Medical Center and Dallas Veterans Affairs Medical Center, Dallas, TX, USA. [email protected] Dematiaceous fungi are responsible for a wide variety of infectious syndromes. They are often found in soil and generally distributed worldwide.

How is dematiaceous fungal infection diagnosed?

Currently, the diagnosis of infection due to dematiaceous fungi relies on pathologic examination of clinical specimens and careful gross and microscopic examination of cultures, occasionally requiring the expertise of a mycology reference lab for unusual or newly described pathogens.

What is the prognosis of dematiaceous fungal infections?

Most life-threatening infections due to dematiaceous fungi are seen in immunocompromised patients, with the possible exception of CNS infection. Therapy in patients with underlying diseases should be continued longer than in other patients and the use of surgery (when appropriate) should be strongly considered.

Are dematiaceous fungi susceptible to amphotericin B and miconazole?

Susceptibility of dematiaceous fungi to amphotericin B, miconazole, ketoconazole, flucytosine and rifampin alone and in combination. Sabouraudia 1982; 20:109-113.