What disease is caused by Penicillium marneffei?
Penicillium marneffei is an emerging pathogenic fungus that can cause a fatal systemic mycosis in patients infected with human immunodeficiency virus (HIV).
What is Penicilliosis?
Penicilliosis, disseminated infection with the fungus Penicillium marneffei, has become an important opportunistic infection in AIDS patients in southeast Asia (especially northern Thailand) and southern China. The disease usually occurs when CD4 T-cell counts fall below 50 cells/μL.
Where is Talaromyces marneffei found?
Talaromyces marneffei is endemic in Myanmar (Burma), Cambodia, Southern China, Indonesia, Laos, Malaysia, Thailand and Vietnam. Although both the immunocompetent and the immunocompromised can be infected, it is extremely rare to find systemic infections in HIV-negative patients.
Is Penicillium a dimorphic fungi?
Penicillium marneffei is a pathogenic fungus that afflicts immunocompromised individuals having lived or traveled in Southeast Asia. This species is unique in that it is the only dimorphic member of the genus. Dimorphism results from a process, termed phase transition, which is regulated by temperature of incubation.
How is Penicilliosis transmitted?
marneffei, the etiological fungus of talaromycosis is transmitted to human through inhalation of spores from soil. It then spreads to the reticuloendothelial system, skin and other organ system through the hematogenous route.
What is meant by thermal dimorphism?
The thermally dimorphic fungi are a unique group of fungi within the Ascomycota phylum that respond to shifts in temperature by converting between hyphae (22–25°C) and yeast (37°C). This morphologic switch, known as the phase transition, defines the biology and lifestyle of these fungi.
What is meant by dimorphic fungus?
Abstract. Dimorphic fungi are organisms that have the ability to switch between two morphologies during their lifecycle: yeast and hyphae. In thermal-dimorphic fungi, morphologic changes are induced by temperature.
Is Penicillium marneffei dimorphic?
Penicillium marneffei is a dimorphic fungus endemic in South-east Asia. 219 At room temperature it grows as a mould with red to black conidia whereas in tissue it forms a 3–5-µm yeast-like cell that divides by binary fission. The yeasts therefore display clear central septation, unlike H. capsulatum and other fungi that divide by budding.
Where does Penicillium marneffei produce its toxin?
The production of the toxin usually occurs in cereal grains at cold climates [ 1804 ]. Penicillium marneffei is a pathogenic fungus and specifically infects patients with AIDS who live at or visit Southeast Asia (Thailand and adjacent countries, Taiwan, and India) where the fungus is endemic [ 565, 2114, 2200 ].
Can Penicillium marneffei be induced to produce arthroconidial yeast-like structures?
Penicillium marneffei is easily induced to produce the arthroconidial yeast-like state by subculturing the organism to an enriched medium like BHI and incubating at 35°C, in which after a week, yeast-like structures dividing by fission and hyphae with arthroconidia are formed [ 531, 1295, 2144, 2202 ].
How is Penicillium marneffei (PMS) infection diagnosed?
The diagnosis of infection due to P. marneffei rests on the histopathologic demonstration of cells multiplying by fission in the interior of leukocytes. HABITAT Penicillium are cosmopolitan, predominant in regions of temperate climate.
