Talaromyces marneffei

Talaromyces marneffei (formerly known as Penicillium marneffei) is a thermally dimorphic fungus that can cause systemic mycosis in humans. It is endemic in Southeast Asia and Southern China, and is particularly associated with HIV-infected individuals.

Taxonomy[edit | edit source]

The fungus was first described in 1956 by Gabriel Segretain, who isolated it from a bamboo rat in Vietnam. It was initially classified in the genus Penicillium, but was later reclassified to the genus Talaromyces based on phylogenetic analysis.

Morphology[edit | edit source]

Talaromyces marneffei is a thermally dimorphic fungus, meaning it can exist in two different forms depending on the temperature. At room temperature (25°C), it grows as a mold with septate hyphae and produces conidia. At body temperature (37°C), it transforms into a yeast form.

Pathogenesis and Clinical Manifestations[edit | edit source]

Talaromyces marneffei can cause a systemic mycosis known as talaromycosis or Penicillium marneffei infection. This disease is most commonly seen in individuals with impaired immune systems, particularly those with HIV/AIDS. The fungus is inhaled and can spread throughout the body, causing a wide range of symptoms including fever, weight loss, skin lesions, and respiratory, gastrointestinal, and systemic problems.

Diagnosis and Treatment[edit | edit source]

Diagnosis of Talaromyces marneffei infection is typically made by identifying the fungus in clinical specimens such as blood, bone marrow, or tissue biopsies. Treatment usually involves antifungal medications, with amphotericin B and itraconazole being the most commonly used.

Epidemiology[edit | edit source]

Talaromyces marneffei is endemic in Southeast Asia and Southern China, and is particularly associated with HIV-infected individuals. The fungus has been isolated from various environmental sources, including soil and bamboo rats.