Fungus
Talaromyces marneffei
Southeast Asian dimorphic fungus; fission yeast
tal-uh-ROH-mih-seez mar-NEF-eye
High-yield clue
Yeast dividing by fission (a transverse septum, not budding) plus red diffusible pigment in mold culture from a Southeast Asian HIV patient is the core study clue.
Overview
A thermally dimorphic fungus (formerly Penicillium marneffei) endemic to Southeast Asia and southern China that causes talaromycosis, an important opportunistic infection in advanced HIV. Classic geographic dimorphic-fungus teaching organism of Southeast Asia.
Classification
- Thermally dimorphic fungus
- Mold at 25C, yeast at 37C
- Yeast divides by transverse binary fission (a central septum), not budding
- Ascomycota (formerly Penicillium marneffei)
- Endemic to Southeast Asia
Lab & identification clues
- Intracellular fission yeast with a central septum vocabulary
- Mold form produces a diffusible red pigment in agar vocabulary
- Penicillus (brush-like) conidiophore in mold phase
- Recovered from blood, marrow, or skin lesions in coursework
Associations
- Talaromycosis in advanced HIV/low CD4 vocabulary
- Endemic to Vietnam, Thailand, and southern China
- Bamboo rats as environmental reservoir association
- Umbilicated (molluscum-like) skin papules teaching vocabulary
Commonly confused with
- Histoplasma capsulatum (small intracellular yeast)
- Cryptococcus (encapsulated yeast)
Frequently asked questions
What is Talaromyces marneffei?
A thermally dimorphic fungus (formerly Penicillium marneffei) endemic to Southeast Asia and southern China that causes talaromycosis, an important opportunistic infection in advanced HIV. Classic geographic dimorphic-fungus teaching organism of Southeast Asia.
What are the lab clues for Talaromyces marneffei?
Lab clues for Talaromyces marneffei include Intracellular fission yeast with a central septum vocabulary; Mold form produces a diffusible red pigment in agar vocabulary; Penicillus (brush-like) conidiophore in mold phase; Recovered from blood, marrow, or skin lesions in coursework.
What is Talaromyces marneffei commonly confused with?
Talaromyces marneffei is commonly confused with Histoplasma capsulatum (small intracellular yeast) and Cryptococcus (encapsulated yeast).
Original student-study summary. Sources checked: OpenStax Microbiology 2e, NCBI Bookshelf Medical Microbiology, and CDC topic pages where applicable; reviewed 2026-06. Educational only; no diagnosis, treatment, dosing, or specimen-handling guidance.