title: Phaeoacremonium parasiticum invasive infections and airway colonization characterized by agar block smear and ITS and β-tubulin gene sequencing.
abstract: Phaeoacremonium parasiticum is an environmental dematiaceous mold rarely associated with human infections. We present here 2 cases of P. parasiticum invasive infections, including the first report of P. parasiticum respiratory tract infection, and 1 case of airway colonization, which all 3 strains of P. parasiticum were identified using agar block smear and ITS and β-tubulin gene sequencing. All 3 isolates grew initially as white to creamy, yeast-like colonies. After 21 days of incubation at 25 °C, 1 isolate remained light brown, atypical of P. parasiticum. Microscopic examination of agar block smear preparations of all 3 isolates showed thick-walled, medium brown conidiophores that were branched and slightly swollen at the base. The sequences of the ITS and β-tubulin genes of the 3 isolates were identical to those of P. parasiticum. Cases of P. parasiticum infections should be confirmed by a polyphasic approach using morphologic characterization and ITS and β-tubulin gene sequencing.
authors.affiliation: Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong, China.
authors.forename: Kelvin K W
authors.initials: KK
authors.lastname: To
authors.forename: Susanna K P
authors.initials: SK
authors.lastname: Lau
authors.forename: Alan K L
authors.initials: AK
authors.lastname: Wu
authors.forename: Rodney A
authors.initials: RA
authors.lastname: Lee
authors.forename: Antonio H Y
authors.initials: AH
authors.lastname: Ngan
authors.forename: Chris C C
authors.initials: CC
authors.lastname: Tsang
authors.forename: Ian W H
authors.initials: IW
authors.lastname: Ling
authors.forename: Kwok-Yung
authors.initials: KY
authors.lastname: Yuen
authors.forename: Patrick C Y
authors.initials: PC
authors.lastname: Woo
mesh_terms: D000328:Adult; D000362:Agar; D000368:Aged; D001203:Ascomycota / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D003470:Culture Media / Q000737:chemistry; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D006801:Humans; D008297:Male; D008853:Microscopy; D008969:Molecular Sequence Data; D009181:Mycoses / Q000175:diagnosis* / Q000382:microbiology*; D010802:Phylogeny; D012141:Respiratory Tract Infections / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D014404:Tubulin / Q000235:genetics
chemical_list: D003470:Culture Media; D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer; D014404:Tubulin; D000362:Agar