Phialemonium fungemia: two documented nosocomial cases

Abstract

Two fungal isolates recovered from the blood of two immunosuppressed patients are described as Phialemonium curvatum. One patient died, while the other, who was infected with Exophiala jeanselmei at the same time, survived after successful treatment with itraconazole. Analysis of internal transcribed spacer sequences demonstrated that the isolates belonged to the same strain and that the source of infection was probably a catheter. The taxonomic position of P. curvatum is discussed, and Phialemonium dimorphosporum is considered a synonym. The in vitro inhibitory activities of six antifungal agents (amphotericin B, itraconazole, ketaconazole, miconazole, flucytosine, and fluconazole) were determined against seven isolates of Phialemonium. Except for flucytosine, all of them were remarkably effective. Phialemonium should be added to the list of potential causes of nosocomial fungemia in cancer patients.

FIG. 1

P. curvatum FMR 6321. (A) Conidiogenous cells and conidia. (B) Conidial morphology. Magnification, with Nomarski optics, ×1,600.

FIG. 2

(A) PCR products cleaved by CfoI and separated on a 2% agarose gel. Lane m, 100-bp DNA ladder (Gibco BRL) used as a size marker; lanes 1 and 4, P. dimorphosporum CBS 491.82 and FMR 3940, respectively; lanes 2 and 3, patient isolates FMR 6322 and FMR 6321, respectively; lane 5, P. curvatum CBS 490.82; lanes 6 and 7, P. obovatum CBS 730.97 and CBS 279.76, respectively. (B) PCR products cleaved by HinfI and separated on a 2% agarose gel. Lane m, 100-bp DNA ladder (Gibco BRL) used as a size marker; lanes 1 to 7 are as described above for panel A.

FIG. 3

Alignment of ITS1, 5.8S gene, and ITS2 of P. dimorphosporum CBS 491.82 and patient isolates FMR 6321 and FMR 6322. CBS 491.82 is used as the leading strand. Dots indicate nucleotides identical to the reference sequence (the CBS 491.82 sequence).