Rapid identification of Histoplasma capsulatum directly from cultures by multiplex PCR.

NAHUEL ELÍAS; MARÍA L CUESTAS; MACARENA SANDOVAL; GABRIELA POBLETE; GABRIELA LÓPEZ-DANERI; VIRGINIA M JEWTUCHOWICZ; CRISTINA IOVANNITTI; MARÍA T MUJICA

MYCOPATHOLOGIA

SPRINGER

Lugar: Berlin; Año: 2012 vol. 174 p. 451 - 456

0301-486X

Mycopathologia. 2012 Dec;174(5-6):451-6. doi: 10.1007/s11046-012-9567-2. Epub 2012 Jul 21. Rapid identification of Histoplasma capsulatum directly from cultures by multiplex PCR. Elías NA, Cuestas ML, Sandoval M, Poblete G, Lopez-Daneri G, Jewtuchowicz V, Iovannitti C, Mujica MT. Source Departamento de Microbiología, Parasitología e Inmunología, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155 piso 11, 1121 Buenos Aires, Argentina. Abstract The multiplex PCR developed from a suspension of the yeast fungi correctly identified fifty-one clinical of H. capsulatum var. capsulatum strains isolated from clinical samples and soil specimens. The multiplex PCR was developed by combining two pairs of primers, one of them was specific to the H. capsulatum and the other one, universal for fungi, turned out to be specific to H. capsulatum, regardless of the fungus isolate studied. Primers designed to amplify a region of about 390-bp (Hc I-Hc II) and a region of approximately 600-bp (ITS1-ITS4) were used to identify a yeast isolated as H. capsulatum when both regions could be amplified. Absolute agreement (100 % sensitivity) could be shown between this assay and the cultures of H. capsulatum according to their morphological characteristics. Failure to amplify the target DNA sequence by PCR with primers Hc I-Hc II in the presence of the ITS1-ITS4 amplicon in isolates of P. brasiliensis, Cryptococcus neoformans, Trichosporon spp, Candida glabrata, C. albicans, C. tropicalis, C. parapsilosis, C. krusei, or Penicillium marneffei was an unequivocal sign of the high specificity of this assay. The assay specificity was also found to be 100 %. Incipient yeast forms obtained from clinical samples were identified as H. capsulatum by the PCR assay described before the morphological characteristics were registered shortening the time of diagnosis.