Development and evaluation of a one-tube seminested PCR assay for the detection and identification of Penicillium marneffei.

A one-tube seminested polymerase chain reaction (PCR) assay was developed to detect and identify Penicillium marneffei DNA coding for 18S rRNA both from purified DNA and from clinical samples. DNA from 120 strains of organisms and 19 blood samples from AIDS patients was amplified with F3, CPL1 and PM primers. Under optimized conditions, these primers detected 100% specifically amplified products of 251 and 331 bp from all P. marneffei DNA preparations (47 strains) and from two blood samples of AIDS patients suspected to suffer from penicilliosis marneffei. The assay was sensitive to detect as little as 10 pg purified DNA, which is equivalent to 250 cells. This PCR assay might be useful as an alternative test, if a rapid diagnosis of penicilliosis marneffei is needed.