Application of nested PCR to detect Penicillium marneffei in serum samples.

We previously reported a nested PCR assay for specific identification of 18S ribosomal DNA of Penicillium marneffei. In this study, the assay was used to detect the DNA of P. marneffei in serum samples. Sensitivity of the test was 4 pg/microl and 0.4 fg/microl when the cycle numbers used for nested reactions were 15 and 30, respectively. Twenty four out of 35 sera (68.6%) collected from patients with culture confirmed penicilliosis marneffei were positive, while normal healthy and non-P. marneffei infected HIV-positive sera were negative. The results suggested that the assay could be applied for the diagnosis of infections due to P. marneffei.