Screening of invasive fungal infections by a real time panfungal (PAN-ACF) PCR assay in patients with haematological malignancy

Malini R Capoor*. Shika Arora Puria, Dinesh K Guptab, Harish Chand Sachdevac and Pradeep KumarVermac

Author address: 

Department of Microbiology, Intensive Care Unit (ICU), Hematology, VMMC and Safdarjung Hospital, Delhi-110 029

Abstract: 

Invasive fungal infection (IFI) is a fatal infection in haematology patients. There is an urgent need for reliable screening methods facilitating timely diagnosis and treatment. Areal time pan fungal PCR assay based on Taq man technology targeting 18 S ribosomal RNA gene was used to screen whole blood specimen obtained from series of haematology malignancy patients for IFIs. The pan fungal (Pan-ACF) assay was employed to investigate specimen from 133 patients in duplicate with suspected IFI. In addition 20 healthy subjects and 20 patients with bacterial infections were taken as control. The patients with suspected IFI were also diagnosed by conventional methods including direct microscopy, culture techniques and antigen detection. The results of molecular testing were evaluated in relation to the revised criteria proposed by EORTC and patients were classified as having proven and probable IFD. Of 133 patients, 89 had proven, 18 had probable and 26 had possible IFI. One-hundred-four samples were RT-PCR positive. Of 89 proven cases, 84 were panfungal PCR positive. These 84 cases included 82 cases which revealed growth on fungal blood culture and two cases were negative on fungal blood culture. Of the 82 cases which revealed growth on culture: 74 grew Candida in culture, 3 grew Fusarium solani, 5 grew Aspergillus species on blood culture (galactomannan antigen positive). The 5 specimen which were negative on pan fungal PCR, 2 grew T. ashaii. 1 grew C. rugosa, and 2 grew as C. neoformans var. neoformans. Of the 18 probable cases, 18 were panfungal PCR positive. These were also galactomannan antigen positive. The sensitivity, specificity, positive predictive value and negative predictive value of pan fungal PCR in proven cases was 94.3%, 95.2%, 97.6% and 88.9%, respectively. The pan fungal (Pan-ACF) real-time PCR assay can detect common fungal genera and it may be used as an adjunct to conventional methods for screening of invasive fungal infection. 9830;Corresponding author E-mail:[email protected]
2014

abstract No: 

OP-020

Full conference title: 

Society for Indian Human and Animal Mycologists 2014
    • SIHAM