Prospective screening in liver transplant recipients by panfungal PCR-ELISA for early diagnosis of invasive fungal infections

Abstract

Invasive fungal infections after liver transplantation (LT) have resulted in high mortality and potentially fatal complications. This study was undertaken to determine the accuracy of the panfungal polymerase chain reaction enzyme link immunosorbent assay (PCR-ELISA) method in early diagnosis of invasive fungal infections in liver transplant recipients (LTRs). A total of 48 liver recipients (cadaver donors) were followed for fungal infections for a period of at least 6 months. All clinical samples were cultured and a direct microscopic examination was performed. Blood samples were cultured by bedside inoculation onto BACTEC medium. Whole blood specimens were collected prospectively once per week and were evaluated for any invasive fungal infections by panfungal PCR and PCR-ELISA. Among 48 transplant recipients between September 2004 and January 2006 (22 females, 28 males, mean age ϭ 34.4 yr), 40 recipients (83.3%) had Candida colonization in different sites of their body before LT. In proven and probable recipients for panfungal PCR-ELISA, the sensitivity, specificity, and positive and negative predictive values were 83.3%, 91.7%, 76.9%, and 94.3%, respectively. By PCR assay, fungal infections were diagnosed in 10 recipients (20.8%). The mean interval time from transplantation to development of fungal infection was 61.4 days (range, 20-150 days) and time of infection in blood before any clinical signs was 7-70 days with mean of 21.4 days. The etiologic agents were Candida albicans (9 cases) and Aspergillus fumigatus (1 case). Use of PCR-ELISA in LTRs may not only improve the ability of early diagnosis of invasive fungal infections (IFIs) when positive results are obtained, but also would provide more confidence to exclude a diagnosis of IFIs when negative results are obtained.

Molecular and Nonmolecular Diagnostic Methods for Invasive Fungal Infections

“…In such cases, PCR facilitates species identification, which cannot be achieved through microscopy but can serve an important role in guiding antifungal therapy. Multiplex PCR has also been tested as a method to detect fungal species in whole-blood (236,238,(243)(244)(245), serum (246), or BAL fluid (247) samples from patients at high risk for IFIs. The results are variable, but most studies report superior sensitivities and specificities of Ͼ80% (236,238,243,248).…”

Value of Serial Quantification of Fungal DNA by a Real-Time PCR-Based Technique for Early Diagnosis of Invasive Aspergillosis in Patients with Febrile Neutropenia

“…For this purpose, serial detection techniques have been developed for fungal components and used with blood or serum samples from patients at risk of mycosis (5,7). This strategy has been little used in the detection of fungal DNA, and only some studies have analyzed serial samples of serum/blood to detect Candida or Aspergillus (1,3,8,10). In general, the serial detection of Aspergillus DNA has had a low PPV (17 to 66%), which rose when two consecutive positive samples were used as the diagnostic criterion.…”

Molecular diagnosis of Aspergillus endocarditis after cardiac surgery

“…Molecular identification of fungal infections has typically been presented in other research (Imai et al, 2000;Posteraro et al, 2000;Löffler et al, 1998;Einsele et al, 1997). A PCR assay for the detection of fungal nucleic acids may be the optimal diagnostic approach, because it offers the potential of being more sensitive than current culture-based methods and more applicable to a variety of specimen types (Van Burik et al, 1998;Badiee et al, 2007). A molecular approach to improve the microbiological diagnosis is reported in valvular heart disease cases by Breitkopf et al (2005).…”