Aspergillus Galactomannan Antigen in Liver Transplant Recipients (LTR): A High False-Positive Rate in Serum Samples Obtained During the First Week Post-Transplantation.

J. FORTUN, P. MARTíN-DíVILA, M. E. ALVAREZ, A. SíNCHEZ-SOUSA, L. GAJATE, R. BíRCENA, J. NUí‘O, S. MORENO;

Author address: 

Ramón y Cajal Hosp., Madrid, Spain.

Abstract: 

Background: Aspergillus antigenemia (AspAg) is a useful tool as early marker of pts at risk to develop invasive aspergillosis (IA), but it could have false-positive (FP) results. The causes of FP reported are varied like some foods, altered intestinal barrier, other types of fungi and semi-synthetic β -lactam treatments, especially piperacillin-tazobactam. Methods: From jul-03 to Apr-07, a prospective study, testing periodically AspAg in serum samples of liver transplant recipients (LTR), was performed in our Institution. Plateliaâ„¢ Aspergillus EIA-sandwich microplate assay was used following the manufacturer recommendations. Samples with an index ≥ 0.5 were considered positive. AspAg test was performed weekly during the first 2 months after transplantation and monthly after discharge until month +6. Results: A total of 461 serum samples from 92 LTR were analyzed. Mean number of samples per patients was 5 (median:3.5). The number of positive samples were 41, corresponding to 33 pts. During this period, 3 pts (3,2%) had a diagnosis of IA and AspAg were positive in 2 of them. Prophylaxis with caspofungin was administered in 18 pts at high risk for fungal infections according to specific criteria. Five of these 18 pts have had positive AspAg and aspergillosis could not be excluded. The frequency of FP in our samples was 6.5% (30/461). The rate of FP results in the samples obtained during the 1st week post-transplantation was 28.7% (23/80); in contrast to 2.4% (9/381) of FP results in samples obtained after the first week (p
2007

abstract No: 

K-2167

Full conference title: 

47th Interscience Conference on Antimicrobial agents and Chemotherapy
    • ICAAC 47th