Detection of Aspergillus galactomannan antigen levels for antimicrobial agents by ELISA

Abstract number: p869

Yucesoy  M., Ergon  M.C.


False positive results in Aspergillus galactomannan antigen detection by ELISA method from patients receiving piperacillin-tazobactam have been reported. In this study, we aimed to investigate A. galactomannan antigen levels for piperacillin-tazobactam and other various antimicrobial agents that are often used for the treatment of infections in immunocompromised patients.


The level of galactomannan antigen was investigated for piperacillin-tazobactam, ampicillin-sulbactam, ampicillin, penicillin G, ceftriaxone, cefepime, imipenem, clarithromycin, ciprofloxacin, vancomycin, gentamicin, trimethoprim-sulfamethoxazole, ornidazole, fluconazole and amphotericin B. Antigen levels were determined by using the Platelia Aspergillus ELISA (Bio-Rad, France) according to the manufacturer's instructions. Samples were run in triplicate and the entire experiment was repeated.


Among the 15 antibiotics, ampicillin expressed highest level of galactomannan with a galactomannan index (GI) of 0.540. Although this index value is not a positive result for the presence of galactomannan according to the manufacturer's instructions, it can be accepted as positive according to the test products with FDA approval. Piperacillin-tazobactam expressed the second high level of galactomannan (GI = 0.235), however this value is below the both cutoff limits. Galactomannan levels for the other antibiotics ranged from 0.011 to 0.188.


It can be concluded that among the antibiotics that was investigated in this study, ampicillin might cause a false positive result in galactomannan antigen test by ELISA because it showed significant level of galactomannan antigen and piperacillin-tazobactam can also cause cross reactivity in the sera of patients due to its relatively high galactomannan level in the test.

Session Details

Date: 01/08/2007
Time: 00:00-00:00
Session name: XXIst ISTH Congress
Location: Oxford, UK
Presentation type:
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