Galactomannan antigen test

Galactomannans are starch-like substances consisting of branched carbohydrate chains. The main chain consists of mannose, with short side chains of one galactose molecule each glycosidically bound at different intervals. This structure is characteristic for legume mucus (galactomann). Galactomanne are important structural elements in Aspergillus spp.

Galactomannan antigen test detects even low concentrations of galactomannan. A positive test result indicates the presence of invasive aspergillosis (B44.9). Immunocompromised patients undergoing chemotherapy, after organ and bone marrow transplantation and high-dose glucocorticosteroid administration are particularly at risk. If the result is positive, the result should be confirmed in another sample.

However, the antigen detection is not specific for Aspergillus species.

Galactomannan may be obtained from serum, CSF or bronchoalveolar lavage fluid. In high-risk patients the infection can be detected by serial antigen detection (at least twice a week), before clinical or radiological signs appear.