COMPARISON OF AN ENZYME-IMMUNOASSAY AND LATEX AGGLUTINATION-TEST FOR DETECTION OF GALACTOMANNAN IN THE DIAGNOSIS OF INVASIVE ASPERGILLOSIS

Aspergillus antigenemia was followed up in 215 consecutively observed bone marrow transplant (BMT) patients over a period of two years, usin g both a latex agglutination test and a sandwich immunocapture enzyme immunoassay (EIA) with a rat anti-galactomannan monoclonal antibody as capture and detector antibody. For each patient, sequential sera (3 t o 20) were obtained before and after BMT. No positivity was observed b efore BMT After BMT, the EIA and latex agglutination test were positiv e in 19 and 4 patients respectively of 25 patients with confirmed aspe rgillosis and 14 and 7 of 15 patients with probable aspergillosis. In 19 of 25 patients with confirmed aspergillosis and 9 of 15 patients wi th probable aspergillosis, the EIA was more sensitive and detected inf ection earlier than the latex test. In all positive cases, antigenemia rapidly increased in sequential samples and remained strongly positiv e. In 31 of 169(19%) BMT patients without clinical signs of aspergillo sis, the EIA was occasionally positive in samples taken within the fir st month after BMT, giving a specificity of 81% in these patients. In non-BMT patients suffering from other diseases (n = 77), the specifici ty was 98.7%. The overall positive and negative predictive values for the EIA were 54% and 95% respectively. These results favour the use of EIA for early diagnosis and monitoring of aspergillosis in BMT patien ts, although the predictive value of transient positivity remains to b e ascertained.