Using the galactomannan antigen assay in the diagnosis of invasive aspergillosis after hematopoietic stem cell transplantation

Abstract

Invasive aspergillosis (IA) is the most common life-threatening infections after hematopoietic stem cell transplant (HSCT). The serum galactomannan (GM) is recognized as an indirect mycological criteria for an early diagnosis of IA. Starting January 2011, we implementing in Fundeni Clinical Institute, Bucharest, for the first time in Romania, the detection of GM antigen (Platelia Aspergillus EIA, Bio-Rad). In 2011, patients undergoing HSCT were screened with the galactomannan ELISA; we performed a retrospective chart review of 162 SCT patients who underwent galactomannan testing. Thirteen of the patients (8.02%) had at least one positive galactomannan ELISA, and four had multiple positive tests. When calculated in reference to a proved or probable diagnosis of aspergillosis, the galactomannan ELISA had a sensitivity of 0.857 and a specificity of 0.913. The positive predictive value was 0.46, and the negative predictive value was 0.993. The Platelia Aspergillus galactomannan antigenemia assay may assist physicians in making an early diagnosis of IA, in correlation with clinical and radiological criteria. The test has a high sensitivity and specificity and a very good negative predictive value. We found the screening of GM ELISA to be a highly specific diagnostic tool in detecting IA manifested in patients undergoing HSCT.