Objective: To determine whether quantification of specific antifungal antibody responses in serum can provide supplemental information for the diagnosis of Aspergillus fumigatus infections and the monitoring of antifungal treatment in patients after lung transplantation.
Design: Retrospective study.
Setting: Center for lung transplantation, University Hospital Groningen, the Netherlands.
Patients: 4 patients with proven A. fumigatus infections after lung transplantation and fatal outcome.
Measurements: The IgG antibody response specific for A. fumigatus antigens was measured by enzyme-linked immunosorbent assay and was compared with radiographic features, cytologic findings, microbiological cultures, and clinical diagnosis.
Results: Increasing IgG antibody responses specific for A. fumigatus antigens closely paralleled cytologic or microbiological identification of A. fumigatus from bronchoalveolar lavage fluid and decrease of lung function. Increasing specific IgG antibody responses were found to precede radiographic identification of lung cavitation by 1 to 2 weeks, precede the diagnosis of aspergillosis by 2 to 20 weeks, and detect fungal reinfection. In most cases, successful antifungal treatment decreased specific IgG antibody response. A decrease in specific IgG antibody response correlated with the inability to culture or identify A. fumigatus in bronchoalveolar lavage fluid and with radiographic and clinical improvement.
Conclusions: Specific IgG antibody responses in serum correlate with radiographic, cytologic, and microbiological findings and with the clinical diagnosis of A. fumigatus infections in patients who have had lung transplantation. Increased IgG antibody responses in serum may provide important information that is helpful in the diagnosis and early treatment of pulmonary fungal infections and in monitoring antifungal treatment.