Objective: Two diagnostic tests, ELISA for circulating galactomannan and PCR, were compared for diagnosing and monitoring invasive pulmonary aspergillosis in an animal model.Methods: In a model of invasive left-sided pulmonary aspergillosis in persistently neutropenic rats, dissection was performed on day 1, day 3, day 5 and day 7 (n=20 each day) after inoculation. Within blood samples, PCR as well as ELISA was performed. Fungal dissemination to other organs (right lung, liver, kidney, brain) was determined. In addition, 20 rats were serially sampled, 10 for each test.Results: PCR was positive in 0% of the rats on day 1, 20% on day 3, 25% on day 5 and 40% on day 7. ELISA was positive in 0% on day 1, 100% on day 3, 90% on day 5 and 95% on day 7. The combinations positive ELISA-negative PCR as well as negative ELISA-positive PCR were observed. Positive ELISA or PCR was not associated with fungal dissemination. Serial testing showed consistently increasing concentrations of galactomannan during the course of disease. In contrast, positive PCR could be followed by negative results.Conclusions: ELISA was more sensitive than PCR, especially in the early phase of the disease. Concentrations of galactomannan increased significantly with the increase of severity of disease, in contrast to PCP.
Full conference title:
9th European Congress of Clinical Microbiology and Infectious Diseases
- ECCMID 9th (1999)