Invasive pulmonary aspergillosis: effects of early resection in a neutropenic rat model.

OBJECTIVE: Invasive pulmonary aspergillosis is frequent in neutropenic patients. Usually localized in the beginning, the disease spreads and mortality is high despite antifungal treatment. The role of early adjuvant surgery is not clear. Surgery may help to confirm fungal disease, may control fungal disease locally and may prevent systemic spreading. This study examines effects of early resection on survival and dissemination in a rat model of localized invasive pulmonary aspergillosis. METHODS: Forty persistently neutropenic male albino rats were challenged with standardized conidial aspergillus inoculum injected into peripheral lung tissue of the right upper lobe under direct vision. Animals were divided into four groups. Twenty animals were treated with amphotericin B at 1 mg/kg per day beginning 48 h after inoculation, 20 animals were left untreated. In each group half the animals underwent early resection of localized invasive aspergillosis by lobectomy. Animals were checked daily and mortality was recorded up to 28 days after which surviving animals were sacrificed. RESULTS: Significantly higher survival was observed in resected animals in the non-Am B groups (survival: 10 +/- 19% without early resection and 50 +/- 32% with early resection; P = 0.044). However, early resection did not lead to improved survival in animals treated with amphotericin B (survival 70 +/- 29% without early resection and 50 +/- 32% with early resection; P = 0.316). CONCLUSIONS: In this rat model of localized invasive pulmonary aspergillosis effects of early resection on survival could be demonstrated only in animals not receiving amphotericin B treatment.