Invasive pulmonary aspergillosis following bone marrow transplantation: risk factors and diagnostic aspect

To describe the clinical features and diagnostic aspects of invasive pulmonary aspergillosis (IPA) following bone marrow transplantation (BMT).

Retrospective review of the medical records of all BMT recipients in whom Aspergillus spp. were isolated from the lower respiratory tract. The diagnosis of IPA was definite when the fungus was demonstrated by histological examination or culture of lung tissue obtained by biopsy or autopsy. The diagnosis was probable when Aspergillus spp. were isolated by culture of BAL or sputum, with compatible clinical and radiologic picture.

There were 27 patients with IPA post-BMT (81% allo versus 19% auto). The diagnosis was made median of 20-week posttransplanttation: 67% had GVHD, 59% were on immunosuppressive therapy and 89% were on corticosteroids. Only 11% had severe neutropenia (ANC < 500). The clinical symptoms were nonspecific, and radiologically the commonest manifestations were nodules with or without cavitation 34%. The diagnosis of IPA was definite in 11 patients (41%): 6 by open lung biopsy, 1 by CT-guided biopsy, 1 by BAL and brain biopsy and 3 by autopsy. The diagnosis was probable in 16 (59%): 6 by BAL, 7 by sputum culture and 3 both. Aspergillus spp. were recovered from 10/17 (59%) patients who had BAL and 10/15 (67%) who had sputum culture. 25 patients were treated with antifungal agents (19 amphtericin B alone, 4 amphotericin B and itraconacole, 2 variconazole). 16/27 (59%) died a median of 15.5 days after the diagnosis of IPA. 5 had documented evidence of disseminated disease, most commonly to brain.

IPA is an important problem following BMT. Allogeneric transplant, GVHD, immuno-suppressive and corticosteroid therapy are the main risk factors. BAL and sputum examination are helpful in making the diagnosis in the appropriate clinical setting. Although the mortality associated with IPA remains high, however it is lower than what was previously reported.