Invasive Pulmonary Aspergillosis in Patients with Hematological Diseases and Hematopoietic Cell Transplantation

Invasive pulmonary aspergillosis (IPA) is an important infection in patients with hematological diseases, the non-malignancy condition aplastic anemia, and recipients of hematopoietic cell transplant (HCT). This is an exogenously acquired inhaled infection. HCT recipients have a risk of developing IPA of upward of 15% during and after the transplant, so this chapter emphasizes prevention. Prevention against IPA requires minimization of exposure to airborne spores when inpatient, as well as pharmacologic prophylaxis during the periods of highest risk. High-efficiency particulate air (HEPA) filtration is the gold standard method for the reduction of exposure to airborne spores among hospitalized patients. HEPA filtration can be augmented with portable laminar air flow units if there is construction or renovation in the patient treatment area. When systemic pharmacologic antifungal prophylaxis is used, the agent should cover molds well with minimal or manageable toxicities, such as triazole or echinocandin agents. Triazoles should not be used during cyclophosphamide therapy. When cancer patients and HCT recipients have too much nausea and mucositis to be able to tolerate an oral agent, an intravenous agent may be preferred. For continuous antifungal prophylaxis of many months duration, the at-risk patient may require a regimen that contains periods with intravenous agents and periods with oral agents. The sequential use of different antifungal agents may be needed to provide prophylaxis during the entire at-risk period. The diagnostic workup of an IPA infection is discussed in Chaps. 5 (radiology), 6 (biomarkers), and 7 (bronchoscopy with or without lung biopsy). Antifungal agents used for treatment are discussed in Chap. 8.