Clinically, this diagnosis may be extremely difficult to make, and transbronchial or open lung biopsy may be hazardous in immunosuppressed patients because of profound bone marrow suppression.

• （然而）临床上诊断极难确立，因为深度骨髓抑制导致的免疫抑制，使经支气管或开胸活检变得十分危险。