- A number of methods are used to diagnose fungal pneumonia. Ones that are commonly used in clinical practice include radiographic imaging (chest X-rays and computed tomography (CT) scans), blood tests, and cultures taken from fluid from the lungs (broncho-alveolar lavage (BAL) fluid). Other new methods may improve the diagnosis of fungal pneumonias. These methods include tests that can detect DNA from the fungal germ in blood and BAL fluid of some patients with these infections.