The following statements are true

A. A distinguishing roentgenographic appearance of lung abscess, the air-fluid level can be seen only on roentgenograms obtained in the upright or lateral decubitus position.

B. The fungus ball characteristic of aspergillosis can be seen roentgenographically in either the upright or recumbent position.

D. The commonest fungal lung infection in the United States is due to Histoplasma capsulatum.

DISCUSSION: An air-fluid level distinguishes a lung abscess. While this can be seen easily in an upright or lateral decubitus roentgenogram, it cannot be seen when the patient is recumbent. The fungus ball characteristic of aspergillosis is identified by its crescent-shaped shadow on a roentgenogram. When the patient changes from an upright to recumbent position, the fungus ball may also change position in the cavity in the lung. Both actinomycosis and nocardiosis are bacterial infections and do not respond to antimycotic treatment. Actinomyces israelli is treated with penicillin and Nocardia asteroides is sensitive to trimethoprim-sulfamethoxazole. The most common fungal infection in North America is histoplasmosis. More than 30 million people have been infected, most of whom are asymptomatic.