Pulmonary imaging and function in the common cold

The common cold is generally considered to be an upper respiratory tract in fection. We studied the lower respiratory tract in 76 otherwise healthy you ng adults with the common cold. Viral infection was diagnosed in 56 (74%) o f the 76 subjects. Rhinovirus was detected in 42 (55%) subjects. Chest radi ography (CR) and high-resolution computerized tomography (HRCT) were carrie d out in 40 subjects on day 7, and pulmonary function testing with bronchod ilator challenge was carried out in 36 patients on days 7 and 21 of the stu dy. Clinical examinations were carried out on days 1, 7 and 21. The subject s recorded their symptoms on a diary card for 20 d. The mean duration of co ugh was 8.4 (SD 6.5) d and that of sputum production 5.9 (SD 6.4) d. No abn ormal findings were detected in the lungs on auscultation. CR and HRCT show ed no pulmonary changes associated with the common cold. No clinically rema rkable increases were seen in peak expiratory flow, forced expiration volum e in I s or forced vital capacity after bronchodilator challenge on either days 7 or 21. All patients made a clinical recovery without antimicrobial t herapy within 21 d. We conclude that the common cold in young otherwise hea lthy adults is an upper respiratory tract infection and that clinically imp ortant abnormalities in the lower respiratory tract are rare.