Normal Chest Roentgenograms in Chronic Diffuse Infiltrative Lung Disease

Abstract

We undertook this study to determine the prevalence of normal roentgenograms in chronic diffuse infiltrative lung diseases. Of 458 patients with such disorders histologically confirmed, 44, or 9.6 per cent, had normal pre-biopsy films. In this group with normal x-ray films, desquamative interstitial pneumonia, sarcoidosis and allergic alveolitis were the most frequent diagnoses. Dyspnea was the principal complaint, and fine rales were common. The vital capacity was reduced in 57 per cent, and the single-breath diffusing capacity in 71 per cent. In half, histological changes and functional impairment were moderately severe. Films may be normal in such cases because isolated foci are too small or too few, because diffuse interstitial or intra-alveolar disease may cast no discrete shadows or because the lesions primarily affect airways or blood vessels. Patients with normal chest roentgenograms and normal mechanics of breathing but with impaired gas exchange should have lung biopsy for early diagnosis and therapy.

Summer-type hypersensitivity pneumonitis: comparison of high-resolution CT and plain radiographic findings.

“…Reports of the distribution of pulmonary shadowing in farmer's lung are inconsistent [22]. In hypersensitivity pneumonitis, chest radiographic findings may be normal [23][24][25].…”

Interobserver Variations in Diagnosing Asbestosis According to the ILO Classification

“…He also believes that experts agree routinely about the interpretation of normal fi lms. However, Epler et al (20) reported that in a number of subjects with apparently normal fi lms, subsequent biopsies confi rmed chronic diffuse infi ltrative lung disease. Frumkin et al (21) also found a considerable inter-reader variability.…”

Diagnostic approach to interstitial lung disease

“…HRCT may identify diffuse parenchymal disease undetectable on plain x-ray. In one large series, approximately 10 % of patients with biopsy-proven diffuse lung disease had an apparently normal chest radiograph [21]. In some cases, appearances on HRCT are pathognomonic of a histo-specific diagnosis: typical HRCT patterns are listed in Table 2.…”