Fig. 87.-Posterior view. Skiagraph taken after death from general miliary tuberculosis complicating pulmonary phthisis. Extensive tuberculous infiltration with pleural thickening of left side. Heart small, obscured, pulled materially to left. This picture is of especial interest as showing well-defined miliary deposit in right lung, unobscured by thickened pleura.

Fig. 88. Posterior view. Pronounced fibrous tissue proliferation of right lung, producing marked displacement of heart to right. Slight destruction of pulmonary tissue, as shown by cavity, best marked between sixth and seventh ribs. Moderate infiltration at root of left lung. (This condition is more fully described in text, see p. 296.) Heart of small size.

Fig. 89. Posterior view. Thickening of mediastinal pleura, with heart dislocated upward. Slight infiltration in right upper lung. Two well-marked glands at root of right bronchus. This picture is of interest by virtue of anomalous shadows upon each side, incapable of interpretation by physical signs or by x-ray appearance. Heart of small size.

Fig. 90.-Anterior view. Large abscess in right lung, following pneumonia. Circumscribed shadow very closely simulating aneurysm, and blending with the shadow of the heart. Condition confirmed by autopsy (courtesy of Dr. Sewall).

CHAPTER XLI

DIFFERENTIAL DIAGNOSIS

THE clinical manifestations of a few chronic non-tuberculous pulmonary conditions closely simulate those of consumption. While a provisional diagnosis may be made from the history, occupation, clinical course, and physical signs, in many instances, a definite differentiation from pulmonary tuberculosis is rendered possible only by exhaustive sputum examinations, and, in a few cases, through recourse to the newer methods of diagnosis. Occasionally even the presence of bacilli does not afford accurate information as to the precise nature of the pathologic change. This is particularly true of the so-called "miner's phthisis," difficult of disassociation from consumption, yet differing widely in the character of the morbid conditions. The appearance of bacilli only after long-continued observation does not. justify the assumption of tuberculosis as a factor of etiologic importance. The terminal infection is merely ingrafted upon a soil previously made receptive by virtue of marked pathologic change. Miner's phthisis consists of an interactive combination of chronic bronchitis, emphysema, and pneumonokoniosis in connection with frequent bronchiectases and circulatory disturbances. The symptoms and general course are described elsewhere. In this connection it is sufficient to state that the clinical manifestations are very suggestive of tuberculosis, especially the cough, expectoration, dyspnea, and the occasional hemorrhages. There is rarely, however, any elevation of temperature. The cyanosis is quite disproportionate to the physical evidences of pulmonary involvement. The dyspnea rapidly increases until it is noticeable even upon the slightest exertion. The cough is usually paroxysmal, and the sputum frothy and light. The physical signs which are described in connection with pneumonokoniosis do not differ materially from those displayed by many cases of pulmonary tuberculosis. While often there are bilateral evidences of catarrhal involvement and emphysema, physical examination sometimes discloses signs of unilateral consolidation, with circumscribed areas of moisture and not infrequently pulmonary cavities. The history, occupation, absence of fever, disproportionate dyspnea, and cyanosis, the paroxysmal character of the cough, the frequent separation of the sputum into distinct layers, together with the bilateral signs of catarrhal disturbance and the coëxisting emphysema, with continued negative bacteriologic findings, suggest the essential non-tuberculous character of the condition, despite the occurrence of hemorrhage and the occasional unilateral involvement. There can be but little excuse for confounding pulmonary tuberculosis with acute or chronic bronchitis, bronchiectasis, uncomplicated emphysema, or chronic interstitial pneumonia. The fact, however, that this group of conditions in connection with varying degrees of pneumonokoniosis as frequently observed in mining regions, with or without cavity formation, constitutes a very considerable proportion of all cases of chronic non-tuberculous pulmonary affections, affords ample opportunity for errors in diagnosis. This grouping of conditions is more or less frequent in parts of Colorado, and is often confused with tuberculosis.