Respiration, in the moderately advanced cases, is usually not much im paired during rest. By breathing deeper and more frequently, the patient compensates for the quantity of oxygen lost by destruction of the affected portions of the lungs ; and, moreover, he gradually becomes accustomed to the disturbances so long as they are not too violent. On bodily exertion, however, changes in respiration are frequent ; and toward the end of life difficulty in breathing is one of the most distressing symptoms of the disease.
The colour of the patient's skin is usually pale ; and if extensive changes have taken place in the lungs, it has a bluish tinge. If fever be present, the face—often only a part of the cheeks—becomes markedly flushed. In many cases bright or brownish-yellow glistening spots develop on the fore head and on the upper parts of the cheeks ; in other cases such spots appear on the chest, hack, and abdomen. The tendency to profuse perspiration is very marked, being brought on even by slight bodily exertion or mental excitement. Night-sweats, which most frequently occur about midnight or during the early morning hours, are particularly annoying, and require treatment.
Only a few cases of pulmonary tuberculosis run their course entirely without fever. Moderate fever is present even during periods of comparative \ye] 1-being. In the morning and during the clay the temperature may be normal, but toward evening it usually rises to we or 'of' F. (so-called hectic fever). High fever, especially in the evening, occurs in acute tuberculosis. The fever is due to the presence of secondary pyogenic infections. These are also the most prominent causes of chilliness, heat, perspiration, and head ache. The course of the fever furnishes an essential criterion by which the physician may judge of the course of the disease.
The progress of consumption is marked by a gradual loss of strength and by constantly increasing emaciation. This progressive emaciation affects the adipose tissue as well as the muscular tissue. The skin may become so emaciated as to be almost as thin as paper when raised in folds ; and toward the end of the disease the various bones of the body become so distinctly visible under the skin that it appears as if nothing but the skeleton was left. During periods which are free from fever, the weight of the body may increase considerably, especially by the accumulation of fat. A contrast to the often
extensive changes in the lungs is seen in the mental alertness, liveliness, and hopefulness of the patients, which are often preserved until the end.
The complicating disease of pulmonary tuberculosis are quite manifold. The pleura often becomes affected, either by a dry or by a moist inflamma tion. Tuberculous infection of the throat may develop, causing pain on swallowing, hoarseness, and even loss of voice. Involvement of the intestine may cause refractory diarrhoea. Although tuberculous changes in the wall of the stomach are very rare, disturbances of digestion are by no means uncommon. The appetite is often impaired, even in the beginning of the disease ; and the patient often shows aversion toward the most important foodstuffs, such as meat, eggs, and milk, even when no fever is present.
To establish a diagnosis of pulmonary tuberculosis requires not only an exhaustive and careful examination of the patient's lungs and of the sputum, but of the entire body as well. If tubercle-bacilli be found in the sputum, tuberculosis is unquestionably present ; but, on the other hand, this disease must not at once be excluded, even when repeated examinations have failed to demonstrate the presence of bacilli. A very material aid in establishing a diagnosis is afforded by the use of the tuberculine test, which consists in injecting very small quantities of Koch's tuberculine under the patient's skin. If the patient shows a reaction to the tuberculine—that is, if he manifests a peculiar rise of the body temperature and disturbances of the general health—it may almost with certainty be assumed that tuberculous changes are present. In most cases, however, the physician may arrive at a decision without resorting to this test ; namely, by a careful examination of the lungs, and by a simultaneous consideration of the symptoms present. In some cases, however, this requires some time of observation.
The changes that take place in the lungs in the course of pulmonary tuber culosis cannot be described minutely in this place. Only those which it is necessary to know in order to get a general understanding of the disease will be mentioned.