A distinction between the catarrhal and tubercular forms of phthisis is readily made by comparing in each case the local signs with the general symptoms of the disease. Catarrhal phthisis, even when it begins at the apex by slow extension of the catarrhal process to the pulmonary alveoli, produces comparatively little impairment of the general nutrition of the body. The patient coughs and is a little feverish at night ; but his appe tite is usually good ; his strength is little impaired ; and he retains a fair amount of flesh. Even when the progress of the disease has led to exten sive consolidation of the lung, the marked contrast between the mildness of the general symptoms and the severity of the local signs discovered by physical examination, is sufficient to reveal the nature of the pulmonary mischief. In chronic tubercular phthisis the general symptoms are severe from the first. The child is pale and thin, feverish and languid, for some time before he is noticed to cough ; and it is still some time longer before examination of the chest discovers any positive indication that the lungs are the seat of pathological change. Moreover in catarrhal phthisis, until softening begins in the deposit, the disease is confined to. one lung. In tubercular phthisis the physical signs, when they do present themselves, are discovered at both apices.
On account of the frequency with which secondary attacks of sub-acute catarrhal pneumonia complicate cases of old consolidation, dilated bronchi are often present. These give rise to all the signs characteristic of excava tion ; and it is very important to satisfy ourselves as to the nature of the pathological condition. Dilated bronchi are most common in the child at the base of the lung, while cavities are more frequently seated nearer to the apex. Therefore the situation of the signs at the base, although by no means conclusive evidence, points rather to bronchiectasis than to a vomica. Again, the general symptoms are of great importance. Dilated bronchi, unless occurring as a chronic condition in a case of fibroid induration of the lung, are met with towards the end of an attack of broncho-pneumonia. If then we find that, with the physical signs of a pulmonary cavity, the general condition of the child is improving ; that the temperature shows signs of falling ; the appetite improves, and the flesh and strength begin to return, the evidence is strong that the signs are not the consequence of ulcerative destruction of lung. Moreover, much assistance is to be de rived from a microscopical examination of the sputum, where this can be obtained. In pulmonary ulceration areolar fibres of yellow elastic tissue will be seen in the inuco-pus vomited or expectorated ; in cases of bron chiectasis these will be absent. Lastly the progress of the signs will furnish corroborative evidence. Cavities tend to grow larger, dilated bronchi to contract. If, therefore, while the general symptoms remain stationary, the
area over which the cavernous signs are heard is found to extend itself, we cannot but conclude that disorganisation of lung is advancing ; while if, with general improvement, the local signs diminish in intensity, our opinion that these are due to dilatation of bronchi receives additional confirmation.
The distinction between pulmonary phthisis and fibroid induration of the lung is considered elsewhere (see page 478).
Empyema is often confounded with phthisis ; and there is no doubt that the general appearance of a child the subject of old-standing purulent effusion is very like that of a consumptive patient. There may be the same hectic, the same emaciation, and the same weakness. In each case the child is irritable and restless with a hacking cough, some shortness of breath, a poor appetite, and a feeble digestion. On examination of the chest in each case we find dulness, often extensive, with perhaps loud cavernous breathing. But the history of the illness is very different in the two diseases. In pleurisy it begins with pain in the side followed after an interval by cough ; the dulness is complete with extreme sense of re sistance ; it occupies both the front and back of the chest, unless the empyema be loculated ; and reaches down to the extreme base. Moreover, the disease is strictly limited to one lung, the other being healthy ; and sighs of pressure are noticed ; the affected side is expanded ; the inter costal spaces are less hollowed ; and the heart's apex is displaced. On the other hand, in a case of pulmonary phthisis sufficiently extensive to simulate a pleuritic effusion, the opposite lung will certainly show signs of disease. There will be no displacement of the heart or bulging of the side ; the dulness will not be complete ; the resistance to percussion will not be greatly exaggerated, if no great excess of fibroid tissue is present ; and the breath-sounds will be accompanied by a large-sized metallic gurgling rhonchus. In either case the vocal resonance will probably be bronchophonic ; but in empyema it often has an Lcgophonic quality.
Catarrhal phthisis in the young subject is very liable to be complicated by tuberculosis as a result of infection of the system by softening cheesy matter. The occurrence of tuberculosis is sometimes indicated by a rise of temperature and an increase in the rapidity of the breathing without any extension of the physical signs. Great irritability of the stomach and bowels is often induced ; the child vomits repeatedly, and the bowels are relaxed. Usually in these cases signs of intracranial irritation become quickly manifested ; and convulsions occur followed by squinting, ptosis, rigidity of joints, and other well-known signs of tubercular meningitis.