Complications.—Inflammation of neighbouring tissues often complicates a case of pneumonia. In the child a certain amount of bronchitis is a com mon feature of the illness. In almost all cases we can detect some sonoro sibilant rhonchus not only in the affected lung but also on the opposite side of the chest. In many instances there is also some moist rhonchus. As a rule the amount of bronchitis is trilling, and the complication is rarely sufficiently marked to be a source of danger.
Plastic pleurisy may also accompany the pulmonary inflammation, and sometimes there is a moderate liquid effusion. The pleurisy is seldom of much moment, and absorption usually occurs rapidly when resolution of the inflammation has taken place. As has been before remarked, the per sistence of dulness over the seat of disease during convalescence is com monly due to the presence of a layer of lymph upon the pleural lining of the chest.
Pericarditis is sometimes induced by extension of the inflammation ; but this complication is less common in pneumonia than in the case of pleurisy. In the child the inflammation of the pericardium, when it occurs in the course of a croupous pneumonia, is usually plastic, and is but rarely accompanied by effusion. In regard to prognosis it is probably of small importance.
Jaundice is sometimes seen, and is usually mild. It is due to pressure upon the bile-ducts by hypermic portal vessels, the circulation through the liver being impeded owing to the condition of the lung. It may also arise from gastro-duodenal catarrh. If this be sufficiently intense to create an impediment to the introduction of nourishment, the consequences may be serious. Gastric or intestinal catarrh may be present without jaundice. Diarrhoea is a symptom not unfrequently seen at the begin ning of an attack of pneumonia. As a rule, the purging is not excessive, and ill consequences rarely follow from the intestinal derangement.
Diagnosis.—In a well-marked case of croupous pneumonia the diag nosis is not difficult. The sudden occurrence of high fever, headache, pain in the side, short hacking cough, perverted pulse-respiration ratio, and rapidly increasing muscular weakness is very suggestive of this disease. It is important to bear in mind the nervous symptoms which often accom pany the onset of the illness, or we may alarm ourselves with suspicions that an inflammatory head affection is about to manifest itself. But although a feverish child is often light-headed at night, and wanders somewhat in his talk, high fever with early and marked delirium is not a common occurrence; indeed, this combination breaking in upon a state of health, if combined with a short hacking cough, is almost peculiar to pneumonia.
If in addition, we notice that the pares dilate at each inspiration, and that the breathing is quickened out of proportion to the pulse, we are justified in entertaining the strongest suspicions that the attack is one of croupous inflammation of the lung.
In some cases cough is absent, or is so slight that it passes quite unno ticed, and the flares are motionless in inspiration. Still, the sudden occur rence of a high temperature, with pungent heat of skin, as estimated by the hand, combined with early delirium, should suggest the presence of pneumonia. In all such cases the chest should be minutely examined. for confirmatory evidence. It must be remembered that the physical signs are often slow to appear, and that forty-eight hours, or even three or four days, may pass without any consolidation of the lung being discovered. It must also be remembered that the severity of the symptoms is not in proportion to the extent of lung-tissue involved, and that after a violent onset the local. signs may be confined to a mere patch of solidification at any part of the pulmonary surface. We must not therefore, content ourselves with a cursory examination of the bases of the lungs. Careful attention must also be directed to the apices, and we must not forget to search the axillaa on either side for evidence of disease. In cases of pneumonic consoli dation the dulness is not complete, and is accompanied by little increase in resistance. Moreover, in the large majority of cases the signs are limited to one aspect of the chest. Sometimes a faint vibration of the chest-wall, inappreciable upon the healthy side, may be detected over the seat of disease when the child speaks or cries.
The combination of high fever, headache, and diarrhoea may be per plexing. If the patient be an infant, the symptoms may be ascribed to teething, and the condition of the lung may be overlooked. The nares, however, act, and the respiration, if counted, will be found to be hurried out of proportion to the pulse. If a physical examination be made, as it ought to be, a matter of routine, the nature of these cases will not escape recognition. In an older child the same combination of symptoms would suggest enteric fever. But the violent onset, the flushed cheeks, the active pares, the rapid breathing, the hacking cough, are very unlike the begin ning of enteric fever ; and if delirium come on, it begins very early (on the first or second day) in pneumonia, while in typhoid fever it is rarely seen before the end of the first week.