Typhoid fever in children ;nay begin with and have throughout its course a high temperature; so that for days it will be impossible to ar rive at a definite conclusion until, on the one side, pulmonary symptoms, and, on the other side, enlargement of the spleen, roseola, diazo- and Widal-reaction, become prominent. Until bronchial signs decide in their favor, grippe and influenza with high fever may for days raise a suspicion of croupous pneumonia, if the catarrhal conditions of the upper air-passages and the conjunctiva are not pronounced,. and if a somewhat dyspnceic breathing as the result of swelling of the bronchial mucous membrane be present. Likewise, a simple bronchitis with high fever does not permit a differentiation from pneumonia during the first few days.
Whenever positive physical signs are found in the lungs, a differen tial diagnosis of bronchopneumonia, pleuritis, and acute tuberculosis of the lungs, is to be made.
The differentiation from bronchopneumonia, which has already been mentioned on page 357, cam usually be made; although since the local symptoms are not always sufficient for this purpose, the develop ment, course, and temperature curve must be considered. Still, there are cases—especially in measles and grippe—in which these two types cannot always be separated clinically. Even the anatomist is sometinies in doubt how he should classify a pneumonia which he has found to be present. In exceptional eases, bronchopneumonia and croupous pneumonia may co-exist.
We are frequently confronted at the bedside by- the question whether a croupous pneumonia or a pleurisy with effusion is present, when dul ness, bronchial breathing without rales, or with scanty fine roles, appear in the reffion of the lower and posterior portions of a lung: in connec tion with which the local physical signs, course, and temperature, are to be taken into consideration. In croupous pneumonia, dulness devel ops rapidly and almost simultaneously in its entire extent, and is at times more marked above than below. Almost always Traube's space remains free. In addition, the dulness disappears in a few days after the decline in the temperature. The sensation of resistance is not marked. In pleurisy, the dulness is greater and the sensation of resis tance is more marked than in pneumonia. The dulness is most marked behind and below, and gradually rises above and to the side. If it is
present behind about the middle of the scapula. dulness is also found anteriorly. In large effusions the neighboring organs (heart and liver) are displaced. If the dulness involves the entire side behind and in front we are dealing with a pleurisy in the majority of cases. The dul ness gradually diminishes from above downwards. In croupous pneu monia loud bronchial breathing is most plainly heard where the dulness is most marked. Bronchophony is very marked. In pleurisy, bronchial breathing and bronchophony are less pronounced and softer, and are most marked at the upper border of the dulness. On the other hand, bronchial breathing is heard almost everywhere in extensive and recent effusions. In these cases the respiratory murmur is not abolished as in adults. Egophony points to plemisy. Increased vocal fremitus points directly to pneumonia: whereas, on the other hand, the fremitus often cannot be determined and is not infrequently diminished as a result of occlusion of the bronchi. In pneumonia, the re.spiratory movements of the affected side are only slightly limited; whereas, in pleurisy they are very markedly so, and in eases of extensive pleurisy the affected side is noticeably expanded even to the eye. Croupous pneumonia is charac terized by a high, and after about 5-9 days, critical decline of tempera ture. Pleurisy, if it is not purulent in character, rarely- causes a high temperature, at least, perhaps, only during the first few days. It then soon shows marked remissions. gradually becoming normal in from two to four weeks. A pleuritic effusion, developing during the course of a pneumonia of an upper lobe and accumulating below, may readily simulate a fresh pneumonia.
Pleurisy with effusion may frequently occur in combination, or as a sequela of croupous pneumonia. In these cases, the temperature rises during the last days of a pneumonia, is prolonged or shows an imperfect decline by lysis, and in cases of subsequent increase often points to a purulent character of the effusion. The pulmonary dulness is increased by the simultaneous development of an effusion, the resistance is in creased, and the fremitus is diminished or abolished. On the other hand, bronchial breathing and bronchophony are usually increased and not diniinished as one would readily suppose. Displacements of neighboring organs occur.