INFLAMMATION OF THE PLEURA. 279 



diaphragm and the base of the lungs, and be very difficult of recog- 

 nition, and often remain quite unrecognizable. 



DIAGNOSIS. It is not always easy to distinguish a pleuritis with 

 abundant exudation from a pneumonia, and the following are the chief 

 points upon which we may rely for the purpose : 1. Pleurisy scarcely 

 ever begins with a single violent chill, while in pneumonia this is the 

 rule. 2. The course of a pleurisy is never so cyclic, nor is there that 

 sudden and complete change for the better, or crisis, which we observe 

 in pneumonia. 3. In pleurisy the sputa are indicative of catarrh or of 

 oedema, and sometimes contain streaks of blood ; but there never is 

 that peculiar tough expectoration, stained yellow or yellowish-red, by 

 intimate admixture of blood, which is pathognomonic of pneumonia. 

 4. The principal physical signs indicative of pleuritic exudation are, 

 dilatation of the thorax, effacement of the intercostal furrows, displace- 

 ment of the heart and liver, faintness or absence of pectoral fremitus, 

 absolute dulness upon percussion, feebleness or absence of the respi- 

 ratory murmur ; whereas, in pneumonic infiltration, the chest is not 

 enlarged, the intercostal spaces are not effaced, the heart and liver 

 retain then* situation, the pectoral fremitus is seldom enfeebled, and, 

 indeed, is often intensified, the dulness upon percussion is not so abso- 

 lute, and the respiratory murmur is almost always bronchial. 



Patients having pleuritic effusions in their right side are not unfre- 

 quently supposed to have disease of the liver, and when we have ascer- 

 tained by palpation that the liver reaches below the border of the ribs, 

 and fills up the right hypochondrium, it is important that we should 

 be able to tell whether the organ is enlarged or merely depressed. 

 The following are the points of distinction between the two con- 

 ditions : 1. The liver rarely pushes the diaphragm upward ; hence, 

 when the liver extends below the border of the ribs, and we at the 

 same time find a dulness in the thorax which reaches farther upward 

 than the normal hepatic dulness should do, we may reasonably infer 

 that there is an effusion in the pleura and that the liver is pressed 

 downward. 2. In the very rare instances in which, through enlarge- 

 ment of the liver (usually from an abscess, or a cyst of echinococcus), 

 the diaphragm is abnormally pressed upward, and made to project 

 into the cavity of the thorax, the dulness reaches farther up in the 

 front of the chest, while in nearly every case of pleuritic effusion the 

 opposite condition obtains. 3. When the liver is enlarged, its lower 

 border, and with it the line of percussive dulness, moves downward 

 upon inspiration and upward upon expiration. This does not take 

 place when there is large effusion in the pleural sac, as the diaphragm 

 is then depressed, and kept in a state of permanent expiratory exten- 

 sion. 4. The transition from the feeling of resistance, presented bv the 



