640 Acute Xoii-purulent Encephalitis. 



filtrations, the cells being round and Marsehalko 's plasma cells. In one case there 

 was edema of the neighboring tissue. In the hemorrhagic form there was a very 

 small infiltration of leucocytes, but in the perivascular spaces red blood corpuscles 

 were found in large masses and at greater distances from the vessels there were 

 red corpuscles either scattered aliout or arranged in rows. The endothelial cells 

 had proliferated and were enlarged, the lumen of the vessel being reduced. The 

 true nerve tissue in the neighborhood of the small centers showed very little alter- 

 ation (destruction of the medullary sheath, swelling of the axis cylinders, and at 

 places destruction of the chromatin bodies of the nerve cells), while the larger 

 centers were composed of softened masses. Degeneration of the medullary sheaths 

 could be followed in both forms of lesion. Not rarely inflammatory lesions were 

 found in the pia mater. 



In a portion of cases there was in addition to inflammation 

 of the brain a similar disease of the spinal cord. 



Symptoms. The symptoms of encephalitis due to any gen- 

 eral disease, such as influenza and distemper, are sometimes ob- 

 scured by those of the primary disease and so may remain quite 

 unrecognized. But in any case of this kind the attention of the 

 observer will be directed to some organic disease of the brain, 

 if by no other symptom, by the pronounced dullness in com- 

 parison with the severity of the primary disease. 



In the majority of cases the sjanptoms of brain trouble are 

 very striking. In cases where the inflammatory processes de- 

 velop rapidly or where the inflammation extends, general sjnnp- 

 toms of cerebral disturbance are never absent ; these, as a rule, 

 when there is rapid extension, appear suddenly, are very severe, 

 and are ushered in by somewhat severe hemorrhages. They 

 closely correspond with the other acute diseases of the brain; 

 rapidly progressive disturbance of consciousness is a prominent 

 symptom except in cases in which the disease sets in suddenly 

 owing to hemorrhage occurring at the outset. The animals ap- 

 pear dull and listless and are easily fatigued. They are indif- 

 ferent to their surroundings and stand with their heads dropped 

 or supported upon some object; appetite is greatly decreased 

 or quite absent, and they stand for a long time with half-closed 

 eyes, and their limbs in unusual positions. Occasionally they 

 lose their balance. As a result of this sleepy condition sensi- 

 bility is decreased. A gradual progression of these s^aiiptoms 

 leads, as a rule, within a short time to a condition of semi-con- 

 sciousness or even coma. 



In horses, and more rarely in other animals, the dullness is 

 followed by symptoms of excitement, which may be either very 

 slight or may amount to actual mania. This is especially so in 

 a case of hemorrhagic inflammation in the neighborhood of the 

 ventricles of the brain in a horse described by Dexler. After 

 the period of excitement the dullness is, as a rule, still more 

 marked. Occasionally in cattle there are similar symptoms of 

 excitement, but in the other species, and particularly in dogs, 

 no other symptoms are observed save pronounced restlessness. 



Spasms are often observed involving either individual mus- 

 cles or whole groups of muscles, or they may involve all the 

 voluntary muscles in paroxysms and possibly during the whole 



