3. Cellular gliosis of deeper layers of cortex. Apparent increase in capillary supply, possibly relative to loss of neural elements.
Case 57. Neurosyphilis (“disseminated syphilitic encephalitis” of A. M. Barrett), fatal seven months from initial infection. (Photographs by A. M. Barrett.)
Dr. Barrett was able to find in the literature a case of Bechterew which histologically resembled his own case, but though in the instance reported by Bechterew the first symptoms developed within the year following infection, death did not occur until two years later.
In view of a total duration of symptoms clearly not over seven months, it is interesting to inquire how far microscopic brain changes could have proceeded. Neither calvarium nor dura mater showed changes. There was a slight haziness of the pia mater over the convexity, but the pia mater over the base (especially below the cisterna and from thence spreading out over the pons and into the fissure of Sylvius) was not only hazy but definitely thickened and hyperæmic. The thickening was most marked about the root of the right third nerve (corresponding with the eye findings in life). There was also a macroscopic thickening of the left Sylvian artery. Section of the brain showed nothing abnormal except a small area among the pyramidal fibres of the right side of the pons, where there was a single hemorrhagic area about 7 mm. in diameter around which there were small punctiform hemorrhages. (Compare twitchings of left leg and arm upon stimulation of left leg, and note also the muscular twitchings and slight spasticity of right leg and arm noted just before death.) This case was examined and reported upon in 1905. We learn from Dr. Barrett that a re-study of the case with modern methods has failed to demonstrate a spirochetosis.
The meninges show infiltration and destructive and proliferative changes of the blood vessels. Condensed extracts from Dr. Barrett’s full report follow:
There were local variations in the severity of the meningitis. The sulci showed the most marked infiltration. The slighter degrees of exudation were made up largely of lymphocytes with a few plasma cells, occasionally large mononuclear cells, and rarely a polymorphonuclear leukocyte. Where the exudation was more extensive, the large mononuclear cells became more common and the polymorphonuclear leukocytes increased in number. The large mononuclear cells were often phagocytic, containing from one to six leukocytes. The exudate was always most abundant about the blood vessels. The plasma cells were always most numerous in the adventitia of the veins, here greatly outnumbering the leukocytes. The polymorphonuclear leukocytes were relatively infrequent except where there were necrotic areas, which areas were usually continuous with an infiltration of a vessel wall.
As to vascular changes, the media was not often involved, nor was the adventitia so often affected as the intima. Such lesions as appeared in the intima and adventitia were infiltrative rather than proliferative. The elastica of the blood vessels proved to show but slight changes.
A characteristic change was the endarteritis,—of a focal nature with a few large mononuclear and lymphocytic cells pushing the intima inward at the edge of a lesion. In the more marked portion of the focal process, the thickness of the intima was greatly increased by proliferation. Great numbers of large mononuclear cells could be seen between the intima and the elastica. About these cells and interlacing among the other elements of the proliferating tissue was an excess of connective tissue fibres.
The meningeal veins were more often diseased than the arteries; there was adventitial infiltration with lymphoid and plasma cells; sometimes the vein walls had become necrotic and infiltrated with polymorphonuclear leukocytes.
It will be remembered that the left Sylvian artery was grossly thickened, and microscopic section of this vessel showed a partial thrombosis.