The characteristic physical signs noted in all textbooks are described in detail by Kraepelin[175] as common to all of the clinical forms of the disease. The inequality, irregularity and immobility of the pupils, the speech defect, difficulty in writing, tremor of the lips, facial muscles and tongue, the marked changes in both superficial and deep reflexes, the alterations in the gait, the muscular incoordination, the presence of the Babinski reflex or ankle clonus, the sensory, motor, vasomotor and trophic disturbances constitute a combination of physical signs which is to be found practically nowhere else within the domain of psychiatry. The seizures, either epileptiform, apoplectiform or resembling syncopes, are almost pathognomonic when taken into consideration with the physical signs alone.
The pressure of the cerebrospinal fluid is from three to five times as great as in normal individuals. The albumen content of the fluid is increased about six times (Kraepelin). The increase in the globulin content has been very frequently referred to in the literature of general paresis. Kraepelin states that it also occurs in tabes, syphilis, brain abscess, occasional cases of extra medullary tumors, multiple sclerosis and in some infectious diseases. He attaches a great deal of importance to the increase in the cellular elements of the spinal fluid. "Cases with repeated normal findings are so rare that the correctness of the diagnosis may be justly doubted." The Wassermann findings no longer require comment. The colloidal gold test of Lange is equally well known. Nowhere else in psychiatric procedure does the laboratory render such valuable diagnostic assistance as is the rule in cases of general paresis. A positive Wassermann reaction in the spinal fluid, the presence of an increase in the albumen and globulin content, with a marked lymphocytosis in the cerebrospinal fluid and a positive gold test, is quite sufficient evidence on which to base a definite diagnosis. The results of an examination of the spinal fluid for diagnostic purposes at the time of autopsy are highly unreliable. An increase in the cell count, which may be misleading, is found in the spinal fluid of non-paretics in all cases after death. The number of cells depends entirely on the time of examination. It is not at all unusual to find from one to three hundred per cubic millimeter when a count is made from twenty-four to forty-eight hours after the death of the patient.[176] Another interesting fact is that the presence of sugar always shown by Fehling's solution during life cannot be demonstrated postmortem, at least after the lapse of a few hours.[177] The significance of this change is not clear. Nor is the increase in the globulin content of the spinal fluid, when taken alone, pathognomonic of either general paresis or syphilis, as was pointed out in 1909.[178] One of the most elaborate studies ever made of the spinal fluid, that of F. W. Mott, shows that this increase is due to degenerative processes of the nervous system which may be due to a variety of causes.[179]