292 THE VITAMINES 



The most important changes in beriberi were noted in the periph- 

 eral nerves and muscles. In the peripheral nerves, no macroscopic 

 changes were apparent, aside from the occasional observation of 

 minute hemorrhages in the sheath or between the fibers. Micro- 

 scopically, however, all stages of degeneration are noted. The 

 changes begin with the nerve; the medulla becomes varicose, espe- 

 cially near the constrictions; it falls apart in clumps and masses and 

 finally in a granular detritus. The axis cylinder, on the contrary, 

 frequently remains intact for a long time, but in the end this too dis- 

 integrates. The Schwann's sheath then becomes a shapeless mass, 

 with increase of the nuclei. In fresh acute cases, the number of 

 degenerated fibers is very slight. At the nerve endings in the 

 muscles, only those nerve fibers leading to the degenerated muscle 

 fibers are swollen and granulated. This degenerative neuritis occurs 

 chiefly in the ulnar, radial and medial nerves in the legs and later in 

 the phrenic and vagus nerves. Balz (837) found the same to be true 

 of the kidney nerves. Most apparent, however, was the degeneration 

 of almost all of the spinal cord nerves. Balz (I.e. 887), as well as 

 Ellis (888), found changes in the sympathetic and especially in the 

 cardiac, pulmonary, splanchnic and solar plexi. Rumpf and Luce, 

 (889) found degenerative processes in the dorsal roots. In the brain 

 and spinal cord, as well as in other organs, there is venous stenosis 

 and edematous impregnation. Some investigators have found the 

 motor ganglia cells of the ventral horn atrophically vacuolized. The 

 nucleus lies often asymmetrically, pushed to one side by a large 

 vacuole. Rumpf and Luce found fresh parenchyma and diffused 

 medullary sheath degeneration in the white substance of the spinal 

 cord. The pathological-histological changes in the nervous system 

 will be further described under the subject of pellagra, accompanied 

 by numerous illustrations, for according to the view of an eminent 

 neuro-pathologist, Mott (890), these changes belong, in both diseases, 

 to the same type; however, it should not therefore be said that 

 both diseases must be etiologically related. 



The affected muscles show all signs of degeneration and atrophy. 

 The first signs of this consists of the dimming of the striations. Fre- 

 quently, the muscle fibers become waxy, homogeneous and fragile. 

 For the remaining pathological changes, we may refer to what has 

 been said under the subject of avian beriberi. 



