890 GAEL VOEGTLIN" 



polyneuritis was also observed in rats by various authors, and Voegtlin 

 and Lake (1919) have shown that it can be produced with great reg- 

 ularity, and with very striking symptoms, in cats fed on beef which is 

 autoclaved for three hours after a sufficient amount of sodium carbonate 

 has been added to render the mixture alkaline to litmus. The final link 

 in the chain of evidence was furnished by Funk, 1 who isolated from rice 

 polishings, and certain other foods which were known to possess pre- 

 ventive properties, a substance which was exceedingly efficient in relieving 

 the symptoms of polyneuritic birds. The probable identity of this sub- 

 stance with so-called water-soluble B was finally established by McCollum 

 and Kennedy (1916) and Dnimmond(a) (1917). 



Some writers have regarded polyneuritis gallinarum as a condition 

 resulting from starvation. To this may be replied that polyneuritis ap- 

 pears even in animals under forced feeding (Chamberlain, Bloombergh 

 and Kilbourne, 1911). 



Pathology. The principal characteristics of the pathological anatomy 

 of this disease include: (1) degenerative changes in the nervous system; 

 (2) changes in the heart; and (3) anasarca and effusions in various parts 

 of the body. In acute cases, the body may be in a fair state of nutrition, 

 in chronic cases extreme emaciation is found. In acute cases there is also 

 some edema, which at times may be excessive, involving the legs and face. 

 The lungs may be congested and edematous. The right heart is always 

 greatly dilated in acute cases and often hypertrophied in chronic cases. 

 Microscopically the myocardium shows more or less loss of striation of its 

 fibers, which are vacuolated. There is an increase in- pericardial fluid. 

 The mucosa of the stomach and upper intestine is hyperemic and more 

 or less injected. The liver and the tubular epithelium of the kidney show 

 cloudy swelling and fatty degeneration. The fibers of the skeletal muscles 

 have an indistinct outline, and the sarcoplasm is swollen or separated from 

 the sarcolemma. Baelz (1882) was the first to call attention to the exist- 

 ence of a peripheral neuritis in beriberi. This was confirmed by Scheube 

 (1884) and others. The peripheral nerves show a varying grade of 

 hyaline degeneration. Kagoshima (1918) observed atrophy of the optic 

 nerve in four out of 50 autopsies. Diirk (1908) and Wright (1905) de- 

 scribe the occurrence of degenerative changes in the spinal cord. The 

 meninges and brain may be hyperemic, and the fluid in the ventricles is 

 often found increased. Acute degeneration of the vagal ganglia at the 

 base of the fourth ventricle has been observed. Eecently Shimbo (1918) 

 examined the adrenals in 19 cases of beriberi and found hyperemia and 

 hypertrophy of the cortex without degeneration; the medulla was also 

 hypertrophied with marked round-celled infiltration around the vessels. 

 According to Ono (1916) the epinephrin content of the adrenals is 

 increased. 



1 See chapter on metabolism of vitamins. 



