EFFECT OF DEFICIENCY IN MAN 



sheath is the most usual finding, but in some cases the axis cyHnder 

 itself is fragmented. Changes may also be seen in the posterior 

 ganglion and anterior horn cells. Degeneration is found as a constant 

 factor in all peripheral nerves ; it generally starts in the legs, spreading 

 to the arms later, and then to other parts of the body. The myelin of 

 the sheath is broken up into balls or threads and eventually disappears. 

 In this last event the axis cylinders appear to be coiled, and may be 

 fragmented and atrophied. Parallel with these nerve changes, hyper- 

 aesthesia and then anaesthesia occur in the legs, and the leg and thigh 

 muscles become atrophied, with loss of cross -striation and shrinkage of 

 the sarcoplasm. Later the hands and arms, and even other parts of 

 the body, become affected in the same way. These nerve and muscle 

 changes are, of course, not peculiar to beriberi, but occur in all forms 

 of polyneuritis. 



In cases where oedema occurs, it is first observed in the legs and 

 thighs, and may later spread to other parts of the body, oedema of 

 the lungs being a frequent symptom. At autopsy, serous fluid may 

 be found in the subcutaneous tissue, usually the pericardium, the 

 pleura and the peritoneum. The oedema is probably due to generalised 

 capillary dilatation with increased permeability to plasma, and may 

 disappear quite suddenly after a sudden diuresis. 



In Europe and the U.S.A., classical beriberi is rarely seen, and 

 vitamin B^ deficiency occurs in the form of polyneuritis induced by 

 special circumstances. Alcoholic polyneuritis ^ is a vitamin B^ 

 deficiency arising in chronic alcoholics whose high intake of calories 

 in the form of alcohol increases their vitamin B^ requirements. The 

 condition is often aggravated by the gastro-intestinal disturbances 

 that arise in such cases ; these lead to defective absorption of such 

 vitamin B^ as is taken in the form of food. Polyneuritis of pregnancy ^ 

 may arise through the increased metabolic requirements of the foetus, 

 and lack of the vitamin may be aggravated by loss of food in vomiting. 



Beriberi was encountered in Japanese prisoner-of-war camps 

 during the war of 1939-45.* It was characterised by anorexia, 

 nervous manifestations, tachycardia and arrhythmia. The symptoms 

 were cured by aneurine, but a vitamin B complex preparation was 

 even more effective. 



Other Conditions Associated with Vitamin Bi Deficiency 



Aneurine deficiency may also be associated with pregnancy accom- 

 panied by a poor diet, pregnancy anaemia, pernicious anaemia accom- 

 panied by myxoedema, steatorrhoea, idiopathic hypochromic anaemia , 

 scurvy, carcinoma and ulcer of the stomach, fatal pulmonary tuber- 

 culosis, anorexia nervosa and following gastrectomy,^ In some forms 



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