288 PYRIDOXINE AND RELATED COMPOUNDS 



nant women who had been treated for nausea and vomiting with pyridoxine, 

 the index was from to 0.58. 



This tryptophan load test should be repeated on a larger number of cases 

 of pregnancy and extended to other conditions, such as radiation sickness, 

 in which clinical observations seem to support the therapeutic efficacy of 

 pyridoxine. Until such more exact biochemical metabolic data become 

 available, no definite conclusions may be drawn as to the therapeutic value 

 of pyridoxine in these and similar clinical conditions. 



All the above described more or less circumstantial or at least artificially 

 produced evidence in favor of clinical vitamin Be deficiency and, there- 

 fore, in support of vitamin Be reciuirement for man, has received most re- 

 cently striking and unequivocal support in direct clinical observations. 



Hunt et aL^"" observed a young infant in a very serious convulsive state 

 lasting for several weeks after birth. This infant responded dramatically to 

 injection of pyridoxine or to larger amounts of pyridoxin e-HCl given daily 

 by mouth (1 to 2 mg.). The basic, puzzling, and unexplained metaboUc 

 defect in this infant has been Be dependency on a higher level of dietary 

 requirement. 



Even more convincing for the essential nature of vitamin Be in human 

 dietary was the widespread occurrence of nervous irritability and convul- 

 sive seizures in young infants in the age period of 6 weeks to 6 months 

 receiving a proprietary liquid, canned (autoclaved) milk formula. This 

 formula represents an approximately one-third diluted cow's milk "with 

 added lactose and fat. Thus, the original vitamin Be content of this formula 

 is also about one-third of that of undiluted cow's milk. During autoclaving, 

 the content of the thermolabile, natural vitamin Be in this preparation was 

 further reduced by two-thirds of the original amount and reached a level 

 of about 60 7 per liter, far below the level of vitamin Be in human milk 

 (100 to 120 7). In contrast, the same, but spray-dried, powdered, and not 

 autoclaved, formula showed no appreciable destruction of vitamin Be , and 

 the vitamin Be level remained around 180 7 per hter. No cases of nervous 

 irritability or convulsions were seen in infants receiving the spray-dried 

 formula with its higher vitamin Be content. 



The relation of vitamin Be to this nutritionally induced convulsive dis- 

 order is best illustrated by the observation of Coursin^"^ in a 23^-month- 

 old infant. This infant received the proprietary Hquid formula from birth 

 without supplements. 



"At 4 weeks of age, the baby was noted to be irritable aud to have supposed colic 

 pains with tossing of its head and stiffening of the entire body. Progressive changes 

 with staring episodes and generalized seizures were noted.'-* At the age of 2)'^ months, 



2o« A. D. Hunt, Jr., J. Stokes, Jr., W. W. McCrory, and H. Stroud, in press. 

 2"i D. B. Coursin, J. Am. Med. Assoc, in press. 



