1. Rickets developed in three puppies deprived of vitamin D and sunlight since birth, in which, at the age of 6 to 7 weeks gall bladder fistula was established. The results of studies of their bones and of the calcium and phosphate metabolism have previously been published (2). Studies on the nitrogen, potassium, sodium, and chlorine metabolism, here presented, reveal that the metabolism was greatly interfered with as compared with that in three controls without gall bladder fistula rickets. This interference, together with an inhibited gain in weight, demonstrates that the pathogenesis of biliary, fistula rickets in puppies has to be considered distinctly different from infantile rickets as well as from rickets produced in rats.
2. The nitrogen, potassium, sodium, and chlorine metabolism was also studied in three rachitic and four healthy infants, and in eleven rachitic and six control rats. The balance of these substances, as well as their distribution in stool and urine, proved to be the same whether or not rickets was present.
3. The pathogenesis of biliary fistula rickets is discussed on the basis of these studies. The assumption has been made that deficiency in other vitamins than vitamin D might have a bearing upon the development of this disease. Further study with a view to possible elimination of these unspecific factors might lead to the experimental production by gall bladder fistula of a purely rachitic state.
4. The normal balance and distribution of nitrogen, potassium, sodium, and chlorine in the stool and urine of rachitic infants and rats are considered further evidence of the hypothetical nature of the so called absorption theory in infantile rickets.