THE CALCIUM AND PHOSPHORUS CONCENTRATION IN THE SERUM OF INFANTS WITH MILD RICKETS OR A CONDITION SIMULATING MILD RICKETS

Howland and Kramer¹ recently reported the results of an investigation of the calcium and inorganic phosphorus in the blood serum of infants with active rickets, and conclude that in the active stages of this disease the serum phosphorus is regularly reduced. The constant occurrence of some evidence of rickets in cases of tetany referred to by the older writers, and again recently emphasized by Brown and his co-workers² is now generally recognized. The calcium and phosphorus content of the serum of infants with active tetany have been determined by Kramer, Tisdall and Howland,³ who found that the calcium was markedly reduced in all instances and in about half the cases the concentration of the inorganic phosphorus was normal or even above normal. As a result of these investigations it may be concluded that in active rickets the serum phosphorus is markedly reduced while in mild rickets associated