284 LACTOSURIA 



LACTOSURIA 



Another anomaly of metabolism of some physiological 

 interest is lactosuria. 41 



The study of this condition began with a discovery by 

 Hofmeister in 1877 of a reducing substance in the urine of 

 lying-in women which he recognized as milk-sugar. 



Since then we have framed fairly clear conceptions of 

 the conditions under which lactose passes into the urine. 

 We know as the ability to hydrolyse the milk-sugar and to 

 make full use of it is missing from the blood and the tissues 

 generally, that lactose thus entering the circulation paren- 

 terally is excreted in the urine, as above noted. It is pos- 

 sible that the animal economy may in a measure acquire the 

 ability to split milk-sugar parenterally and utilize it if re- 

 peated injections of milk-sugar be given 42 ; but at any rate 

 this capability does not exist in the normal body. 



Lactosuria of Puerperal Women. There is nothing re- 

 markable in the fact that if a woman in the puerperium sud- 

 denly has an interruption of suckling her infant and of thus 

 eliminating large amounts of milk-sugar in her milk, the 

 breasts do not at once stop producing lactose. This pent-up 

 lactose will eventually be resorbed into the blood and thence 

 naturally pass into the urine. Lactosuria, therefore, often 

 appears, and has been frequently observed, as a reaction 

 of the system to a sudden weaning ; and may continue for a 

 long time, especially in good nurses. In milk-cows lacto- 

 suria is a physiological phenomenon. 43 



Again, lactosuria may occur shortly before delivery, as 

 at this time the mammary glands are beginning to assume 

 their duty and even the colostrum contains lactose. C. v. 

 Noorden and Zuelzer have observed even in cases of abor- 



41 Literature upon Lactosuria: C. Neuberg, Handb. d. Pathol. d. Stoffw., 

 2, 238-241, 1909; A. Magnus-Levy, Handb. d. Biochem., 4', 378-384, 1909. 



42 Cf. J. S. Leopold and A. v. Reuss (Pediatric Clinic, Univ. Vienna), 

 Monatschr. f. Kinderheilk, 8, 1, 453, 1909. 



48 Sieg, Arch. f. Tierheilkunde, 35, 114, 1909, cited in Jahresber. f. Tierchem., 

 39, 663, 1909. 



