It would be unfortunate if the comments of Allen1 were widely interpreted as minimizing the risks inherent in sodium depletion. While it is true that observations of a large requirement of sodium and a dramatic rise of the level of blood urea in patients with nephritis who receive a diet restricted in sodium are somewhat unusual,2 less rapidly developing, but equally dangerous, changes occur not infrequently when sodium depletion is employed routinely for congestive cardiac failure and for hypertension.
The case histories noted herein are only 3 of the many which have impressed me with the importance of observing the levels of blood urea or creatinine in any patient receiving such treatment.
Report of Cases
R.M., a 38 year old bookkeeper, entered the hospital because of impaired vision of the left eye, which had occurred suddenly six days previously and had persisted until admission. He had relatively