Among the nitrogenous constituents of the urine, derivatives of ammonia are practically always present. Under normal conditions the quantity of ammonia thus eliminated by a healthy adult is not large; it usually amounts to less than half a gram per day. In certain diseased states, however, multiples of this quantity may be found in the urine. We do not refer here to the ammoniacal urines that result from bacterial decomposition of urea in the bladder and genitourinary passages, but rather to a metabolic component directly secreted by the kidneys.
There was a time, not many years ago, when this ammonia in the urine was looked on as the result of a pathologic disturbance in urea formation. In consequence of the deaminization of amino-acid complexes, ammonia is presumably continually being formed in the body and promptly synthesized into the characteristic final end-product of nitrogenous metabolism, urea. It is easy enough to