Other Anomalies in Excretion in Gout
As Levene and Kristeller have shown, side by side with the delayed excretion of ingested purins, there occurs also a tardy elimination of the other nitrogenous products of protein food. Vogt observed that fluctuations in nitrogen retention and nitrogen loss are quite typical of gouty subjects. As to the why and wherefore, however, of this variability, it remains a mystery. Nor do we know the form in which the nitrogen is retained, though Vogt maintains that the uneliminated moiety takes the form of purin bodies. According to Brugsch, it is during the acute attacks of gout that the nitrogen loss reaches its zenith, and he suggests that the nitrogen retention in the inter-paroxysmal periods is in part compensatory. On the other hand, the gain in weight that ensues is not adequate to account for the sum total of the nitrogen retention; while, as before observed, in gout there occurs, not only retarded elimination of exogenous purins, but also of other nitrogenous products of protein food. Yet, according to Heffter, the ratio of purin bases to uric acid is unaltered in the urine of gouty subjects.
Again, all nucleins contain a phosphoric acid group, and Futcher found that the curve of the uric acid output ran in a striking parallel with that of phosphoric acid. But the attempts of subsequent investigators to show that the two end-products of nuclein disintegration—uric acid and phosphoric acid—go hand-in-hand prove contradictory. Hence Wells, in regard to phosphoric elimination, observes that, “it seems probable that it shows no characteristic alterations in gout.” Lastly, we will recall to the reader that in the chapter on protein metabolism it was pointed out that the amino-acids, especially glycocoll, are found in excess in “gouty” urines.
In conclusion, it must, we fear, be admitted that the results of urinary analyses have proved insufficient of themselves to unravel the intricacies of metabolism in gout, and, after a brief digression, we shall proceed to ascertain whether, on the other hand, chemical analysis of the blood by modern methods can in any way shed further light on this obscure problem.