(1) That in the intervals between acute attacks of gout the elimination of uric acid lies within the normal limits, but that
(2) For one or two days prior to an acute attack an appreciable decline in the output of uric acid occurs. This, however, is not so marked as the subsequent
(3) Increased output of uric acid during the acute attack. According to Magnus Levy the increase may reach from 0·3-0·5 gram, daily, and more, and may sometimes last for a week or even two.
(4) Following attack a tardy decline in uric acid output to former level.
To sum up, during an attack of acute gout the uric acid output stands at a relatively low level between the paroxysms. But one or two days before the oncoming attack a diminution in uric acid output ensues. In contrast with the outbreak of the attack, the uric acid excretion increases markedly, this enduring for a week or more, when the output again declines. The augmented output during the paroxysm is more constant than the diminished excretion antecedent thereto. Now, while it may be taken that the foregoing variations in uric acid output, prior, during, and subsequent to, acute attacks, obtain as a general rule, such behaviour is not invariable; for, unfortunately, as Wells reminds us, instances are met with in which “the uric acid excretion shows no variation from that of normal persons.”
Uric Acid Variations in Chronic Gout
It must never be forgotten that the elimination of uric acid displays wide variations, this even when the subject under investigation is on a constant diet. Consequently, as Folin has pointed out, “even in the case of gout, which is distinctly associated with uric acid, it is an extremely difficult matter to prove by means of urine analyses that the uric acid elimination is not entirely normal.” And he adds, “If it had not been for the fact that uric acid, because of its insolubility, is so easily found in the joints, it would unquestionably have been a very long time before any definite relationship between uric acid and gout could have been established.”
None can gainsay the truth of these reflections, for, when placed on a fixed diet, the uric acid output in the victims of chronic gout differs but little from that of normal individuals on a similar regime; save in this respect, that, following the intake of purin-containing substances, the period of augmented uric acid excretion that ensues is prolonged as compared with the normal.