The urine sample should be perfectly fresh and not long exposed to light.
Amount of Urine in 24 Hours
Normally a man passes about 1200 cc. of urine in twenty-four hours, a woman somewhat less. When the amount is under 750 cc. we have an oliguria. To consider a polyuria as present the patient should pass more than 3000 cc., as this amount may be considered the upper normal limit. In anuria we have a cessation of renal activity.
The disease in which anuria is most characteristic is cholera. During the stage of evacuation the urinary secretion becomes less and less along with the progressive failure of circulation and, during the algid stage, we have a suppression of urine.
The anuria seems to run parallel with an acidosis and intravenous injections of bicarbonate of soda solutions tend to prevent anuria. In the stage of reaction the favorable outcome is the reappearance of urine, which increases in amount to become a polyuria. In unfavorable cases the anuria continues.
In blackwater fever anuria may result from the blocking up of the renal tubules by haemoglobin casts.
Blackwater fever also shows an acidosis and alkaline treatment is here indicated. Blackwater urine is irritating so that there is vesical tenesmus with frequent urination.
The degree of renal involvement is of great prognostic value in yellow fever, and those cases where the oliguria goes on to suppression are apt to terminate fatally.
In heat stroke there is an oliguria or anuria which may be followed, during convalescence, by a polyuria. Marked irritation of the bladder, associated with suppression of sweating, may be indicative of oncoming heat stroke.
In dropsical beriberi there is an oliguria or, rarely, an anuria which with the rapid disappearance of the general body oedema may become an excessive polyuria.