Studies on Metabolism in Pneumonia

The concept of an increased formation and excretion of acids in pneumonia seems to have first found experimental justification in the work of Palmer and Henderson (l), who found that the administrat,ion of 4 gm. of sodium bicarbonate did not appreciably change the reaction of the urine of a patient with pneumonia. In normal individuals this amount of bicarbonate produced a change in reaction of approximately pH 1.7. Later, Palmer (2) determined the buffer values of urine from a pH of 7.4 (neutral red) to one of pH 5.0 (alizarin). After subtracting the buffer value of the phosphate content, it was found that the remainder was, in some pneumonia urines, considerably greater than in normal urine. This increase was ascribed to the presence of organic acids. The technique for the determination of organic acid was greatly improved by Van Slyke and Palmer (3). Phosphate was precipitated by means of Ca(OH)2, thus obviating the necessity for a phosph’ate determination and a correction based thereon. Van Slyke and Palmer recognized that weak bases would titrate as do weak acids by their technique and they introduced corrections for the creatinine and creatine content of the urine. They mentioned the possibility of the presence of other bases of unknown nature but considered this to be extremely unlikely. Using this method, Clausen (4) made a number of determinations of the organic acid content of the urine of children with pneumonia. He found that large quantities were excreted and that the maximum output coincided with the period of resolution.