Herman Wortis

PATHOLOGICAL VARIATIONS IN BLOOD AND SPINAL FLUID PYRUVIC ACID.

Pyruvic acid is a normal intermediary of carbohydrate metabolism (1, 2). It has been previously demonstrated that thiamin, or more particularly thiamin pyrophosphate (cocarboxylase), is concerned in the normal catabolism of pyruvic acid (1). In Oriental beri-beri (3) and peripheral neuropathy in the alcohol addict (4)-both diseases associated with a deficiency of thiaminhyperpyruvemia does occur. Pyruvic acid is a keto acid and therefore a bisulfite binding substance. Previous investigators (5, 6, 7) have frequently used the measurement of the total bisulfite binding substances (B.B.S.) as an indication of the pyruvic acid level of the blood. More recent work (8, 9, 10, 11) indicates that this is not justified and that a more specific method for pyruvic acid must be used. Utilizing such a method, we have determined the concentration of pyruvic acid in 60 normal subjects (12). The figures varied from 0.77 to 1.16 mgm. per cent, the average being 0.98 mgm. per cent. Wehave considered as abnormally high cases with blood pyruvic acid levels above 1.30 mgm. per cent. The spinal fluid pyruvate is 70 to 120 per cent of a corresponding blood sample (average 82 per cent) (13). The present study was undertaken in order to determine the clinical significance of the pyruvic acid levels in blood and cerebrospinal fluid.

Bisulfite Binding Substances (B.B.S.) in the Blood and Cerebrospinal Fluid.

Conclusion The amount of N/200 I2 corresponding to the liberated bisulfite is equivalent to the total I2 minus the thiosulfate. The value of the blank is then deducted from this figure. This difference is then multiplied by 3.67 for the blood sample and 2.75 for the spinal fluid sample. The result obtained equals the total B.B.S. expressed as mg of pyruvic acid per 100 cc.

Pyruvic Acid in Blood and Cerebrospinal Fluid.

Summary 1. The stability of pyruvic acid in the spinal fluid is described. 2. The relationship of blood to spinal fluid pyruvate is reported. The amount found in the cerebrospinal fluid is usually 70-120% of that found in a blood sample taken simultaneously. 3. Of the 16 cases with elevated blood pyruvate, 13 occurred in cases of known vitamin B1 deficiency. These latter constituted the only cases in the entire study with definite clinical evidences of vitamin B1 deficiency. In the other 3. it is suggested that a relative deficiency of vitamin B1 may have existed. In 51 additional cases, without clinical evidence of vitamin B1 deficiency, the blood pyruvate was normal in every instance.