Quantitative chemical studies in spinal fluids

Abstract

Quantitative determinations of total, non-protein and urea nitrogen, creatinine, creatine and sugar have been carried out on spinal fluids of poliomyelitis and various forms of meningitis. Traces of ammonia, uric acid and cholesterol have also been demonstrated in these fluids.

With the exception of urea, which has been extensively studied by French workers, 1 quantitative studies in spinal fluids are comparatively meager, due undoubtedly to the fact that until recently, micro-methods not being available for these determinations, large quantities of fluid had to be used for any single chemical test.

The direct Nesslerization method for nitrogen determinations recently reported by Folin and Denis 2 has been with slight modifications adopted for the determinations of total, non-protein urea and ammonia nitrogen in spinal fluids. The total nitrogen in poliomyelitis is in the neighborhood of 25 mgm. per 100 c.c. In various forms of meningitis the total nitrogen was found to be considerably increased, extending from about 35 mgm. to 150 mgm. per 100 c.c. The non-protein nitrogen content is about 50 to 70 per cent. of the total nitrogen and urea, about 60 to 80 per cent. of the non-protein nitrogen. The determinations of ammonia were unsatisfactory because sufficiently large quantities of a single fluid required for a test were not available. Mixed water-clear sterile fluids obtained from poliomyelitis cases, were used. The results range from 0.1 mgm. to 0.9 mgm. of ammonia nitrogen per IOO C.C.

For the determinations of creatinine and creatine the Folin and Denis methods were employed. These methods have been recently criticized by McCrudden and Sargent 1 . The results nevertheless seem worth reporting in view of the creatinine and creatine studies on blood with the same methods. About half mgm. creatinine and from 0.3 to 0.7 of creatine were found in fluids examined.