Alpha-amino nitrogen in cerebrospinal fluid and its alterations in meningitis, multiple sclerosis, and some other neurological disorders.

The concentration of alpha-amino nitrogen (a measure of total amino-acids) was estimated in 58 samples of cerebrospinal fluid in which other findings were normal. Values for lumbar and ventricular cerebrospinal fluid in adults, and lumbar cerebrospinal fluid in children, are reported. A relationship was found between the concentrations of alpha-amino nitrogen in lumbar cerebrospinal fluid and in plasma.Alpha-amino nitrogen was also estimated in 79 samples of fluid from patients with meningitis, cerebral tumour, multiple sclerosis, and other neurological disorders. High concentrations were found in meningitis, spinal block, and xanthochromic fluids. In cerebral tumours, the concentrations were mostly normal. Low concentrations were found in children, in many cases of multiple sclerosis, and in benign intracranial hypertension. In some cases, the changes cannot yet be explained.