American Journal of Clinical Nutrition, Vol 12, 235-240, Copyright © 1963 by The American Society for Clinical Nutrition, Inc.

The Partition of Nitrogen in the Urine of Malnourished Jamaican Infants

¹ From the Medical Research Council, Tropical Metabolism Research Unit, University College of the West Indies, Jamaica, W. I.

Twenty-four-hour urine specimens were collected from malnourished Jamaican infants immediately after admission to the hospital, and at various stages of recovery. Measurements were made of urea, ammonia, creatinine and "residual nitrogen," which includes creatine, uric acid, amino acids and undetermined nitrogen.

The partition of urinary nitrogen agreed with Folin's concept of 1905; the proportion of urea nitrogen depended only on the amount of total nitrogen present.

The absolute amounts of ammonia nitrogen and residual nitrogen were relatively constant and no higher during malnutrition than after recovery. The urea nitrogen expressed as a percentage of the total nitrogen (i.e., the "urea index") may be useful for the assessment of protein intake.