Concentration of vitamin A in the liver of foetuses and infants dying of various causes in Brasilia, Brazil.

The vitamin A concentration in liver samples taken at autopsy from the central portion of the right lobe of 57 infants 0-1 year old was determined by a dual spectrophotometric and colorimetric assay. Death was due to respiratory disease (30%), complications of premature birth (16%), infections (14%), hemorrhage (14%), pneumonia (10%), cerebral edema (7%), and miscellaneous causes (9%). Gross malnutrition was noted in only 2 of these children. The median vitamin A concentration was 61 micrograms of retinol/g liver, with a range of 6-293 micrograms/g. The percent distribution of liver vitamin A levels in micrograms/g was: less than 5 (0%); 5-10 (7%); 10-20 (5%); 20-40 (16%); 40-80 (42%); 80-120 (14%); greater than 120 (16%). The mean liver level in 9 stillborn full-term infants (60 micrograms/g) was markedly lower than in 7 stillborn premature infants (125 micrograms/g). The median value for 22 infants from indigent families (54 micrograms/g) was lower than that of 35 infants from non-indigent families (65 micrograms/g). By applying the criteria that liver reserves of vitamin A less than or equal to 5 micrograms retinol/g of liver indicate a high risk of vitamin A deficiency and those less than 20 micrograms retinol/g of liver denote an inadequate reserve, no infant was at high risk but 12% had insufficient reserves.