Normal faecal porphyrin values in babies.

Normal faeces contain both coproporphyrin and protoporphyrin in very small quantities. These arise in part as by-products from haem synthesis which are excreted via the bile into the gut, in part from degradation of ingested haem, and possibly also in part by bacterial synthesis in the intestine. In adults normal values (Barnes, 1957) are: coproporphyrin, 0-15 ug. per g. dry weight; and protoporphyrin, 0-45 .lAg. per g. dry weight. The purpose of this investigation was to establish normal values in babies from birth up to 1 year of age. Only one reference in the literature has been found to porphyrin determinations in babies and children (Fokina, 1947), but, whereas Fokina has estimated average faecal elimination values per 24 hours, these values are expressed as micrograms per gramme dry weight and therefore the two investigations are not strictly comparable.