Carotenemia
Carotenemia is a common finding in children, mainly due to the excessive intake of carrots, but it can also be associated with the ingestion of many other yellow and green vegetables and citrus fruits. Carotene is a lipochrome that normally adds yellow color to the skin. With elevated blood levels of carotene, the prominence of this yellowing is increased. Carotenemia may be particularly evident when the stratum corneum is thickened or when the subcutaneous fat is strongly represented. The condition of carotenemia is harmless, but it can lead to a mistaken diagnosis of jaundice.
Awareness of carotenemia may avoid confusion with jaundice and unnecessary diagnostic studies. Mothers may induce it by giving their infants large amounts of carrots in commercial infant food preparations.1 Hypothyroidism,2 diabetes mellitus,3 hepatic diseases, anorexia nervosa, and renal diseases may be associated with carotenemia unassociated with the ingestion of carotene.4 Carotenemia may also be associated with the ingestion of carotene-rich nutritional supplements.5
Red hues are a challenge for animal coloration, as multiple pigments such as carotenoids, pheomelanin, psittacofulvins, porphyrins, turacin, and hemoglobin may confer red colors.6
Also see the eMedicine Pediatrics article, Carotenemia.
Excessive intake of vitamin A precursors in foods, principally carrots, can lead to a yellow discoloration of the skin but not of the sclera and oral cavity. This condition most commonly occurs in children with liver disease, hypothyroidism, or diabetes mellitus. The absorption of dietary carotenoid requires dietary fat and is enhanced by administering with meals. The conversion of beta-carotene (provitamin A) to vitamin A is accelerated by thyroxine and hyperthyroidism. Excessive ingestion of carotenoids is nontoxic and does not cause hypervitaminosis A because the conversion of carotene to vitamin A is slow.
This disorder most commonly occurs in vegetarians and young children.
Carotenemia is a benign condition.
Carotenemia is more easily appreciated in light-complexioned people, and it may present chiefly as yellowing of the palms and the soles in more darkly pigmented persons.
Carotenemia may occur at any age, but it is most common in children.
- A history of excessive carotene intake consistent with the diagnosis of hypercarotenemia is usually present. Carotenemia can be verified by a high serum beta-carotene level, a normal or slightly elevated vitamin A level, and normal liver function test results. Accumulation of beta-carotene in the skin is delayed by up to 2 weeks compared to the serum. Because of the lipophilic nature of carotenoids, sufficient amounts can remain in tissue for several months, causing yellow skin even after serum carotene levels return to normal.
- Metabolic carotenemia without a history of excessive carotene intake may be due to a genetic defect in the metabolism of carotenoids.
- Amenorrhea may be associated with carotenemia. This occurs in patients who consume a pure or predominantly vegetarian diet without red meat. Dietary modifications can reduce carotene levels, which, in turn, normalize the menstrual cycle.
- A correlation between metabolic carotenemia and biliary dyskinesia has been suggested. In patients with metabolic carotenemia, significant relationships were identified between the gall bladder contraction rate and the levels of serum carotene, vitamin A, and lipids.
- Carotenemia may be due to the ingestion of red palm oil. Because of the lipophilic nature of carotenoids, sufficient amounts may remain in the skin to produce discoloration for up to 5 months, even if serum beta-carotene levels have returned to normal.
- Yellow skin discoloration, especially on the palms and the soles, without affecting the sclera, is present.
- Yellowish pigmentation of the skin (xanthoderma) may be caused by many conditions.
- Ascertaining the presence or the absence of scleral icterus is important in determining the diagnosis.
- Yellow sclerae are found in patients with all etiologies of elevated serum bilirubin because scleral tissues are rich in elastin, which has a special affinity for bilirubin.
- The liver and the spleen are not enlarged.
Causes
- Excessive intake of carotenoid-rich vegetables (mainly green and yellow) and fruits causes carotenemia.
Treatment
Carotenemia is a benign condition that improves with dietary modification.
Recommend a diet without excessive carotene.
