Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Carotenes are provitamins, or precursors of vitamin A. They produce the orange color observed in carrots, sweet potatoes, cantaloupe, and many other fruits and vegetables. Both elevated and deficient levels of carotene can have clinical consequences for patients.
The highest levels of carotene can be found in the serum of individuals ingesting large amounts of vegetables, primarily carrots. These people may have a slight yellowish tinge of the skin, but the sclera of the eye is not discolored. More moderate elevations can be observed in patients with diabetes mellitus, myxedema, hyperlipidemia, or chronic nephritis.
Decreased serum levels may be seen in individuals with nutritional deficiencies including anorexia nervosa, malabsorption, and steatorrhea.
Lycopenemia, in which a patient has a yellow-orange pigmentation of the skin, is a very rare condition resulting from excessive consumption of lycopene-containing fruits and berries. Individuals with lycopenemia have normal carotene levels.
Detection of a nutritional deficiency of carotene or lipid malabsorption
Detection of excessive ingestion of carotene
Investigation of lycopenemia
Normal: 48 mcg/dL to 200 mcg/dL
High: >400 mcg/dL
Moderately high: >300 mcg/dL
Low (malabsorption): 20 mcg/dL
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Patient must be fasting for 12 to 14 hours and consume no alcohol or nutritional supplement for 24 hours prior to specimen collection.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Clinical References Provides recommendations for further in-depth reading of a clinical nature
1. Maharshak N, Shapiro J, Trau H: Carotenoderma - a review of the current literature. Int J Dermatol 2003;42(3):178-181
2. Karthik SV, Campbell-Davidson D, Isherwood D: Carotenemia in infancy and its association with prevalent feeding practices. Pediatr Dermatol 2006;23(6):571-573