Cheryl, 46, presents with worsening fatigue for the past few months. She is usually well, takes no medications and does not drink or smoke.
Her menses have been heavier and more frequent over the past year, which she attributes to known fibroids and perimenopause.
Oddly, she has been craving brussel sprouts and pumpkin and has been including these in most meals for months.
On examination, Cheryl has a tachycardia of 110bpm at rest; her vital signs are otherwise normal, and her BMI is stable at 21kg/m2. Palmar discolouration is noted (pictured), with the nasolabial folds and soles also affected.
She has pale conjunctivae but no scleral icterus. Examination is otherwise normal.
Pathology is significant for iron-deficiency anaemia. Beta-human chorionic gondatropin, coeliac serology and FOBT are negative.
What is the most likely diagnosis?
Correct!
In this case, food cravings — thought to be secondary to iron deficiency from heavy menstrual bleeding — have driven increased ingestion of beta carotene–rich foods, resulting in carotenaemia with associated carotenoderma.
All pigmented fruits and vegetables contain carotene, with deep-yellow, orange and green foods having a particularly high carotene content.
Excessive dietary intake of carotene-rich foods is the most common cause of carotenaemia. Rarely, it may be a manifestation of systemic disorders, including diabetes, glomerulonephritis, hypothyroidism, restrictive eating, hepatic disease and hyperlipidaemia.
Carotenoderma presents as a yellow–orange discolouration that is most marked on the forehead, nose, nasolabial folds, palms and soles. It is more prominent under artificial light.
The discolouration reflects deposition of carotene in the fat-soluble stratum corneum. It is most obvious in regions with high sebum or sweat production and where the stratum corneum is thickest. The sclera and mucous membranes lack a stratum corneum so are always spared.
The diagnosis is typically clinical, although investigations may be considered to exclude secondary causes. An elevated serum carotene in the setting of normal liver function and normal to slightly elevated vitamin A levels are in keeping with the diagnosis.
Reduced ingestion of carotene-rich foods will reverse intake-related carotenoderma, but this may take several months. Iron administration is swiftly effective for pica-related cravings, which usually respond well before haematological parameters normalise.