In high-income countries, diseases related to vitamin deficiencies are not as frequent as in poorer settings but are nonetheless regular occurrences. In a Clinical Picture published Online First and in next week's Lancet, the case of a 24-year-old pregnant woman suffering vitamin A deficiency is reported. The Clinical Picture is written by Dr Stephen H Tsang, Edward Harkness Eye Institute, Columbia University Medical Center, New York, USA, and colleagues.
The woman presented to New York-Presbyterian Hospital with a 7-week history of progressive loss of vision, mostly at night. Tests of her eyes using electroretinography revealed a severe dysfunction in the rod and cone cells responsible for vision, and other irregularities in each eye. A blood analysis revealed vitamin A deficiency—the woman had a concentration of less than 0.002 µmol/L, well below the normal range of 0.70—2.8 µmol/L. Following vitamin A supplementation, her vision returned to normal.
The authors say: "Vitamin A deficiency can be secondary to poor intestinal absorption due to weight loss surgery, Crohn's disease or pancreatic dysfunction. Our patient had anorexia nervosa and had limited her diet to white onions, white potatoes, and red meat for the past 7 years."
The authors add that a 'steal effect'—in which the fetus takes the vital vitamin A it needs from its mother— could also have contributed to the woman's symptoms.
Dr Tsang adds: "It is essential to diagnose and treat this potentially curable form of blindness."