The Case Report by Anastasakis et al. of a case of night blindness due to Vitamin A deficiency adds to an extensive prior literature. Indeed, Documenta Ophthalmologica has previously published similar cases, most recently in 2009. We have selected this case for publication not only for its novel features (malabsorption caused by GI malignancy; clinical and ERG improvement after Vitamin A therapy even though the initial serum Vitamin A levels were not subnormal), but also to maintain the awareness among our readers of this syndrome as one of the few, if not the only, treatable causes of night blindness.

A Pub-Med literature search turns up some 18 previously published cases of this disorder since 1976. Causes of the underlying Vitamin A deficiency have included gastro-intestinal bypass surgery (5 cases, at least three for intentional weight loss), other gastro-intestinal fistulas or Crohn’s disease (3 cases), 5 cases of hepatic disease (including primary sclerosing cholangitis, cirrhosis, and hepatitis C), malignant gastro-intestinal infiltration (due to mastocytosis), and at least two cases of psychogenic eating disorders (including anorexia nervosa) and one case of severe dietary restriction due to food allergies.

Though it has been stated that as many as 1/3 of such cases feature pale retinal flecks, only two documented cases appear in this search. Visual field abnormalities, often with irregularly shaped scotomas, are often noted and may not completely resolve with treatment. Responses to oral or parenteral Vitamin A therapy are generally dramatic, with subjective improvement often noted within 24 h of treatment, and improvement in the scotopic ERGs within 3 days.

We welcome further reports of fundus abnormalities and novel causes of the underlying Vitamin A deficiencies in this disorder.

Scott E. Brodie, MD, PhD

Associate Editor, Case Reports.