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Editor,—Vitamin A deficiency due to malnutrition is the leading cause of childhood blindness worldwide1 but is rarely seen in developed countries. Although case reports of xerophthalmia in developed countries have appeared in the general medical2 3 and ophthalmic literature,4 5the relative rarity of the condition can lead to delay in diagnosis with potentially serious consequences. We present a patient with short bowel syndrome whose grossly depleted vitamin A stores only came to light with the onset of severe ocular surface disease.
The patient, now 8 years old, was born after a normal pregnancy by breech delivery at 36 weeks. At age 1 day he developed abdominal distension with bile stained vomiting. At laparotomy multiple small bowel atresia were excised and a jejunostomy fashioned. This was closed 3 weeks later and replaced by a jejuno-jejunal anastomosis. The latter required two revisions (at 10 days and 2 months after the initial anastomosis) with excision of more bowel and division of adhesions. For the first few months he was fed only intravenously, this being very gradually replaced by oral feeding over the subsequent 4 months. Vitamin and mineral supplements were included in his diet up to age 2 years. He has always been of small stature and low weight (below 3rd centile for both factors) and prone to recurrent infections and had frequent (up to six a day) motions which tended to float. Epiphyseal maturation has been delayed (bone age at 7.9 years of age was equivalent to that of a 3 year old child). He had dry flaky skin which was thought to be due to eczema. After his family moved he was lost to hospital follow up and general practitioner review had only been intermittent.
His mother had noted red eyes and swollen lids over the previous 2½ years. Difficulties seeing in the dark were also apparent. His grandfather recalled taking him to the cinema some 3 years earlier and noting that the child appeared not to see in the dark. A tentative diagnosis of allergic conjunctivitis had been made at a casualty department and topical steroid drops had brought about temporary improvement in the redness of his eyes. However, in the 3 months before presentation to us, the redness had recurred with increasing discomfort, sensitivity to bright light and decreased vision causing distress and severe disruption of education. Treatment with topical lubricant, antibiotics, and steroids was ineffective. He was referred to us for a second opinion regarding his chronic ocular surface problems.
At examination he had great difficulty in opening his eyes because of discomfort and photophobia. Visual acuity was reduced to hand movements in both eyes. The skin of the eyelids was red and thickened and the eyelashes were excessively long. Both eyes were injected but most striking was the marked xerosis of the conjunctiva and absence of corneal lustre. Both corneas showed confluent punctate staining with fluorescein but no epithelial defects or new vessels. Schirmer’s test was normal but the ocular surface on both sides was totally unwettable. A diagnosis of vitamin A deficiency was made on the basis of his ocular signs. The child was then initially treated by his local paediatric team and referred on to Great Ormond Street for further care.
Biochemistry showed multiple deficiencies, in particular of the fat soluble vitamins and calcium (Table 1). His prothrombin time was prolonged. Endoscopy revealed chronic oesophagitis and dilated residual small bowel loops and a hydrogen breath test was suggestive of bacterial overgrowth. Treatment based on the World Health Organisation guidelines,1 with 100 000 IU of vitamin A intramuscularly, oral vitamin K, and subsequently oral Ketovite and Forceval (vitamin and mineral supplements) and other supplements resulted in improvement in ocular symptoms and signs within 5 days. Two weeks after starting treatment, his visual acuity had recovered to 6/9 right eye, 6/6 left eye and examination was normal apart from a faint subepithelial corneal opacity just below the visual axis in the right eye. Systemic antibiotic therapy for the bacterial overgrowth was also instituted.
In developed countries vitamin A deficiency is seen in patients with severe liver disease leading to storage and metabolic abnormalities. Bowel disease or surgical shortening3 6 can cause insufficient absorption resulting in deficiencies as in our patient. The amount and site of bowel resected determines how much tolerance and adaptation can take place. Chronic nutritional deficiency states, liver disease, and bacterial overgrowth are common complications.6 Bacterial overgrowth can exacerbate the malabsorption and this was probably the case with our patient. The manifestations of hypovitaminosis A appear after prolonged depletion. This can often mean a significant time lag between the causative event and presentation.5 7
As vitamin A plays a key role in the elaboration of visual pigment, night blindness is often the earliest sign of vitamin A deficiency. Bitot spots and xerosis of the ocular surface occur after more prolonged deficiency. Keratomalacia is a liquefactive necrosis of the cornea leading to scarring or perforation. The latter may be precipitated by intercurrent infection1 creating demands that cannot be met by the depleted stores of vitamin A.
The importance of a complete medical history is demonstrated by this case. While the early ocular manifestations of hypovitaminosis A are readily reversible,2 4 7 the late changes cause permanent corneal damage and visual loss. In addition, there is an increased childhood morbidity and mortality8 associated with vitamin A deficiency which can be reduced by restoring vitamin A levels to normal.9
Night blindness had been present for at least 3 years and the initially mild lid and conjunctival changes were misinterpreted as being secondary to allergy, possibly because the patient’s skin condition (itself the result of vitamin A depletion, hyperkeratosis) was thought to reflect atopy. Although the clinical presentation was entirely consistent with vitamin A deficiency, the diagnosis was not initially considered because it is so infrequently encountered in developed countries, resulting in an unnecessary delay in instituting the correct treatment.
A history of previous bowel resection, in the presence of ocular surface abnormalities, should raise the possibility of inadequate absorption and storage of essential vitamins. Patients with short bowel syndrome need regular review and screening for possible deficiencies.2-4 6 7