Vitamin A deficiency is a common cause of blindness in developing countries. Around 2.8 million preschool children are affected with vitamin A deficiency in over 60 countries and subclinical vitamin A deficiency is considered a problem for at least 251 million people.3
However, it is rare in developed countries and is usually only encountered in patients with malabsorptive states or liver disease.
Being a liposoluble nutrient, vitamin A is dependent on the dietary lipids for transport. The reduction of dietary lipids into its more simple forms for transport is carried out by the pancreatic enzyme lipase. As a result, any pancreatic impairment can limit vitamin A absorption and transport.
In a pancreaticoduodenectomy, the head of the pancreas, a portion of the bile duct, the gallbladder, the duodenum and sometimes part of the stomach is removed. The surgery can result in reduced enzymatic production and, hence, necessitates dietary supplementation in patients.
Here, our patient presented with nyctalopia, which is one of the earliest symptoms of vitamin A deficiency. He had stopped taking his pancreatic supplements about a year before he started developing the symptoms. He did not have other ocular complications seen in prolonged vitamin A deficiency, which includes conjunctival and corneal xerosis, Bitot's spots, severe punctate keratitis, corneal scarring and ultimately keratomalacia in severe cases.
The other symptoms that he presented with, that is, the weight loss and the skin dryness, can also be attributed to vitamin A deficiency. It is also possible that he might have had subclinical vitamin A deficiency when he was in ICU for severe pneumonia.
Here, the diagnosis was made promptly and allowed treatment to be instituted before his symptoms progressed. However, it can easily be missed, especially in developed countries where vitamin A deficiency is rare.
Vitamin A deficiency has been previously documented in patients suffering from chronic pancreatic insufficiency (alcoholic pancreatitis, cystic fibrosis) and in intestinal bypass surgery.2 4–6
These studies have had success with both oral and intramuscular treatment of vitamin A. However, it is evident that the normalisation of vitamin A levels is achieved quicker with intramuscular treatment.3 5
Our case emphasises that patients who have had a pancreaticoduodenostomy procedure need to be monitored closely from a nutritional point of view. Before undergoing any pancreatic surgery, the possibility of blindness from lack of vitamin A intake must be discussed with the patient. In particular, there is a need to stress the importance of compliance with nutritional supplements after surgery, even many years down the track.
- Vitamin A deficiency can occur in patients who have had pancreaticoduodenostomy, even many years after the surgery.
- Night blindness is an early sign of vitamin A deficiency – recognition of this and instituting early treatment can prevent devastating late complications.
- Vitamin A deficiency can be treated effectively with either oral and intramuscular treatment.
- Patients who undergo a pancreaticoduodenectomy or other similar procedures need to be counselled about the importance of maintaining their nutrition.