University of Bristol researchers said the boy’s unhealthy diet was mostly unchanged since he was 14, when he complained of tiredness to his regular doctor, according to a university press release.
At first, doctors noticed nothing particular about the boy, aside from being a “fussy eater.” His body mass index and height were normal, he had no visible signs of malnutrition, and he took no medications.
Still, tests showed the boy had macrocytic anemia and low vitamin B12 levels, which his doctor treated with vitamin injections and dietary advice.
A year later, the teen’s doctor noted hearing loss and “vision symptoms,” according to the researchers, but “no cause was found.”
At age 17, the boy was blind.
That was when doctors realized the teen’s diet was limited. Very limited, according to ophthalmologist Dr. Denize Atan, the lead author reporting the boy’s case in the latest issue of Annals of Internal Medicine.
“His diet was essentially a portion of chips from the local fish and chip shop every day,” Atan told the BBC. “He also used to snack on [chips] ― Pringles ― and sometimes slices of white bread and occasional slices of ham, and not really any fruit and vegetables.”
Atan said the patient told her that he had an aversion to certain textures and that “chips and crisps were really the only types of food that he wanted and felt that he could eat.”
The teen was eventually diagnosed with nutritional optic neuropathy ― damage to the optic nerve that results from nutritional deficiencies. The condition can be caused by drugs, malabsorption of food, poor diet or alcohol abuse, but “purely dietary causes are rare in developed countries,” LiveScience reported.
Vision loss from nutritional optic neuropathy can be reversed if the condition is found early enough, but the teen’s vision loss is permanent, doctors said. They added that nutritional supplements may prevent his vision loss from getting any worse.
The patient was referred to mental health services for his eating disorder.