Medical

What’s causing this teenager’s vision loss?

A 14-year-old boy is brought to the pediatrician by his mother over concerns of difficulty walking and worsening clumsiness. He reports a gradual loss of night vision, and a long history of chronic diarrhea which is pale and foul-smelling. Examination reveals an ataxic gait, and loss of deep tendon reflexes. Bilateral retinitis pigmentosa is noted on fundoscopy and a peripheral blood smear reveals the findings seen here. Which additional laboratory finding is most likely?
A. Low total cholesterol level
B. Elevated calcium level
C. Low vitamin B12 level
D. Elevated alpha-tocopherol level

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Explore cases, quiz yourself, and solve medical mysteries along with thousands of other medical professionals around the world on Figure 1, the free app where doctors expand their clinical knowledge. Explore cases, quiz yourself, and solve medical mysteries along with thousands of other medical professionals around the world on Figure 1, the free a...