Medical case narrative
A young boy, vitamin D, and the difference between a case and a claim
What happened
A boy of 32 months with autism had a vitamin D level of 31.3 nmol/L — deficient. On supplementation, his level rose to 203 nmol/L, and his measured scores improved: the ABC scale fell from 80 to 39, and CARS from 35 to 28.
What it looked like
A developmentally delayed toddler with a genuine, measurable deficiency.
What the labs found
Vitamin D deficiency — real, and worth treating on its own terms.
What changed — and what didn't get proven
His scores improved alongside repletion, and two review papers have re-reported this case. But both reviews retell one uncontrolled case, and a 2017 randomized controlled trial of vitamin D in autism (Kerley) found no effect. This entry is here as a contributor story at its honest weight: correct a deficiency because it is a deficiency, and let controlled trials decide the bigger claims.
The test that told the story
25-hydroxyvitamin D.
Sources: Original case as re-reported in two reviews; Kerley 2017 RCT as counterweight.