He could qualify TBI...traumatic brain injury. And then in the paperwork somewhere you need to note that unless school assignments or writing tasks will only take 5 minutes out of his whole day for the rest of his life any observation or assessment needs to realistically mimic the actual workload task found in school, such as an essay expected to be completed in 45 minutes of straight writing.

...reading is pleasure, not just something teachers make you do in school.~B. Cleary