I was diagnosed with normal pressure hydrocephalus i'm 31 years old 1 seizure as baby no brain surgery no stroke 1 c section for twins in 2020 what could cause someone my age to get it? what infections if any? life expectancy for my age of diagnosis?

"Normal pressure hydrocephalus" can be associated with injury, bleeding, infection, brain tumor, and "life expectancy" will of course depend on the cause. If not already accomplished, obtain a referral to a neurology physician for appropriate testing and treatment.

There are numerous hormonal, endocrinological, antibiotic causes among the etiologies. Even excessive vitamin A exposure could be a culprit. Prior meningitis or subarachnoid hemorrhage can cause. Search for underlying etiology should be handled by a seasoned neurologist. Would not expect compromise of life expectancy necessarily with appropriate management.