A certificate of analysis answers one question and gets quoted as though it answers four. Not on taurine but the pattern is familiar.

Reference ranges differ between labs, so comparing two reports is close to meaningless.

Is a baseline blood test really necessary before starting something like this?

A certificate of analysis answers one question and gets quoted as though it answers four.

You have two changes at once here. You cannot attribute anything until one of them moves. How long have you been on ventilation in winter?

Same here.