Well I would consider to be based on 3 tables (4 if you looking for different permissions for stuff like nurse can only search and view records, doctor can search, view, edit and create new record)
Table 1 - patients personal details (unique patient ID, DOB, contact details, basic medical records such weight, height, eyes check, alergies or any disabilities)
Table 2 - regular checks (unique patient ID plus what ever medical procedures taken/given that can work as foreign key for you)
Table 3 - illnessrecord (unique patient ID, illness descriptions, any prescrioptions, possible next check)

This is sort of things you looking for in general, if you want to get deeper in given problem you would have to reaserch on what sort of records instituson is interested to store