Keep last records based on conditions, VBA or formula

Hi there,

I have a simple test file that I am trying to put a formula in to run, but i have not been successful. I have attached the file.

Basically, here is what I want to do:

1) Going down each record in column A, if the same patient(if patient ID is the same, then it's the same patient) has the same intake date. If the intake date is the same, but the admission date is different, then I ONLY want the first occurrence of the record and delete the other ones.
2) Looking at each patient ID in column A. If the same patient has the different intake date, but their admission date is the same, then I want ONLY the last occurrence of the record and delete the other ones.

I was trying to use a formula for it to work, but I have not been successful. It seems that I am always half way there.

Any help is appreciated.

Thanks