I am pretty sure my 78 year old mom has Alzheimer's but gets very defensive and depressed if we mention her memory issues. She won't make an appointment to get an assessment, and I am afraid to make her go or make one for her. So how important is it to have that official diagnosis? I know there is medicine to help, but is it worth forcing her to go and possibly devastating her by the diagnosis not to mention animosity between us. Nor sure what to do.
There is no medicine that "helps" Alzheimer's like I think you are implying. But ALZ can have a different prognosis than dementia. Does anyone have durable PoA for her? Someone other than her now needs to be closely involved in her medical care. If she has something other than a UTI, she will need an advocate with her at ALL appointments and even if she needs to take meds.
I must assume that you have in place DPOA or POA and paperwork, wills and etc are set up so that you will be able to protect your Mom. She will still be capable of taking care of these things, but when diagnosed with dementia and unable to answer questions of any examining Lawyer to prove that she understands the directions she is setting up, it will be too late.
Remember, in early dementia the long term memories are strong, but what you watched on TV together last night are NOT.
Now as to testing, that is going to be hard to force on someone who is currently having memory problems only. What other symptoms are you seeing? Are you Medical POA and can you suggest to her MD that he examine for some of these issues on a regular yearly exam?
What matters now are issues of safety for Mom. You can start a diary on your own of things that worry you that you are seeing. One of the hallmarks of early dementia would be anger and defensiveness when the subject is brought up. For instance if you said to me "Mom, can I talk to you about a few instances I have noted that are of concern to me " I would say "Sure." And if these instances were honestly presented--well, I guess I would say "ONE of us is sure suffering from a mental deficit. I am 78, so I better get tested FIRST" hee hee. If you see what I mean, the kickback is hard when there is fear and often someone who is in the beginning stages is noticing things him or herself that are worrisome.
Wishing you good luck going forward.