How does the doctor know it's Alzheimer's and not dementia?

Dementia is an umbrella term covering Alzheimer's, vascular dementia, Lewy body dementia, frontotemporal and others. All are cognitive disorders that usually have symptoms that, through office tests and often brain scans, a neurologist can diagnose. New tests for the future will include blood tests and saliva tests. A spinal fluid test is sometimes available but I'm not sure that it's covered by any insurance at this time.

There are many misdiagnoses. Additionally, people can have more than one type of dementia. People with Parkinson's often develop dementia. People with vascular dementia may also have Alzheimer's.

So, yes, it's complicated. Even the best doctor can be wrong. However, diagnosis is getting better. The problem is that there is, at this time, no treatment for most types of dementia. There are drugs that can be used for Alzheimer's that may - and the key word is may - slow symptoms for a time in some people.

The Alzheimer's Association does a good job of explaining symptoms but in the end working with a good neurologist will likely give you the best answer.
Take care,
Caro

My father also had alzheimers. Its true they cannot be certain until after autopsy. But if an mri is done they find the brain to have lesions in the alzheimers patient. You have to be very careful that what they are being treated for is alzheimers. Many patients develop symptoms that mimic it from a uti. These patients can act very psychotic and have dementia symptoms. And doctors seems to readily give these meds before ruling everything else out and can be harsh and if stopped can make patient worse than before starting. I speak from experience. Another thing to check is B12 levels. Older adults can't simulate this vitamin in their stomach many needs shots. (Should have on sublingual B12 vitamins anyway) Knew of an elderly woman put in home bc of dementia symptoms after receiving B12 shots was back to normal and able to live on her own again. Don't get me wrong meds for alzheimers can be a godsend and the earlier started the better. Not a cure but can slow patients progression way down. Hope this helps some:)

Rather than to try to get an exact definition, it might be easier to :

1. make sure that all other possibilities are exhausted (as in a urinary tract infection, vitamin deficiency, etc), and

2. plan survival strategies, life strategies.

I never got a definitive diagnosis for my mom but I sure knew something was wrong.

Alzheimer's Disease is one of many dementia. He checked symptoms and did some tests that gave him an idea. Unfortunately, you can only tell exactly which form after death, with a brain autopsy.

You really need to know correct dementia diagnosisAlzheimer's disease and dementia, there is a distinct difference, other dementias: Vascular dementia, Parkinson'sdisease, dementia with Lewy Bodies and Frontotemporaldementia. Some causes of dementia aretreatable and evenreversible. source: Mayo Clinic tinyurl/qdgj9g

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Our primary doc said he thought mom had some dementia long before we noticed more then the forgetfulness. He then sent us to a neurologist and he said alz. Few years later he then said it was Lewy body because she was presenting with more classical signs of that type then Parkinsons was diagnosed. My advice to you is to write down any and all things not usually done or used to do that you notice. My opinion, the doctors can only accurate diagnose from what you tell them and unfortunately our loved ones are not able to communicate those things. This site has people on it who have had every type and could be of some help to you. Good luck

Here is a way that scans can be more definitive in diagnosing alzheimers.

A new type of brain scan may help to detect Alzheimer’s early, using no radiation and at less cost than other techniques, researchers report. Doctors at the University of Pennsylvania’s Perelman School of Medicine have developed a form of magnetic resonance imaging, or MRI, that detects brain changes that signal Alzheimer’s disease. The doctors have developed a modification to the technique called arterial spin labeling, or ASL-MRI. Small studies show, this may be a useful way to diagnose probable early dementia.

MRI scans are routinely used in hospitals to check for tumors and other issues, and seniors with memory problems may undergo the procedure to rule out brain tumors, strokes or other problems that may be causing the deficits. If Alzheimer’s is suspected, they may then undergo another scanning procedure, such as a PET scan.

The advantage of the new ASL-MRI technique is that someone could undergo brain scanning in a single session to help determine whether Alzheimer’s may be present. The technique looks for changes in blood flow and the uptake of blood sugar, or glucose, in the memory centers of the brain. It requires about an additional 20 minutes compared to standard MRI scans.

“Increases or decreases in brain function are accompanied by changes in both blood flow and glucose metabolism,” explained Dr. John Detre, professor of Neurology and Radiology at Penn, who has worked on ASL-MRI for the past 20 years. “We designed ASL-MRI to allow cerebral blood flow to be imaged noninvasively and quantitatively using a routine MRI scanner.”

Studies show that the MRI method is similar in effectiveness to current PET scans that inject a radioactive dye to measure these brain changes. However, the ASL-MRI method uses no radiation and costs one-fourth as much.

“If ASL-MRI were included in the initial diagnostic work-up routinely, it would save the time for obtaining an additional PET scan, which we often will order when there is diagnostic uncertainty, and would potentially speed up diagnosis,” said Dr. David Wolk, Assistant Director of the Penn Memory Center and a collaborator on the research.

The studies compared the MRI technique and the specialized PET scan results using flurodeoxyglucose, or FDG, a radioactive tracer. In one, published in the journal Alzheimer’s and Dementia, doctors compared images from 13 patients diagnosed with Alzheimer’s and 18 age-matched controls. Both methods proved equally effective in detecting signs of early Alzheimer’s. In the second study, published in the journal Neurology, data from 15 AD patients were compared to 19 age-matched healthy adults. The patterns of reduction in cerebral blood flow were nearly identical to the patterns of reduced glucose metabolism by the PET scan and showed reductions in brain gray matter typical of Alzheimer’s disease.

“Given that ASL-MRI is entirely noninvasive, has no radiation exposure, is widely available and easily incorporated into standard MRI routines, it is potentially more suitable for screening and longitudinal disease tracking than FDG-PET,” said the Neurology study authors.

I have to agree with Salisbury since unfortunately the result may be futile. My mom definitely has dementia. I don't know the form but ruled out the other things mentioned. Our focus is on how to deal with it and the depression that accompanies the dementia. So far meds have had an adverse affect not to say it doesn't help others.

Alzheimer's Disease is one of many dementias. He checked symptoms and did some tests that gave him an idea. Unfortuanately, you can only tell exactly which form after death, with a brain autopsy. On this site, and on the Alz.org site are checklists of symptoms and definitions of the various stages of what you might expect. Know that every person travels their own path and there's no way to know exactly what is going to happen or even when or if.

Alzheimer's is like your brain is a puzzel and peices disappear slowly never to return leaving holes and dementia is like the puzzle peices of the brain all get mix up the electors miss fire I am sure I have that.mixed up but both can be upsetting and dangrouse to the person with it

Some of the behaviors and missing skills that the neurologist looks for are impaired judgment and decision-making skills, lack of interest in formerly enjoyable events and activities,and changes in personality. Short term menory loss, general depression and advanced age are often first diagnosed as "some sort of dementia."