Diagnosis
To diagnose primary progressive aphasia, your doctor will review your symptoms and order tests.
Worsening communication difficulty without significant changes in thinking and behavior for a year or two is a hallmark of primary progressive aphasia.
Neurological examination
Doctors might conduct a neurological examination as well as a speech-language evaluation and a neuropsychological evaluation. Tests will measure your speech, language comprehension and skills, recognition and naming of objects, recall, and other factors.
Blood tests
Doctors might order blood tests to check for infections, measure medication levels or look for other medical conditions. Genetic tests can determine if you have genetic mutations associated with primary progressive aphasia or other neurological conditions.
Brain scans
MRI scans can help diagnose primary progressive aphasia, detect shrinking of certain areas of the brain and show which area of the brain might be affected. MRI scans can also detect strokes, tumors or other conditions that affect brain function.
Single-photon emission computerized tomography or PET scans can show blood flow or glucose metabolism abnormalities in areas of your brain.
Source: http://www.mayoclinic.com