Use familial AD genetics, AD biomarkers, and episodic memory changes in Alzheimer disease to frame the working diagnosis and next step; use it to sharpen the differential and avoid a false label. Make AD biomarkers the checkpoint that determines whether you escalate testing, narrow the differential, or change treatment.

Inherited, familial cases are actually quite rare, accounting for fewer than 7% of all Alzheimer's diagnoses; Additionally, testing for phosphorylated tau in blood plasma, such as p-tau 181 or p-tau 217, correlates beautifully with true Alzheimer's pathology in the brain; Episodic memory is our ability to recall specific personal events or life episodes tied to a particular time and place; Clinicians can look at a few highly accurate biomarkers, including the amyloid beta 42-to-40 ratio, phosphorylated tau, and neurofilament light chain in the cerebrospinal fluid; When it is familial, the typical culprits are mutations in presenilin-one on chromosome 14, presenilin-two on chromosome 1, or the APP gene on chromosome 21