According to the NIH, all patients with new onset of dementia should have several basic and standard diagnostic studies, with modifications to be made according to individual circumstances:
Complete blood count.
Screening metabolic panel.
Thyroid function tests.
Vitamin B-12 and folate levels.
Tests for syphilis and, depending on history, for human immunodeficiency antibodies.
Most of the readily reversible metabolic, endocrine, deficiency, and infectious states, whether causative or complicating, will be revealed by these simple investigations when combined with history and physical examination.