Use of the Laboratory in the Diagnostic Workup of Older Adults: Introduction | Serologic Tests | Hematologic Tests | Chemistry Tests | Serologic Tests for Syphilis | Human Immunodeficiency Virus Testing | Thyroid Function Tests | Vitamin B12, Folate, and Homocysteine | Toxicology | Urinalysis | Cerebrospinal Fluid Analysis | Electrocardiogram | Imaging Studies | Electroencephalography | Genetic Testing | Future Directions | Key Points | References | Suggested Readings
Laboratory testing is an essential component
of the psychiatric evaluation of elderly individuals, who often
present with comorbid medical illnesses. The laboratory does not
replace the clinician; there is no test that is pathognomonic for
a primary psychiatric illness. However, laboratory testing does
aid in the evaluation of comorbidities that complicate or contribute to
a psychiatric diagnosis.