Laboratory Tests for Complete Physical Examination
For a complete physical exam in a patient with unknown medical history, order a comprehensive metabolic panel, complete blood count, lipid profile, hemoglobin A1c, thyroid-stimulating hormone, and urinalysis as your core screening battery.
Core Laboratory Panel
Essential Metabolic Assessment
- Comprehensive metabolic panel should include serum electrolytes (sodium, potassium, chloride), serum calcium, magnesium, liver function tests, serum creatinine with estimated glomerular filtration rate (eGFR), blood urea nitrogen, and glucose 1, 2, 3
- Fasting glucose or hemoglobin A1c is required to screen for diabetes and assess metabolic health 1, 2
- Serum creatinine with eGFR calculation is essential for assessing baseline renal function in all patients 1
Hematologic Screening
- Complete blood count (CBC) with differential is fundamental for detecting anemia, infections, hematologic abnormalities, and serves as a powerful diagnostic tool when combined with history and physical examination 2, 1, 4, 5
- The CBC evaluates red blood cells, white blood cells, platelets, and can predict risk for cardiovascular disease and metabolic conditions 5, 6
Cardiovascular and Metabolic Risk Assessment
- Lipid profile including LDL cholesterol is a Class I recommendation for metabolic screening and cardiovascular risk stratification 1
- This should be obtained as a fasting lipid panel when possible 7
Endocrine Screening
- Thyroid-stimulating hormone (TSH) should be measured routinely to rule out thyroid disorders that can present with diverse symptoms 2, 8
- Thyroid dysfunction is common and can affect multiple organ systems 2
Urinary Assessment
- Urinalysis is essential for detecting proteinuria, microalbuminuria (a key marker of organ damage), infections, and other renal abnormalities 1, 8, 4
- This provides critical information about kidney function and metabolic health 1
Age and Risk-Based Additions
Additional Tests for Specific Populations
- Hepatitis B testing (HBsAg and HBcAb) should be considered in patients from regions with high prevalence or those with risk factors such as blood transfusion history or intravenous drug use 2
- Vitamin B12 and folate levels should be checked if there are concerns about nutritional deficiencies affecting cognition or hematologic parameters 8
- HIV testing is recommended when risk factors are present 8
Inflammatory Markers (When Indicated)
- Erythrocyte sedimentation rate (ESR) or C-reactive protein can assess for inflammatory conditions when clinically suggested 2, 8
- These are not routine but should be added based on clinical presentation 2
Important Clinical Considerations
Common Pitfalls to Avoid
- Do not order tests in isolation—laboratory results must be interpreted in conjunction with history and physical examination findings 4, 3
- Electrolyte monitoring is critical because abnormalities in potassium, sodium, and calcium can cause serious complications and guide medication management 2, 3
- Renal function affects multiple medications—baseline creatinine and eGFR are essential for future drug dosing decisions 2, 1
Interpretation Nuances
- Hemoglobin A1c reflects average glucose control over 2-3 months and is more convenient than fasting glucose, though both are acceptable screening tools 1
- CBC abnormalities occur in 10-20% of tests and require structured evaluation to determine if subspecialty consultation is needed 6
- Comprehensive metabolic panels ordered as a single test are more efficient than ordering individual components 7