Routine Blood Work for a 16-Year-Old Physical
For a routine physical examination in a healthy 16-year-old adolescent, no routine blood work is universally recommended by major pediatric guidelines. Screening laboratory tests should be targeted based on risk factors, symptoms, or specific clinical concerns rather than performed universally.
Risk-Based Screening Approach
When Blood Work IS Indicated
Targeted screening should be performed based on individual risk factors:
Lipid screening: Recommended for adolescents with family history of premature cardiovascular disease, obesity (BMI ≥95th percentile), diabetes, hypertension, or smoking 1
Hemoglobin/anemia screening: Consider for menstruating females with heavy periods, dietary restrictions (vegetarian/vegan), or symptoms of anemia (fatigue, pallor) 2, 3
Diabetes screening (fasting glucose or HbA1c): Indicated for adolescents with obesity (BMI ≥85th percentile) plus additional risk factors including family history of type 2 diabetes, signs of insulin resistance, or high-risk ethnicity 4
STI screening: Sexually active adolescents should be screened for HIV, chlamydia, and gonorrhea based on sexual history 1
Tuberculosis screening: For high-risk populations including recent immigrants, homeless youth, or those with known TB exposure 1
When Blood Work is NOT Routinely Indicated
For asymptomatic, healthy adolescents without risk factors, routine screening labs are not recommended:
Complete blood count (CBC): Not recommended as universal screening in healthy adolescents, despite being a commonly ordered test 5, 6, 2
Comprehensive metabolic panel: Not indicated without specific clinical concerns 4
Thyroid function tests: Only if symptoms of thyroid dysfunction are present 1
Liver or kidney function tests: Not part of routine screening in healthy adolescents 7
Clinical Considerations
The physical examination itself should focus on:
- Blood pressure measurement (should be <120/80 mmHg for adolescents ≥13 years) 1
- BMI calculation and growth trajectory assessment 1
- Skin examination for concerning lesions 7
- Assessment for signs of substance use, depression, or eating disorders 1
Common Pitfalls to Avoid
Avoid ordering "routine" labs without clinical indication - this leads to unnecessary costs, false positives requiring additional workup, and patient anxiety 6, 4
Don't miss targeted screening opportunities - while universal screening isn't recommended, failing to screen high-risk adolescents (obese teens for diabetes, sexually active teens for STIs) represents a missed prevention opportunity 1, 4
Ensure confidential discussion - adolescents may not disclose sexual activity or substance use with parents present, which could lead to missed screening opportunities 1