What primary care lab tests are recommended for a 19-year-old?

Recommended Primary Care Laboratory Tests for a 19-Year-Old

For a 19-year-old patient, the recommended primary care laboratory tests should include HIV screening, sexually transmitted infection (STI) testing, and lipid screening based on risk factors, while routine comprehensive metabolic panels and complete blood counts are not universally recommended without specific indications.

Core Screening Tests

• HIV Testing: All patients aged 13-64 years should be screened routinely for HIV infection regardless of risk factors, with repeat screening at least annually for those at high risk (injection drug users, those who exchange sex for money/drugs, partners of HIV-infected persons, and those with multiple sex partners) 1

• Hepatitis C Screening: One-time testing for hepatitis C (HCV) is recommended for individuals with risk factors such as injection drug use 1

• Sexually Transmitted Infection (STI) Screening:

  • Screening for syphilis, gonorrhea, and chlamydia is recommended annually for sexually active individuals at risk for STIs 1
  • More frequent testing may be indicated for patients at higher risk of STIs 1

• Lipid Screening: The USPSTF concludes that evidence is insufficient to determine the balance of benefits and harms of screening for lipid disorders in asymptomatic individuals 20 years or younger 1

  • Familial hypercholesterolemia is associated with premature cardiovascular events in adulthood, but routine screening in adolescents has not been definitively shown to improve outcomes 1

Immunization Considerations

• HPV Vaccination: For those not previously vaccinated, HPV vaccine should be offered to females aged 11-26 years and males aged 11-21 years (up to age 26 for men who have sex with men or immunocompromised individuals) 1

• Hepatitis B Vaccination: Should be offered to all unvaccinated individuals under age 19 and all adults who are unvaccinated and have no documented history of hepatitis B infection 1

Tests Based on Risk Factors and Symptoms

• Complete Blood Count (CBC): Not routinely recommended for asymptomatic 19-year-olds without specific indications 2, 3

  • Consider CBC when evaluating symptoms such as fatigue, unexplained weight loss, or signs of infection 2

• Comprehensive Metabolic Panel (CMP): Not routinely recommended for asymptomatic 19-year-olds without specific indications 4

  • Consider when evaluating specific symptoms or monitoring certain medications

• Fasting Blood Glucose or Hemoglobin A1C: Consider for patients with risk factors for diabetes such as obesity, family history, or certain ethnic backgrounds 4

• Urinalysis: Not routinely recommended unless symptoms of urinary tract infection are present or for monitoring specific conditions 4

Common Pitfalls to Avoid

• Overscreening: Ordering comprehensive panels without specific indications can lead to unnecessary follow-up testing, increased costs, and patient anxiety from false positive results 2, 5

• Underscreening for STIs: Failing to screen sexually active young adults for STIs can miss opportunities for early treatment and prevention of transmission 1

• Missing HIV screening: The CDC recommends universal HIV screening for all patients aged 13-64, regardless of perceived risk factors 1

• Inconsistent follow-up: Ensuring that abnormal results are properly communicated and followed up is essential, particularly for STI and HIV testing 1

Special Considerations

• Cervical Cancer Screening: For females, cervical cancer screening should begin at age 21 regardless of sexual history, not at age 19 1

• Mental Health Screening: Consider depression and anxiety screening as part of routine primary care for young adults 4

• Substance Use Assessment: Consider screening for alcohol, tobacco, and drug use as part of routine primary care for this age group 4