What blood work is recommended for a nonpregnant female with breast discharge?

Blood Work for Nonpregnant 35-Year-Old Female with Breast Discharge

For a nonpregnant 35-year-old female with breast discharge, serum prolactin level is the recommended initial blood test to rule out hyperprolactinemia, followed by thyroid-stimulating hormone (TSH) if prolactin is elevated. 1

Initial Assessment of Breast Discharge

Characterize the Discharge

• Determine if discharge is:
  • Physiologic (bilateral, multiple ducts, white/green/yellow, provoked) 1
  • Pathologic (spontaneous, single duct, unilateral, clear/serous/serosanguineous/bloody) 1

Blood Work Algorithm

1. Serum Prolactin Level:

   • Primary initial blood test for all patients with pathologic nipple discharge 1
   • Elevated levels may indicate:
     • Pituitary microadenoma
     • Medication effect
     • Hypothyroidism
     • Chronic renal failure
     • Cirrhosis

2. If Prolactin is Elevated:

   • Thyroid-Stimulating Hormone (TSH) to rule out hypothyroidism 1
   • Renal Function Tests (BUN, creatinine) if clinically indicated 1
   • Medication review for agents that can cause hyperprolactinemia:
     • Psychoactive drugs
     • Antihypertensive medications
     • Opiates
     • Oral contraceptives
     • Estrogen 1

Imaging Recommendations

After appropriate blood work, imaging is essential for complete evaluation:

• For a 35-year-old female: Both mammography/digital breast tomosynthesis and ultrasound are rated as "usually appropriate" (9/9) by the American College of Radiology 2, 1
• Either mammogram or ultrasound can be used as the initial imaging modality for women 30-39 years 1

Important Clinical Considerations

Risk Assessment

• Pathologic nipple discharge carries a 5-21% risk of underlying malignancy 1
• Risk factors increasing likelihood of malignancy:
  • Bloody or watery discharge
  • Unilateral discharge from a single duct
  • Presence of a palpable mass
  • Age over 50 years 1, 3

Common Pitfalls to Avoid

• Don't dismiss clear fluid discharge as benign without thorough evaluation, even with normal imaging 1
• Don't rely solely on cytology of nipple discharge, as negative results should not stop further evaluation 1
• Don't miss medication-induced causes of nipple discharge 1

Follow-up Recommendations

• If blood work is normal but discharge persists, proceed with recommended imaging 1
• If imaging is negative but discharge continues, further evaluation with MRI breast or ductography may be warranted 1
• Tissue biopsy with core needle biopsy is preferred if imaging identifies suspicious findings 1

Remember that while most nipple discharge is benign (intraductal papilloma being the most common cause), a systematic approach beginning with appropriate blood work is essential to rule out serious underlying conditions that may affect morbidity and mortality 4, 3.