What is the workup for a 22-year-old female with spontaneous milky nipple discharge and shooting, tingling pain, with a previously normal prolactin level?

Workup for 22-Year-Old Female with Spontaneous Milky Nipple Discharge

Start with breast ultrasound as the initial imaging modality, and repeat serum prolactin level along with TSH and renal function tests to evaluate for galactorrhea, even though prolactin was normal 6 months ago. 1, 2, 3

Clinical Characterization

This presentation requires careful distinction between physiologic galactorrhea versus pathologic discharge:

• Milky discharge is typically physiologic (galactorrhea) and bilateral from multiple ducts, though it can occasionally be unilateral 1, 4
• However, spontaneous discharge (occurring without expression) is a pathologic feature that warrants full evaluation regardless of color 2, 4
• The shooting, tingling pain is non-specific but may suggest hormonal etiology or ductal pathology 5

The key question is whether this is truly spontaneous or requires minimal provocation - if it only occurs with manipulation, this favors physiologic galactorrhea and requires different workup 1

Laboratory Workup

Repeat prolactin level now, as hyperprolactinemia can develop over 6 months and is the most common cause of galactorrhea: 3

• Serum prolactin (repeat despite prior normal result 6 months ago)
• TSH (hypothyroidism causes 10-15% of galactorrhea cases) 3
• Pregnancy test (mandatory in premenopausal women) 3
• Renal function tests (chronic renal failure can cause hyperprolactinemia) 3
• Medication review for dopamine antagonists, antipsychotics, SSRIs, antihypertensives 3

Imaging Algorithm

For a 22-year-old woman, ultrasound is the appropriate initial imaging modality: 1, 2

• Breast ultrasound with focused retroareolar imaging is rated 9/9 (usually appropriate) as the initial examination for women under 30 years 1
• Use special techniques including peripheral compression, 2-hand compression, and rolled-nipple techniques for optimal retroareolar visualization 1
• Mammography is rated only 5/9 (may be appropriate) in this age group and should be added only if ultrasound shows suspicious findings or if patient has BRCA mutation or strong family history 1

Management Based on Results

If prolactin is elevated:

• Obtain pituitary MRI to evaluate for prolactinoma 3
• Discontinue causative medications if identified 3
• Consider cabergoline as first-line treatment for symptomatic hyperprolactinemia 3

If prolactin and imaging are normal:

• No further imaging is needed if discharge is truly physiologic (bilateral, multiple ducts, provoked only) 1, 4
• Reassurance and clinical follow-up are appropriate 5

If imaging shows suspicious lesion:

• Image-guided core biopsy (preferred over FNA) for tissue diagnosis 2

If discharge is truly spontaneous and unilateral despite normal workup:

• Consider breast MRI with contrast (though rated 1/9 as initial test, it may be appropriate after negative standard workup) 1, 2, 6
• Referral to breast surgeon for possible duct excision if discharge persists and is bothersome 4, 5

Critical Pitfalls to Avoid

• Do not assume prior normal prolactin excludes hyperprolactinemia - endocrine conditions and medication effects can develop over months 3
• Do not perform mammography as initial test in women under 30 unless ultrasound shows suspicious findings 1
• Distinguish spontaneous from provoked discharge - this fundamentally changes the evaluation pathway 1, 2
• Malignancy risk is only 3% in women under 40 years with pathologic discharge, so aggressive surgical intervention is not warranted without imaging abnormality 2, 4