Nipple Discharge

Nipple discharge has a number of disparate causes, from the first outward sign of a previously unrecognised pregnancy, to a late sign of an advanced carcinoma. It can cause embarrassment and concern in equally large amounts. Compared with breast pain and lumps, it is a relatively rare presenting symptom. Take it seriously and assess carefully – investigation will often be needed.

Published: 2nd August 2022 | Updated: 15th August 2022

Differential diagnosis

Common Diagnoses

  • Pregnancy
  • Duct Papilloma
  • Duct Ectasia
  • Acute Mastitis/Breast Abscess
  • Areolar Abscess (Infected Gland of Montgomery)

Occasional Diagnoses

  • Oral Contraceptives
  • Intraduct Carcinoma
  • Neonatal and Peripubertal Galactorrhoea (Also Post-Lactation)
  • Hyperprolactinaemia (Drugs, Prolactinoma, Hypothyroidism)
  • Duct Epithelial Proliferation
  • Galactocoele

Rare Diagnoses

  • Periductal (Plasma Cell) Mastitis
  • Mechanical Stimulation
  • Invasive Carcinoma
  • Tuberculous Abscess
  • Mamillary Duct Fistula
  • Paget’s Disease of Nipple
  • Comedo Mastitis

Ready reckoner

Key distinguishing features of the most common diagnoses

Pregnancy PapillomaEctasiaMastitisAreolar Abscess
Hot Tender SegmentNoNoNoYesYes

Possible investigations

Likely: None (referral for specialist assessment in suspicious cases)

Possible: Pregnancy test, prolactin level, TFT

Small Print: Swab of purulent discharge.

  • Pregnancy test if pregnancy suspected
  • Swab purulent discharge: May help guide antibiotic therapy
  • Prolactin level and TFT: To check for hyperprolactinaemia or hypothyroidism in galactorrhoea.
  • Excision biopsy will be performed if a suspicious lump is palpable. In cases of doubt, mammography may help; surgical exploration may also be undertaken if pressure on an area of one breast consistently elicits discharge.

Top Tips

  • Women presenting with breast discharge are likely to be afraid there may be an underlying cancer. To ‘reassure’ properly, make sure you address this anxiety.
  • If the discharge is bilateral, then serious breast disease is highly unlikely.
  • In a woman of child-bearing age with bilateral serous discharge, enquire specifically about pregnancy – this possibility may be deliberately concealed or genuinely overlooked by the patient.
  • If a pre-menopausal woman is amenorrhoeic with bilateral discharge and pregnancy has been excluded, remember the possibility of hyperprolactinaemia.

Red Flags

  • Refer urgently any patient aged 50 or more with a unilateral discharge, retraction or other nipple symptoms of concern.
  • If a lump is palpable, or pressure on a certain area of the breast consistently produces the discharge, refer for probable excision biopsy.
  • Bright red blood from one nipple is usually caused by duct papilloma or ectasia – but can be caused by carcinoma and therefore requires prompt referral.
  • Nipple discharge in a male is always abnormal, except occasionally in pubertal boys. Investigate or refer as appropriate
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Website disclaimer

Pulse Reference is based on the best-selling book Symptom Sorter.

The experts behind Pulse Reference are Dr Keith Hopcroft who is the co-author of Symptom Sorter, a GP in Essex and Pulse’s editorial advisor and Dr Poppy Freeman, a GP in Camden and also a clinical advisor to Pulse.

This website is for clinical guidance only and cannot give definitive diagnostic information. Practitioners should work within the limits of their individual professional practice, seek guidance when necessary and refer appropriately.