This can happen from one or both breasts. It may be from a single duct opening or from multiple duct openings. The color of the discharge may be transparent or watery, bloody, blackish or greenish. It may also be purulent or like pus.
The single most important examination finding in this situation is to look for an associated lump as that can signal the presence of a malignancy. If there is no associated lump, mammography will help us to identify one if it is present. A cytology of the duct discharge may help to look for any malignant cells but it is not always diagnostic.
Serous or watery discharge from multiple duct openings in a multiparous woman may be physiological and does not require any treatment.
Purulent discharge with an underlying painful lump may be due to duct ectasia with abscess formation. The patient here requires antibiotic cover and may require surgery.
Bloody or blackish discharge may be seen in case of malignancy, intraductal papilloma or with duct ectasia. If mammography is inconclusive, the patient should undergo a procedure known as microdochectomy, in which the entire affected duct system is cored out and excised. This gives us the histopathology of the cause of the discharge as well as taking care of the problem by stopping the further discharge.