The fluid that leaks from one or both nipples of a non-pregnant and non-breastfeeding breast is called a nipple discharge. Nipple discharge is a complex diagnostic challenge for the clinician partly because of it could be the manifestation of a wide variety of diseases and clinical conditions.
Each human breast has 15 to 20 milk ducts. A discharge can come from one or more of these milk ducts.
The most important consideration in a patient with nipple discharge for both the patient and the physician is the possible association of this condition with an underlying breast cancer. With the increased public awareness of breast cancer, an increasing number of women are asking their health care providers about nipple discharge. Thus, a clinician must be aware and knowledgeable in evaluating nipple discharge.
Nipple discharge is not an uncommon complaint in the emergency department and can be benign (physiologic discharge) or a sign of a pathologic process.
Nipple discharge is normal during last weeks of pregnancy, after the childbirth and during the breastfeeding period. It can also be normal in women who are not pregnant and are not breastfeeding, especially during reproductive years. Certain manipulations of the breasts, such as fondling, sucking, or massaging can stimulate milk ducts to secrete fluid. Stress also has been shown to cause nipple discharge.
All postmenopausal nipple discharge, however, is significant and requires further evaluation. Nipple discharge in men is always abnormal and also must prompt an evaluation.
The majority of all nipple discharges are benign in etiology (97%).
Causes of physiologic nipple discharge:
Causes of pathologic nipple discharge:
Nipple discharge is the third most common breast complaint after breast pain and breast mass. Fifty percent to 80% of women in their reproductive years had a nipple discharge, and 6.8% of these were referred to a breast surgeon. Most nipple discharge is benign in origin (97%).
The clinical history is most helpful in distinguishing benign from suspicious or pathologic nipple discharge. Patient's age is very important, as women older than 40 years old are at higher risk of having pathologic causes of the nipple discharge. Post-menopausal women with nipple discharge rarely have a benign cause of their symptom.
History of present illness should include the onset of discharge, association with the menstrual cycle, persistence, and the character and color of the discharge.
A patient's reproductive history is important (e.g., the age at menarche, age at menopause, and a history of pregnancies including age at first full-term pregnancy).
Obtain a history of any breast problems, including breast biopsies.
Obtain a surgical history (e.g., hysterectomy and whether ovaries were removed). In premenopausal women, obtain the pregnancies/births history, history of breastfeeding, use of oral contraception or hormonal replacement therapy (HRT).
Family history should contain information about cancers, especially of breast/ovaries, and menopausal status of close relatives.
Medications history is of paramount importance, as many medications can cause nipple discharge as a side effect.
In the review of systems, a physician should ask for the presence of fever (mastitis or breast abscess), symptoms of hypothyroidism (weight gain, cold intolerance, constipation, etc.amenorhea), symptoms of liver disease (ascites, jaundice), symptoms of pituitary tumor (visual amenorrhea, headache).
On physical examination, the physician should examine the patient for the presence of any breast masses, asymmetries, and skin changes. After the inspection, palpation should include all four quadrants of each breast and bilateral axillae, supra- and infraclavicular areas to look for masses, swelling, tenderness, lymphadenopathy. If no spontaneous discharge is visible, the examiner should attempt to extract the discharge by applying even pressure from the periphery toward the nipples (so-called, pressure point exam).
Physiologic discharge is usually bilateral, require manual extraction, fluid is clear, cloudy, white, yellow, green, or brown, involves multiple ducts, and is non-sticky. Pathologic discharge is usually unilateral, spontaneous, varies in appearance, and depending on the cause, involves a single duct. Abnormal discharge is frequently associated with other abnormalities, such as a mass, swelling, redness, dimpled skin, or retracted nipple.
The primary goal of evaluation of the nipple discharge in a general outpatient setting or the emergency department is to distinguish patients with benign discharge from those with underlying breast cancer, infection/abscess, or those patients who are at high risk of developing pathologic processes. Those patients, whose age, history and physical examination suggest the benign cause of their discharge, may be reassured and discharged with outpatient follow-up at their primary care provider's office. However, in patients at high risk for a pathologic process as a cause of their discharge or with worrisome history and physical examination, urgent follow-up with a breast surgeon must be sought.
The exception is a suspected or obvious breast abscess when emergent ultrasound of the breast and a general surgery consultation are needed in the emergency department. Depending on the results of the breast ultrasound and evaluation of the general surgery consultants, the patient may or may not be taken to the operating room for incision and drainage of an abscess. Incision and drainage of a breast abscess in the emergency department are discouraged due to the high pain sensitivity and aesthetic significance of the area, especially when abscess involves areola/nipple area. Therefore, appropriate anesthesia is needed, possibly in the operating room, to minimize pain and suffering in a patient, as well, as aesthetic considerations.
It is important to recognize that an emergency physician has a significant yet particular role in evaluating nipple discharge. An emergency department physician must recognize his or her limitations in detailed evaluation of suspected breast cancer and must emphasize to a patient the absolute need for seeking an appropriate breast specialist for further evaluation, diagnostic testing, and/or treatment. There is no role for an emergency department physician in the treatment of the pathologic nipple discharge, as this is beyond his or her scope of practice.