MASTITIS AND BREAST ABSCESS

Mastitis can be divided into lactational and nonlactational. While infection is the primary reason for lactational mastitis non-infectious causes predominate the latter.

Lactational Mastitis:
This type is also referred to as puerperal sepsis and occurs commonly after first pregnancy. They are commonly divided into two types first type occurs usually within 2 or 3 days postpartum. This type of infection is commonly thought to result from hospital acquired infection. Infection is transmitted from infant to infant and subsequently to mother by means of retrograde transmission through the ductal system. Staphylococcus is the common organism.

The second type occurs after 2 or 3 weeks after nursing and is not thought to be hospital acquired. The organism is staphylococcus aureus, epidermidis and streptococcal species.

Pathogenesis:
The microorganisms enter the breast through three ways.
1. Retrograde through a lactiferous duct or a cracked nipple. (Commonest)
2. Through lymphatic
3. By haematogenous spread.
During early feeding some mothers experience attachment difficulties, which predispose to nipple trauma, providing a portal of entry for infectious agents.
There is also often associated milk stasis resulting from erratic feeding pattern, switching to second breast before the first has drained, poor positioning, blocked ducts or an abundant milk secretion. In these cases when milk is not sufficiently drained engorgement can cause increased pressure, leakage of milk components into the breast parenchyma resulting in inflammatory response. Persistent milk stasis also provides for bacterial infection.

Symptoms:
Patients often present with an inflamed oedematous, erythematous tender area of the breast. This localised process is often accompanied by a sudden onset of systemic symptoms such as fever and flu like symptoms.

Management:
In most occasions the mastitis is treated with a course of antibiotics, which covers penicillanase resistant organisms. The other supportive measures such as rest, increased fluid intake hot compresses analgesics and anti inflammatories are recommended.

Patients are often advised to continue breast-feeding in order to promote drainage of the breast unless they drain frank pus or infected with human immuodeficiency virus as in the latter case viral load may increase the mother-to- child transmission rate.

All infections should be followed clinically as well as ultrasonographically till completely resolved. Interval of assessment will vary in individual patients.

Non lactational Mastitis:

Non lactational mastitis can take several forms caused by either infectious or inflammatory processes.
Inflammatory processes include periareolar mastitis, Peripheral infections including granulomatous mastitis, fibrocystic change, associated with diabetes, rheumatoid arthritis, steroid treatment,
Infectious process includes rare infections like TB, fungal infections which will not be dealt in detail.
Primary infections of skin due to infected sebaceous cyst and hidradenitis suppurativa are not uncommon and should be treated appropriately as any where else in body.

Periareolar mastitis:
This is the most common mastitis occurring outside the puerperal period. It is a clinical syndrome comprising noncyclical mastalgia, nipple discharge, nipple retraction, and sub areolar breast lump that may accompanied by inflammation of the overlying skin, abscess and mammary fistulae. Current evidence links this condition to smoking and both aerobic and anaerobic organisms have been isolated. This condition is also termed as periductal mastitis
The patho physiology is often controversial. One theory is that duct dilatation is the inciting event causing inflammation and leakage of duct contents through he wall. The other theory is that inflammation is the initiating event resulting in dilatation of the duct.
The treatment is primarily nonsurgical and is aimed at presenting complaint. Imaging in the form of Mammogram or ultrasound may be needle followed by FNAC. Antibiotics may be necessary. Patients are strongly advised to give up smoking to prevent further episodes.
If there is mammary fistula then it requires surgical excision.

Peripheral infections:
They often present as extra areolar lump in young parous women. They may be attached to skin. The aetiology is often unknown and the aspiration may provide diagnosis. 50% of patients will have uneventful recovery and the rest will go on to have abscesses, fistulae and chronic suppuration, which may need surgery.

Fibrocystic change in breast tissue is extremely common and can clinically resemble mastitis. Patient often presents with breast tenderness and a well-defined area of erythema. Mammography and ultrasound maybe needed and may not detect any abnormality. The symptoms may resolve spontaneously and require no treatment. Sometimes rupture of cyst can present this way with resolution of symptoms in few days.

Breast Abscess:

Again the breast abscess can arise during either lactation or nonlactational period as a result of periductal mastitis.

Puerperal Breast abscess:
When the mastitis is not adequately controlled with antibiotics or the infection is resistant to antibiotics then it results in abscess. Patient may present with fever, tachycaria and leukocytes. The breast may be engorged, red and tender. They are often treated by ultra sound aspiration with antibiotic cover. Alternatively they may require open incision drainage.

Duct ectasia/Periductal mastitis Related abscess:
They affect often older women who smoke. The super added bacterial infection in periductal mastitis could present as abscess. They are often treated with aspiration rather than open drainage as they may lead to fistulae. The fistulae are treated by excision. They often tend to recur and may require excision of the involved ducts later.

Neonatal breast infections are most common in first few weeks of life when the breast bud is enlarged. Staphylococcus aureus is a common organism but Escherichia coli can also be the pathogen. Abscess if develops should be treated with formal drainage by placing the incision as peripherally as possible to avoid damage to breast bud.

Inflammatory condition and malignancy:
The clinicians should be aware of the possibility of inflammatory carcinoma, an aggressive form of breast cancer if they don't respond to standard treatments. The inflammatory carcinoma presents with rapid onset of symptoms with erythematous swollen painful breast and peau d' orange and skin thickening. Inflammatory mass without pus on multiple ultrasound examinations, which fails to decrease in size on antibiotics, should be fully investigated with tru-cut biopsies to exclude underlying carcinoma.

Click here to see Management Protocol

If you require further advice or information please contact the
Macmillan Breast Care Nurses, Hazel Ricard and Hilary Rickwood on 020 8565 5885