- Subareolar
- Intramammary
- Retromammary (submammary)
Anatomy of the Breast
Blood supply- Anterior intercostal artery – branch of internal thoracic a
- Lateral thoracic and thoracoacromial a – branch of axillary a
- Posterior intercostal a – branch form thoracic aorta
Subareolar mastitis
- Infection under the areola – due to cracks in nipple
- Results from infected gland of Montgomery
- Associated with duct ectasia – causes formation of abscess, sinus, fistula
- Common in nonlactating women
Clinical features
-
- Red, inflamed, oedematous areola with tender swelling underneath
- Nipple retraction
Differential diagnosis – Paget’s disease of the nipple
Treatment – pus drained under antibiotics through subareolar incision
Intramammary mastitis
Lactational abscess of the breast – seen in lactating women
- Precipitating factors
- Cracked/retracted nipple
- Improper cleaning of the nipple
- Inadequate milk suckling by baby
- Infection from the mouth of the baby
- Mode of infection – initially infection is localised but eventually involves the whole breast
- Bacteria (S.aureus) enters breast during sucking through cracked nipple
- S.aureus causes clotting of milk in the blocked duct and multiply
- Duct gets blocked by epithelial debris or retracted nipple
- Clinical features
- Continuous throbbing pain and high fever
- Diffuse redness, tenderness, warmness, brawny induration
- Purulent discharged from nipple
- Differential diagnosis – inflammatory ca of breast
- Treatment
- Antibiotics – cephalosporins, flucloxacillin
- Bromocriptine (dopamine agonist) – stops lactation by suppressing prolactin
- Repeated US guided aspiration
- Drainage under general anaesthesia – if mastitis doesn’t resolve with antibiotics in 48 hours
- Complications
- Antibioma formation – nontender, hard breast lump with sterile pus inside
- Sinus formation, skin necrosis, fistula
- Recurrent infection, bacteraemia, septicaemia
Nonlactational abscess of the breast
- Occurs in duct ectasia and periareolar infections
- Organisms – bacteroides, anaerobic streptococci, enterococci
- Recurrent with tender swelling under the areola
- Treatment – antibiotics, aspiration, drainage, excision
Retromammary mastitis
- Due to tuberculosis of intercostals lymph nodes/ribs or suppuration of the intercostals lymph nodes
- Breast is normal
- Investigations
- CXR, FNAC, ESR
- US of breast and chest wall
- CT chest
- Treatment – treat cause; drainage through submammary/retromammary incision
Antibioma
- If intramammary mastitis is not drained but only treated by ABs, pus localises and becomes sterile with a thick fibrous tissue cover
- Clinical features
- Previous history of mastitis treated with ABs
- Painless swelling, smooth, nontender, hard, fixed to breast tissue
- Investigations – FNAC, mammography, US breast
- Treatment – excision and later ABs
Duct ectasia
- Dilation of lactiferous ducts due to muscular relaxation of duct wall with periductal mastitis
- ‘plasma cell mastitis’
- Commonly many ducts involved