Mastitis Flashcards
definition of mastitis
infection of the mammary duct often associated with lactation (usually staph aureus)
mastitis is inflammation of the breast parenchyma with or without infection
- Mastitis with infection may be lactational (puerperal) or non-lactational (e.g., duct ectasia).
- Non-infectious mastitis includes idiopathic granulomatous inflammation and other inflammatory conditions (e.g., foreign body reaction).
definition of breast abscess
breast abscess is the main complication of mastitis . localised area of infection with a walled of collection of pus - may or may not be associated with mastitis
aetiology of mastitis
lactational - staphtlococcus aureus (most common)
nonpuerperal: S. aureus and anaerobes, often enterococci or bacteroides spp. (TB and actinomycosis are extremely rare causes).
other pathogens eg E Coli/streptococcus are rare
most frequently in women with nipple fissures (may come from issues with breast feeding technique), prolonged breast engorgement (eg from over production of milk or insufficient milk drainage eg infrequent feeding, quick weening, illness in either the baby or mother)
bacteria in nostril or throat of infant or on mother’s skin enters milk ducts during feeding - pathogen flourishes in stagnant milk = tissue inflammation
RF for mastitis
female
>30yrs
poor breastfeeding technique
lactation
milk stasis - may result from inadequate drainage, blocked ducts, milk oversupply, external pressure on the breast (e.g., tight-fitting bra), infrequent feeding, or rapid weaning
nipple injury
previous mastitis
prolongued mastitis - abscess
prior abscess
shaving or plucking areola hair - may cause a Montgomery follicle abscess with potential for more widespread infection
anatomical breast defect, mammoplasty or scar - Altered duct structure may interfere with milk flow and predispose to mastitis.
other underlying breast condition
nipple piercing
foreign body - Silicone mastitis may cause a hard, tender, erythematous breast mass
skin infection - Dermatoses, such as psoriasis or eczema, may cause nipple fissures that result in recurrent mastitis.
staph aureus carrier
immunosuppression
smoking
associated with wound infections after breast surgery, diabetes and steroid therapy
pathology of mastitis
frequently loculated
nonpuerperal arise in periareolar tissues and are a manifestation of duct ectasia/periductal mastitis
epidemiology of mastitis
incidence of up to 10% of nursing mothers - particularly 2-4 weeks postpartum
occur soon after starting breast feeding and on weening - incomplete emptying of breast = stasis and engorgement
more commonly affect women 15-45yrs - especially those breastfeeding
non-lactational more common 30-60yrs and smokers
sx of mastitis
painful, hot, swelling, tender, firm, erythematous breast - usually unilateral
pain during breast feeding
reduced milk secretion
flu-like symptoms - malaise, fever, chills
sx of breast abscess
breast pain - Usually sharp, shooting, or throbbing breast pain, especially with breastfeeding
erythema
oedema
purulent discharge from nipple of infected breast
fever
nausea
decreased milk outflow
breast warmth
tenderness
firmness
swelling - Swelling may indicate skin oedema and/or underlying abscess formation.
flu like symtpoms - malaise and myalgia, fever
Lactational mastitis tends to involve more peripheral wedge-shaped areas.
Women with a nonpuerperal abscess often have a history of previous infections and systemic upset is less pronounced.
signs of mastitis
reactive lymphadenopathy in some cases
signs of abscess breast
fluctuating mass on palpation
area of breast is swollen, warm, tender overlying skin is inflammed
nipple may have cracks/fissures
In non-puerperal cases there may be evidence of scars or tissue distortion from previous episodes, or signs of duct ectasia, e.g. nipple retraction.
pyrexia/tachycardia
Ix for mastitis
clinical diagnosis
breast milk cultures of imaging may be required if no response to initial treatment
Ix for abscess
US
microscopy, culture and sensitivity of pus samples
Mx for mastitis
in nursing mothers - frequent emptying of the breast - breast feeding with alternate breasts recommended every 2-3 hrs
analgesics (ibuprofen)
cold compresses
AB - oral penicillinase-resistant penicillin or cephalosporin (e.g., dicloxacillin or cephalexin)
In the case of methicillin-resistant Staphylococcus aureus (MRSA): clindamycin or trimethoprim-sulfamethoxazole (TMP-SMX)
In the case of inadequate response to initial treatment:
Initiate treatment according to breast milk culture results.
Consider an underlying breast abscess, which requires surgical drainage.
medical mx for abscess
early, cellulitic phase - AB
flucloxacillinin the case of lactational, with the addition of metronidazole in non puerperal abscesses
surgical mx for abscess
lactational
- daily needle aspiration with AB may be successful
- in most cases - formal incision and drainage
- should allow full drainage and be cosmetic
- loculi are explored and broken down with finger
- wound may be packed lightly with antiseptic soaked kaltostat and left open with daily packing, or primary closure performed with AB cover
- breast feeding should continue on non-affected side
- affected side should be emptied with pump/manually
non-puerperal
- open drainage avoided, or carried out through a small incision
- definitive treatment should be carried out once infection settled by excision of duct system
