Mastitis/ breast abscess

Question 1

What is mastitis?

Answer 1

Inflammation of breast tissue
Lactational (Puerperal- most common) or non-lactational
+/- infection

Question 2

How does infection occur in mastitis?

Answer 2

Usually due to retrograde spread through lactiferous duct or traumatised nipple

Question 3

What is a breast abscess?

Answer 3

localised collection of pus within the breast
Lactational or non-lactational

Question 4

Describe the aetiology of puerperal mastitis

Answer 4

Milk stasis is most common cause
Accumulated milk causes an inflammatory response which may or may not progress to infection

Question 5

Describe aetiology of non-puerperal mastitis

Answer 5

mastitis is usually accompanied by infection, either central/ subareolar or peripheral.
May result from underlying duct ectasia or foreign material e.g. piercing

Question 6

What may mastitis lead to?

Answer 6

Abscess formation

Question 7

What are the most common causes of infectious mastitis?

Answer 7

Lactational: Staphylococcus aureus
Non-lactational: staphylococcus aureus or anaerobes

Question 8

List 3 risk factors for mastitis in lactating women

Answer 8

Milk stasis: poor infant attachment, reduced number/ duration of feeds, pressure on breast (tight clothing)
Age (21-35)
Non-lactational RFs

Question 9

List 7 risk factors for non-lactational mastitis

Answer 9

SMOKING
Nipple damage: piercings/ skin conditions e.g. eczema
Trauma to breast
Underlying breast abnormality
Immunosuppression
Shaving/ plucking aerola hair
Foreign materials in breast augmentation/ reconstruction

Question 10

List 4 risk factors for breast abscess

Answer 10

Previous mastitis/ breast abscess
Immunosuppression
S aureus carriage
Poor hygeine

Question 11

Describe the epidemiology of mastitis and breast abscesses

Answer 11

L: common infers 2-3w postpartum
NL: less common, tends to occur in 30-60y smokers

Question 12

Where do lactational vs non-lactational breast abscesses tend to occur?

Answer 12

L: peripheral, upper outer

NL: central/ sub-areolar/ lower quadrants

Question 13

List 4 S/S of mastitis

Answer 13

Painful breast, esp. whilst breast feeding
Fever / Malaise
Tender, red, swollen, + hard area of the breast, usually in a wedge-shaped distribution.
Reduced milk secretion

Question 14

What can non-lactational mastitis mimic?

Answer 14

Inflammatory breast cancer

Question 15

Give 4 features suggestive of infective mastitis

Answer 15

Nipple fissure that looks infected.
Purulent discharge.
Influenza-like Sx + pyrexia lasting for longer than 24h.
Considerable breast discomfort.

Question 16

Give 2 features suggestive of infective mastitis in lactating women

Answer 16

Sx not improving (/ worsening) after 12–24h despite effective milk removal.
+ve breast milk culture

Question 17

Give 4 features of when breast abscess should be suspected?

Answer 17

Hx of recent mastitis/ prior breast abscess.
Fever +/or malaise- may have subsided if taken abx for suspected infectious mastitis.
Painful, swollen lump in the breast, with redness, heat, + swelling of overlying skin.
OE: lump may be fluctuant with skin discolouration.

Question 18

Describe diagnosis of mastitis

Answer 18

Clinical dx
+/- milk culture
+/- imaging

Question 19

When is breast milk culture indicated?

Answer 19

Inadequate response to initial empirical abx
Severe burning breast pain, indicative of ductal infection

Question 20

Give 3 indications for imaging in mastitis

Answer 20

Poor response to empiric abx (within 48-72h)
Exclude ddx
Evaluation for complications e.g. abscess

Question 21

Describe initial management for puerperal mastitis

Answer 21

Reassure
Continue breastfeeding
Analgesia
Warm compresses

Question 22

When are antibiotics indicated in puerperal mastitis?

Answer 22

If has nipple fissure that is infected
Sx have not improved (/ worsening) after 12–24h despite effective milk removal
+/or breast milk culture is +ve.

Question 23

Which antibiotics are used in lactational mastitis if milk cultures are unavailable?

Answer 23

Flucloxacillin 500mg QDS for 10–14 days.

If pen allergic: Erythromycin 250–500mg QDS or Clarithromycin 500mg BD for 10–14 days.

Question 24

How should you advise women on commencement of antibiotics for lactational and non-lactational mastitis?

Answer 24

Advise to seek immediate medical advice if Sx fail to settle after 48h of Abx Tx

Question 25

Describe management of non-lactational mastitis

Answer 25

Reassure
Analgesia: paracetamol/ ibuprofen
Warm compress
Abx for all

Question 26

Which antibiotics are used in non-lactational mastitis?

Answer 26

Co-amoxiclav 500/125mg TDS for 10–14 days.
If pen allergic: Erythromycin (250–500mg QDS) or Clarithromycin (500mg BD) + Metronidazole (400mg TDS) for 10–14 days.

Question 27

What alternate cause may periductal mastitis and abscess formation in older woman be due to? How does this influence management?

Answer 27

Anaerobes
Add Metronidazole

Question 28

List 3 complications of mastitis

Answer 28

Sepsis
Recurrent mastitis
Abscess

Question 29

Describe management of breast abscess in primary care

Answer 29

Urgent referral to secondary care (surgeons) for confirmation of dx + mx

Question 30

What investigations may be performed for breast abscesses?

Answer 30

USS: confirms dx
US guided needle aspiration: drainage + culture

Question 31

Describe management of breast abscess

Answer 31

1st: US-guided aspiration with abx + reassess in 48h
(admit for IV abx if acutely unwell)

2nd: I+D + culture of fluid; usually ONLY if overlying skin necrosis/ failure of percutaneous drainage

Question 32

How is nipple candiasis treated?

Answer 32

If nipple candidiasis => antifungal therapy (nystatin or miconazole or ketoconazole for mum + nystatin for infant)

Question 33

In which 3 circumstances should women with mastitis be admitted?

Answer 33

Signs of sepsis (tachycardia, fever + chills).
Infection progresses rapidly.
Haemodynamically unstable or immunocompromised.