Diagnosis

Mastitis

Etiology

Cause [dgu]

• Puerperal mastitis: mastitis in lactating women (Staphylococcus aureus)

• Nonpuerperal mastitis: polymicrobial (Pseudomonas, Staphylococcus aureus, and Corynebacterium)

  • Trauma

  • Fibrocystic disease

  • Breast cancer

  • Unrecognized etiology

  • Idiopathic granulomatous mastitis (rare inflammatory disease of unknown etiology)

Pathophysiology [n8i]

1. Cracked or painful nipples:

   --> the mother avoids complete emptying on the painful side

   --> bacteria gain access

2. Poor drainage: Insufficient emptying or obstruction of ducts by tight clothing

3. Plugged ducts --> Milk accumulation/engorgement

4. Non-infective inflammation

5. Infective inflammation: if presence of an organism

   • Staphylococcus aureus (50%), Escherichia coli, Streptococcus species, Bacteroides species.

   • Less common: Candida albicans and Mycobacterium tuberculosis

6. Abscess formation

Risk of chronic mastitis

• Microabscess formation

• Granulomas

• Nipple retraction

• Sinus formation

• Axillary lymphadenopathy

• Galactorrhea

• Pain

• Peau d’orange

• Discharge

• Tumor

Complication [sts]

• Breast abscess

• Fistula formation

• Scarring and deformity of the breast tissue

Epidemiology

Incidence per 100.000 [yrs][ywg][n8i]

Approach

• Blood test:

• Milk analysis: bacteria count, leukocyte count, culture, CRP

• Ultrasonography of the breast

• Mammography

• MRI

Treatment

1. Early non-infective mastitis: reduce milk stasis [n8i][sts]

   • Local massage

   • Empty the affected side by feeding or pumping

   • Bed rest

   • Hydration

   • Reduce pain: ice packs or warm packs

   • Analgesics: acetaminophen or NSAIDs

   • Loose clothing

2. Infective mastitis: Antibiotics

   • 1st gen cephalosporins or dicloxacillin/oxacillin

   • Gram-negative organisms: 1st gen cephalosporins or amoxicillin clavulanate

3. Abscess formation:

   • Incision and drainage

   • Anaerobic coverage with Augmentin or clindamycin

Differential diagnoses

Breast abscess, Breast cancer, Cat scratch disease, Cryptococcosis, Cystosarcoma phyllodes, Fat necrosis, Fibroadenoma, Fibrocyst, Gynecomastia, Hidradenitis suppurativa, Histoplasmosis, Leprosy, Mammary duct ectasia, Mondors disease, Sarcoidosis, Tuberculosis, Wegener's granulomatosis