What are the expected physical exam findings in a woman with mastitis?

Physical Exam Findings in Mastitis

On physical examination of a woman with mastitis, you should expect focal breast tenderness, erythema or hyperpigmentation of the overlying skin occupying at least one-third of the breast, warmth, and possible swelling, with or without an underlying palpable mass. 1, 2

Key Clinical Findings

Primary Examination Features

• Focal breast tenderness with pain localized to the affected area 2
• Erythema or hyperpigmentation of the overlying skin, typically covering at least one-third of the breast 1, 2
• Warmth over the affected breast tissue 2
• Swelling or edema of the breast 2
• Palpable mass or area of induration may or may not be present 1, 3

Additional Findings to Assess

• Nipple changes including retraction, crusting, or flattening may be present 1, 3
• Nipple discharge in some cases 3
• Skin changes such as peau d'orange (orange peel appearance), ulceration, or subcutaneous tissue thickening 3
• Axillary lymphadenopathy with palpable enlarged lymph nodes 3

Systemic Signs

• Fever is common and indicates systemic involvement 2, 4
• Malaise or general feeling of unwellness 2
• In rare cases, extramammary manifestations such as erythema nodosum or polyarthralgia may occur with granulomatous mastitis 4

Critical Pitfall: Excluding Inflammatory Breast Cancer

A crucial caveat is that inflammatory breast cancer (IBC) can mimic mastitis clinically, particularly in non-puerperal women or when symptoms fail to respond to antibiotics. 5, 6

Red Flags for Malignancy

• History of mastitis not responding to at least 1 week of antibiotics should raise suspicion for IBC 5, 1
• Rapid onset of symptoms (duration less than 6 months) with erythema, edema, or peau d'orange 5
• Persistent or growing palpability after treatment of inflammatory changes 6
• Non-puerperal presentation in middle-aged or older women warrants heightened suspicion 6, 7

When to Pursue Further Evaluation

• If clinical findings persist despite appropriate antibiotic therapy, imaging (ultrasound and/or mammography) should be performed to exclude underlying malignancy 1, 2, 6
• Follow-up imaging is essential after resolution of inflammatory changes to detect any previously masked masses 6
• In cases with persistent symptoms or high clinical suspicion, core needle biopsy or skin punch biopsy should be obtained to confirm or exclude malignancy 5

Examination Technique Considerations

• Assess for asymmetry compared to the contralateral breast 5
• Evaluate whether any mass is three-dimensional and distinct from surrounding tissue 5
• Check for skin dimpling or attachment to deep fascia 5
• Document the extent of erythema (what proportion of the breast is involved) 5, 1