A 32-year-old mother from urban Delhi is exclusively breastfeeding her 6-week-old female infant. She presents with a 3-day history of a painful, red, swollen area in the upper outer quadrant of her left breast. Temperature is 39.2°C. On examination, there is a localized area of erythema, induration, and warmth; fluctuance is not appreciated. The infant is feeding well from both breasts without difficulty. The mother has no history of cracked nipples or poor latch. What is the most appropriate next step in management?

Explanation

## Lactational Mastitis: Diagnosis and Evidence-Based Management ### Clinical Diagnosis **Key Point:** Lactational mastitis is characterized by localized breast inflammation (erythema, induration, warmth) + systemic symptoms (fever ≥38.5°C, malaise) occurring in the first 6 weeks postpartum. The absence of fluctuance indicates cellulitis without abscess formation. ### Diagnostic Criteria for Mastitis | Criterion | Present in This Case | |-----------|----------------------| | **Localized erythema** | Yes (upper outer quadrant) | | **Induration/swelling** | Yes | | **Fever (≥38.5°C)** | Yes (39.2°C) | | **Systemic symptoms** | Implied (fever, pain) | | **Fluctuance** | No (cellulitis, not abscess) | | **Onset** | Day 21 postpartum (within risk window) | ### Management Algorithm ```mermaid flowchart TD A[Suspected lactational mastitis]:::outcome --> B{Fluctuance present?}:::decision B -->|Yes| C[Ultrasound to confirm abscess]:::action C --> D[Needle aspiration or I&D + antibiotics]:::action B -->|No| E[Cellulitis: empirical antibiotics]:::action E --> F[Continue breastfeeding from both breasts]:::action F --> G[Reassess at 48-72 hours]:::decision G -->|Improving| H[Continue antibiotics for 10-14 days]:::action G -->|Worsening/no improvement| I[Ultrasound to rule out abscess]:::action I --> J{Abscess?}:::decision J -->|Yes| D J -->|No| K[Change antibiotic, consider resistant organism]:::action ``` ### Antibiotic Selection **High-Yield:** First-line agents for lactational mastitis: - **Amoxicillin-clavulanate** 500/125 mg TDS for 10–14 days (covers *Staphylococcus aureus*, including MRSA in endemic areas) - **Cephalexin** 500 mg QID for 10–14 days (alternative if penicillin allergy) - **Cloxacillin** 500 mg QID (if MRSA coverage needed) **Clinical Pearl:** Most cases of mastitis are caused by *Staphylococcus aureus* (including MRSA in some regions) or *Streptococcus agalactiae*. Empirical antibiotics should cover these organisms. ### Supportive Measures 1. **Continue breastfeeding** from both breasts—milk removal is essential for resolution 2. **Frequent feeding** (8–12 times per 24 hours) 3. **Warm compresses** before feeding to promote milk flow 4. **Analgesics** (paracetamol, ibuprofen) for pain and fever 5. **Reassess at 48–72 hours**; if no improvement, obtain ultrasound to rule out abscess **Warning:** Do NOT stop breastfeeding or express milk only—continued milk removal is critical for resolution and prevents abscess formation. ### Why This Answer Is Correct The clinical presentation (localized erythema, induration, fever, no fluctuance) is consistent with cellulitis-stage mastitis. Empirical antibiotics + continued breastfeeding + reassessment at 48 hours is the evidence-based approach. Ultrasound is reserved for cases that fail to improve or show signs of abscess formation.