Mastitis
Key Points
- Mastitis is inflammation and/or infection of the breast that occurs most often during breast-feeding
- Classic signs: Fever, chills, flu-like symptoms, and a painful, hot, reddened area of the breast
- Most common cause: Clogged ducts, engorgement, or nipple trauma from incorrect latch that creates breaks in skin integrity allowing bacterial entry
- Constrictive bras or clothing can compress ducts, increase milk stasis, and raise mastitis risk.
- Nonlactational mastitis and periductal mastitis can mimic breast cancer and require careful imaging, culture, and biopsy triage as indicated.
- Management: Continue breast-feeding (or pump to empty), NSAIDs/acetaminophen, cool/warm compress, antibiotics are routinely ordered to prevent progression to breast abscess
- Nurse assesses latch quality and teaches nipple care as primary prevention
Pathophysiology
Mastitis results from milk stasis + bacterial entry:
- Milk stasis: Incomplete breast emptying from poor latch, missed feedings, constricting clothing, or engorgement → milk accumulates → painful, firm, clogged duct area
- Bacterial entry: Nipple fissures or cracks (from incorrect latch) allow bacteria (most commonly Staphylococcus aureus) to enter breast tissue
- Inflammatory response: Infection develops → fever, localized heat, redness, swelling
If untreated, mastitis can progress to breast abscess — a localized collection of pus requiring surgical drainage.
Nonlactational Mastitis and Periductal Mastitis
Nonlactational mastitis (NLM) occurs in patients who are not breast-feeding and may be inflammatory or infectious; common pathogens include Staphylococcus species.
Periductal mastitis (PDM)/mammary duct ectasia involves chronic duct inflammation with duct dilation, wall thickening, and leakage into surrounding tissue, which can lead to fat necrosis and abscess formation.
Because NLM/PDM can clinically resemble malignancy, diagnostic workup may include ultrasound, diagnostic mammography, MRI, nipple-drainage culture/pathology, and FNA or tissue biopsy.
Risk Factors
- Incorrect nursing latch → nipple cracking or bleeding
- Breast engorgement or hyperlactation
- Missed or infrequent feedings
- Constrictive clothing that compresses milk ducts
- Nipple trauma (cracked, bleeding)
- Decreased maternal immune function (fatigue, poor nutrition)
- Poor hand hygiene before nursing
- NLM/PDM risk context: obesity, smoking, and diabetes mellitus
Clinical Presentation
| Sign/Symptom | Description |
|---|---|
| Fever | Temperature ≥100.4°F (38°C) |
| Chills, malaise, flu-like symptoms | Systemic inflammatory response |
| Localized breast pain | Tender, hot, hard, wedge-shaped area |
| Breast redness | Unilateral erythema over affected lobe |
| Engorgement | Breast feels firm and overfull |
Nursing Assessment
Breast assessment: Inspect for redness, warmth, hardness, localized tender area.
LATCH Assessment (evaluate latch quality to identify root cause and prevent recurrence):
| LATCH Element | 0 | 1 | 2 |
|---|---|---|---|
| Latch | Sleepy, no latch | Holds nipple only | Holds nipple and areola, lips flanged |
| Audible swallowing | None | Rarely | Frequently |
| Type of nipple | Inverted | Flat | Everted |
| Comfort | Severe pain | Moderate pain | No pain |
| Hold | Requires full assist | Minimal assist | Independent |
Higher LATCH score = better latch. Poor latch is the primary preventable cause of mastitis.
Nursing Interventions
Non-pharmacologic:
- Encourage breast-feeding every 2–3 hours (or pumping if too painful) to empty breasts and relieve milk stasis
- Apply cool OR warm compress to reddened area for comfort
- Inspect nipples for cracking or redness after each feeding
- Teach correct latch technique — if it hurts, remove baby and relatch
- Increase fluid intake to maintain milk supply
- Encourage rest and adequate nutrition
Pharmacologic:
- NSAIDs (ibuprofen) or acetaminophen for pain and inflammation
- Antibiotics (e.g., dicloxacillin, cephalexin) — routinely ordered for confirmed mastitis; must start promptly to prevent abscess
- Most antibiotics safe with breast-feeding — continue nursing through treatment
- In NLM/PDM, tailor antibiotics to culture/sensitivity and evaluate for incision and drainage when abscess is present
- Consider hospitalization when infection progresses despite oral therapy, sepsis signs are present, or the patient is clinically unstable
Antibiotic Urgency
Prompt antibiotic treatment is essential. Untreated or delayed treatment of mastitis can progress to breast abscess, which requires incision and drainage. The nursing person should be instructed to contact their provider immediately if symptoms worsen despite antibiotics.
Thrush (vs. Mastitis)
Thrush (Candida nipple infection) can mimic mastitis:
- Signs: Red rash around nipple, itching, burning, shooting pain with latch
- Both the nursing person and newborn’s mouth must be treated with antifungal medication simultaneously
- Prevention: Keep nipples dry between feedings; change nursing pads when damp
Patient Education at Discharge
- Complete the full course of antibiotics even if symptoms improve
- Continue breast-feeding or pumping — stopping increases engorgement and milk stasis
- Apply nipple ointment after feedings to prevent cracking
- Perform thorough handwashing before nursing
- Contact provider if: fever increases, pain worsens, breast becomes fluctuant (may indicate abscess), or symptoms do not improve within 48–72 hours of antibiotics
Related Concepts
- postpartum-infections — Mastitis within the context of all postpartum infections (endometritis, UTI, wound)
- postpartum-hemorrhage — Concurrent complication monitoring in the postpartum period
- care-of-common-problems-in-the-newborn — Infant feeding difficulties associated with mastitis risk
- birth-related-complications — Postpartum complications overview
- antibiotics — Antibiotic classes used for mastitis treatment
Self-Check
- A postpartum day 5 patient calls the clinic complaining of fever (101.2°F), chills, and a hot, red, painful area on her right breast. She is breast-feeding every 3 hours. What is the priority nursing assessment, and what treatment does the nurse anticipate will be ordered?
- A breast-feeding patient with mastitis asks the nurse if she should stop nursing because of the infection. What is the correct nursing response?
- What distinguishes thrush from mastitis, and why must both the nursing person and the infant be treated simultaneously for thrush?