Fever of 38.5°C or more, flu-like aches, chills and a tender, erythematous and edematous area of the breast is observed in puerperal mastitis [1]. Women often report of malaise and fatigue as well [5].

The diagnosis should be made rather easily based on clinical findings [5]. It is important to identify the causative agent, however and cultivation of aspirated samples should be performed, the primary reason being determination of optimal antimicrobial therapy due to the growing issue of antimicrobial resistance, particularly in the setting of MRSA [3].

Antimicrobial therapy is the mainstay of puerperal mastitis treatment. For non-MRSA organisms, dicloxacillin (500 mg PO q6h) or cephalexin (500 mg PO q6h) are given in the outpatient setting, whereas nafcillin or oxacillin 2 g IV q4-6h is recommended once patients are admitted [4]. When MRSA is suspected, trimethoprim-sulfamethoxazle (TMP-SMX) is given as a double-strength tablet every 12 hours [4]. Alternative regimens include clindamycin 300 mg PO q6h for outpatients, while intravenous vancomycin 1 gm q12h is recommended in hospital conditions [4]. If an abscess in the breast has developed, surgical drainage or needle aspiration, in addition to antibiotic therapy, is necessary [5]. In addition to antibiotics and surgery, non-steroidal anti-inflammatory drugs (NSAIDs) should be given to reduce the symptoms provoked by inflammation [3].

The prognosis is good with early therapy, but complications may occur, most notable being breast abscess [2], while rare cases have described sepsis as a complication, suggesting the importance of an early diagnosis.

The most important causative agents of puerperal mastitis are Staphylococcus aureus and coagulase-negative staphylococci (CoNS) [1], whereas Streptococcus pyogenes, Escherichia coli, Bacteroides sp., Pseudomonas aeruginosa, Proteus mirabilis and Corynebacterum sp. (rare) are other notable pathogens [4] [7]. Unfortunately, an increased frequency of Methicillin-resistant S. aureus (MRSA) infection has been observed [6].

Overall prevalence of puerperal mastitis ranges between 10% in the United States, 15-20% in Australia and up to 24% in Finnish women [1] [2]. Risk factors associated with mastitis are nipple damage, maternal fatigue, milk stasis, history of mastitis, use of an antifungal nipple cream and an increased frequency of breastfeeding [2]. Some studies have determined that African American women are at a higher risk for the development of a breast abscess, as are obese women and cigarette smokers [7].

Bacterial colonization of the breast and its connective tissue is the principal event in the pathogenesis of puerperal mastitis. Presumably, milk stasis, nipple damage and other factors promote invasion of microbial organisms into the breast, leading to acute inflammation and the appearance of symptoms.

Complete emptying of the breast, optimization of breastfeeding techniques and a reduction in breastfeeding frequency (< 10 times per week) are strategies that can reduce the risk for mastitis [2] [5], but so far, neither of the mentioned strategies have been confirmed in large-scale studies [3].

Puerperal (or lactation) mastitis is a term that describes inflammation of the interlobular connective tissue within the mammary gland during puerperium - the first 6 weeks postpartum [1]. Most common causes are Staphylococcus aureus, coagulase-negative staphylococci (CoNS) and other bacterial pathogens, but microbial invasion may not be the cause in all cases [2]. Approximately 10-25% of women develop puerperal mastitis in different parts of the world and risk factors include nipple damage, milk stasis, previous history of mastitis and an increased breastfeeding frequency [2]. Clinical signs are fever, chills, fatigue, and the presence of a tender, edematous, erythematous area of the breast that is inflamed and painful [1]. The diagnosis is made on clinical grounds and cultivation of aspirated breast fluid should be performed to identify the causative agent [3]. Antibiotics are the mainstay of therapy, but it is imperative to conduct antimicrobial susceptibility testing, to initiate optimal treatment and to avoid the risk of resistance [4]. Mastitis does not pose a risk for the infant and breastfeeding should not be ceased during the infection [5], but it is important to recognize the condition early on and treat it appropriately, as breast abscesses (but also sepsis) can occur.

Puerperal mastitis is a term that describes inflammation of breast tissue in the first 6 weeks after delivery (known as the puerperium). In most cases, bacterial organisms such as Staphylococcus aureus cause an infection that leads to inflammation. Approximately 10% of women in the United States develop puerperal mastitis, while somewhat higher rates (15-25%) have been observed in Australia and Finland. Various risk factors have been described - nipple damage, milk stasis, previous history of mastitis and increased breastfeeding frequency, all promoting colonization of breast tissue with bacteria. Symptoms include high fever, fatigue and a painful, red, swollen and tender area of the breast that makes the condition easy to recognize. Nevertheless, it is necessary to identify the organism responsible for the infection, in order to determine optimal antibiotic therapy, the mainstay of treatment. In rare cases, breast abscesses and even sepsis can ensue, which is why early recognition of the infection is vital. Preventive strategies such as complete emptying of the breast, reduced breastfeeding frequency and correction of breastfeeding techniques have been proposed, but their true effects are yet to be confirmed.

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