1 INTRODUCTION
Acute mastitis is a common problem during breastfeeding, and it is estimated that approximately one in five breastfeeding women has experienced acute mastitis.1-3 Mastitis episodes are often characterized by rapid progression with local redness and breast pain and are accompanied by systemic symptoms, including fever, headache, nausea, vomiting, etc. Unlike mastitis sufferers abroad who get medical help from community, mastitis sufferers in mainland China often receive medical help from physicians in the hospital, and most of them have to go to the emergency department (ED) because of high fever, intolerable pain and fear of breastfeeding cessation.
The underlying causes of acute mastitis include stress, over nutrition, overreliance on breast pumps, and a lack of breastfeeding experience. Two direct causes of acute mastitis, milk stasis and bacterial infection, are important and determine the treatment strategies.4,5 Conservative treatments, the purpose of which is to relieve milk stasis and that include hot or cold compresses, acupuncture and the application of cabbage leaves, have been demonstrated to be inconclusive for managing milk stasis.6 Numeroud literature showed that therapeutic breast massage was helpful for emptying the breast and relieving milk stasis.7-9 Antibiotic targeting pathogenic organism is theoretically useful for eliminating inflammation and decreasing abscess formation. However, in some situations, acute mastitis is just an inflammatory condition, and there is no pathogenic bacterial infection. Therefore, conservative treatments seem adequate, and the additional use of antibiotics may be unnecessary in such situations.
In practice, although the role of conservative treatments for relieving milk stasis is inconclusive, the following treatments are still important for acute mastitis: breast massage for emptying the breast, ibuprofen for analgesia, a hot compress applied prior to breastfeeding for stimulating milk flow, and a cool compress applied after breastfeeding for reducing swelling and pain. In addition, oral or intravenous flucloxacillin is preferred for mastitis episodes that need antibiotics, and clindamycin is chosen for the patient who is allergic to penicillin. If the signs and symptoms improve within 24-48 hours in patients who are prescribed antibiotics, a total duration of five to seven days is encouraged; if the signs and symptoms are not improved or are even worse, antibiotics with different mechanisms are started immediately, and human milk is collected for cultivation and sensitivity tests.4
Two inflammatory markers, serum leukocyte counts (SLCs) and C-reactive protein (CRP), are widely used in acute inflammatory diseases, such as acute appendicitis and cholecystitis. However, the associations between these two inflammatory markers and infectious diseases are complex, and few studies focusing on these two inflammatory markers and acute mastitis have been reported. Osterman K et al. conducted a prospective study to compare serum SLCs and CRP among 41 episodes of lactation mastitis.10 Bacterial cultivation of breast milk was performed in all patients, and patients were classified into two groups based on the presence of potentially pathogenic bacteria: group A without potentially pathogenic bacteria and group B with potentially pathogenic bacteria. They found that the mean SLCs were significantly higher in group B than in group A; however, although the levels of CRP in both groups were elevated, there was no significant difference between the two groups.10
A positive relationship between higher SLCs and the presence of potentially pathogenic bacteria indicates that mastitis with higher SLCs is more likely to be infectious disease and should be treated with the addition of antibiotics as well as conservative treatments. However, no relative study has been performed since then. Therefore, the purpose of our study was to describe the clinical characteristics, treatment regimens and treatment outcomes of acute mastitis in breastfeeding women and to further explore the value of SLCs for initial antibiotic use in breastfeeding women with acute mastitis in mainland China.