Postdelivery Emergencies

Trends in clinical management of lactational mastitis among women attending Australian general practice: a national longitudinal study using MedicineInsight, 2011-2022

OBJECTIVE

To examine longitudinal trends in clinical management of lactational mastitis in women attending general practice.

DESIGN

Open cohort study.

SETTING

Australian general practice using data from MedicineInsight.

PARTICIPANTS

Women aged 18 to 44 years with one or more clinical encounters for lactational mastitis between January 2011 and July 2022.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome measure was the proportion of prescribed oral antibiotics based on the antibiotic type. Secondary outcome measures were the proportion of women prescribed other medications (eg, antifungals, lactation suppressants) or ordered selected clinical investigations including breast ultrasound, blood test, breast milk culture, nipple swab culture or breast aspirate. Outcomes were examined based on the calendar year and individual- or clinical practice-level characteristics.

RESULTS

Among 25 002 women who had one or more clinical encounters related to mastitis, 90.9% were prescribed oral antibiotics. While the proportion of women prescribed an oral antibiotic remained consistent from 2011 to 2022 (91.1% vs 92.5%), there were changes in the proportion receiving prescriptions for di/flucloxacillin (46.1% vs 60.4%) and cefalexin (38.6% vs 26.5%). Fewer than 12% of women were clinically investigated for their mastitis encounter, most commonly a breast ultrasound (7.1%), followed by a selected blood test (3.8%). Requests for breast milk cultures, nipple swab cultures or breast aspirates occurred in less than 1.1% of individuals. Significant increases were evident with respect to ordering of all clinical investigations, with rates at least doubling between 2011 and 2022 (6.6% vs 14.7%). Large variability in clinical management was evident according to both individual- (eg, concessional status) and clinical practice-level characteristics (eg, remoteness).

CONCLUSIONS

Australian general practitioners commonly prescribe oral antibiotics to women with mastitis and largely in line with clinical guidelines. Their use of clinical investigations as part of mastitis management has increased over the last decade.

General practitioners' management of mastitis in breastfeeding women: a mixed method study in Australia

BACKGROUND

Mastitis is a common reason new mothers visit their general practitioner (GP). In Australia, the Therapeutic Guidelines: Antibiotic provides practical advice to GPs managing a range of infections, including mastitis. It is not known if Australian GPs prescribe antibiotics and order investigations as recommended for the management of mastitis.

METHODS

A convergent mixed methods design integrated quantitative analysis of a general practice dataset with analysis of interviews with GPs. Using the large-scale primary care dataset, MedicineInsight, (2021-2022), antibiotics prescribed and investigations ordered for mastitis encounters were extracted. Mastitis encounters were identified by searching 'Encounter reason', 'Test reason' and 'Prescription reason' free text field for the term 'mastitis'; 'granulomatous mastitis' was excluded. Clinical encounters for mastitis occurring within 14 days of a previous mastitis encounter were defined as belonging to the same treatment episode. Semi-structured interviews were conducted with 14 Australian GPs using Zoom or telephone in 2021-2022, and analysed thematically. The Pillar Integration Process was used to develop a joint display table; qualitative codes and themes were matched with the quantitative items to illustrate similarities/contrasts in findings.

RESULTS

During an encounter for mastitis, 3122 (91.7%) women received a prescription for an oral antibiotic; most commonly di/flucloxacillin ([59.4%]) or cefalexin (937 [27.5%]). Investigations recorded ultrasound in 303 (8.9%), blood tests (full blood examination [FBE]: 170 [5.0%]; C-reactive protein [CRP]: 71 [2.1%]; erythrocyte sedimentation rate [ESR]: 34 [1.0%]) and breast milk or nipple swab cultures in approximately 1% of encounters. Analysis using pillar integration showed consistency between quantitative and qualitative data regarding mastitis management. The following themes were identified: - GPs support continued breastfeeding. - Antibiotics are central to GPs' management. - Antibiotics are mostly prescribed according to Therapeutic Guidelines. - Analgesia is a gap in the Therapeutic Guidelines. - Low use of breast milk culture.

CONCLUSIONS

Prescribing antibiotics for mastitis remains central to Australian GPs' management of mastitis. Interview data clarified that GPs were aware that antibiotics might not be needed in all cases of mastitis and that delayed prescribing was not uncommon. Overall, GPs followed principles of antibiotic stewardship, however there is a need to train GPs about when to consider ordering investigations.

Puerperal mastitis caused by limited community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) clones

Objective

To outline the epidemiology of puerperal mastitis caused by methicillin-resistant Staphylococcus aureus (MRSA) and evaluate the effect of an infection control bundle on its incidence.

Methods

A surge in MRSA puerperal mastitis was noted in a community hospital in September 2009. MRSA samples from mastitis cases and the environment underwent typing using multilocus sequence typing (MLST), staphylococcal cassette chromosome mec (SCCmec), gene encoding surface protein A (spa), accessory gene regulator (agr), and pulsed-field gel electrophoresis (PFGE). The phenotypic characteristics, including superantigen toxin profiles, gene encoding Panton-Valentine leucocidin (pvl), and minimal inhibitory concentration (MIC) against vancomycin, were ascertained. Subsequently, an infection control bundle emphasizing contact precautions was introduced, and mastitis incidence rates pre- and post-intervention were compared.

Results

The majority of cases occurred within 6 weeks post-delivery in first-time mothers. Of the 42 S. aureus isolates (27 from mastitis and 15 from colonized staff and environmental sources), 25 (92.6%) clinical and 3 (20%) colonized MRSA were identified as ST59-SCCmecVT-spa t437-agr group I with a vancomycin MIC of 1 mg/L, pvl-positive, and predominantly with a consistent toxin profile (seb-selk-selr). PFGE revealed 13 patterns; pulsotype B exhibited clonal relatedness between two clinical and three colonized MRSA samples. Post-intervention, the incidence of both mastitis and MRSA mastitis notably decreased from 13.01 to 1.78 and from 3.70 to 0.99 episodes per 100 deliveries, respectively.

Conclusion

Distinct community-associated MRSA (CA-MRSA) clones were detected among puerperal mastitis patients and colonized staff. The outbreak was effectively controlled following the implementation of a targeted infection control bundle.

Invasive Group A streptococcal postpartum endometritis associated with multi-organ infarctions: an uncommon case presentation and literature review

Background: Streptococcal Toxic Shock Syndrome (STSS) is a serious condition that can arise from streptococcal postpartum endometritis. It is associated with a substantial increase in mortality rate and can rarely result in multiorgan infarction. Early recognition plays a vital role in patients' outcome. Objective: To report a case of complicated STSS and review the literature for previous case reports of streptococcal postpartum endometritis to determine if STSS diagnostic criteria (published by the Centers for Disease Control and Prevention) were fulfilled. Case presentation: This is a 41-year-old woman who presented 5 days after an uncomplicated vaginal delivery with endometritis complicated by invasive group A β-hemolytic streptococcus (GAS) infection and confirmed toxic shock syndrome. The patient was initially admitted to the critical care unit due to hemodynamic compromise requiring intravenous (IV) fluids, IV antibiotic therapy with penicillin and clindamycin, and IV immunoglobulin therapy. The patient subsequently developed multi-organ infarctions, acute respiratory distress syndrome requiring noninvasive respiratory support, and severe reactive arthritis. Literature review revealed 15 case reports of GAS postpartum endometritis, five met criteria for confirmed STSS. One patient died from severe septic shock leading to cardiopulmonary arrest. Thirteen out of 15 cases of postpartum endometritis occurred after uncomplicated vaginal delivery. Conclusion: STSS is a serious and possibly fatal medical condition that requires early diagnosis and treatment to prevent poor patient outcomes and death. Careful consideration to the patient's postpartum clinical presentation with the implementation of an intradisciplinary approach should be utilized.