A 30-year-old woman presents 1 week after an elective caesarean section with 24-hour history of an exquisitely painful, swollen right breast. She reports mixed feeding her newborn. She has no significant past medical history and takes no regular medications. She is found to be hypotensive and tachycardic, with a BP of 95/60 and a HR of 130.
Initial lab results reveal a WCC of 16.7, a CRP 190, a sodium of 143, urea of 10.3, a creatinine of 151, lactate of 4.1 and a blood glucose of 12.1. Her breast is tense and slightly red, though very tender to palpation. A provisional diagnosis of mastitis complicated by septic shock is made, and she is commenced on appropriate broad-spectrum antibiotics and IV fluid resuscitation.
After 2 hours in the department blistering is noted to the skin of her right breast and a repeat lactate shows a rise to 5.9. At this stage a diagnosis of necrotising fasciitis is considered, and urgent surgical referral for debridement made.