A 29-year-old woman presents with a fever. She had a Caesarean section 3 weeks ago and was recovering well until 2 days ago when she became very cold and shivery at night. She has been unable to keep herself warm despite several blankets and has reduced appetite, nausea, vomiting and lethargy. She is breast-feeding and has had very sore nipples since the birth but feels this is normal and has been using camomile ointment to soothe them. In the last 24 h she has noticed the left breast has become sore and red.
She has mild lower abdominal pain at the site of the Caesarean section wound. She no longer has vaginal bleeding but has a moderate brown discharge with an odour which she says is improving. Bowel habit is normal and she has no urinary symptoms.
On examination the woman is wearing a jersey and jacket, with a blanket over her. Her temperature is 38.6°C. Blood pressure is 120/64 mmHg and heart rate 106/min. The chest is clear and heart sounds are normal. The right breast is normal but there is a well- demarcated area of redness over the superiolateral aspect of the left breast, which is ten- der and hot to touch.
The uterus is firm and is non-tender, just palpable above the symphysis pubis. There is no leg swelling.
· How would you interpret the investigations?
· What is the likely diagnosis and differential diagnosis?
· How would you investigate and manage this woman?
The blood and protein on urinalysis are likely to be due to contamination from persisting vaginal discharge (lochia), but there is no evidence of urinary tract infection (no leuco- cytes or nitrites).
The haemoglobin is slightly low, which can occur with sepsis but is also common after pregnancy and delivery. The leucocytosis with neutrophilia and raised C-reactive protein suggests a significant bacterial septic process. Urea is raised while creatinine and potas- sium are normal, suggesting dehydration secondary to sepsis, pyrexia and vomiting.
The diagnosis is mastitis (a localized infection within the breast tissue). This occurs in 5 per cent of lactating women. The pathophysiology probably involves colonization of the breast ducts by bacteria through the cracked nipples, causing localized inflammation and obstruction of the duct with subsequent retention of milk, and infection. The commonest organism is staphylococcus from the skin. The differential diagnosis is of a breast abscess which would be palpated as a fluctuant mass in the breast.
Blood cultures and a swab from the breast milk or nipple are necessary. In cases of diag- nostic doubt, an ultrasound scan can differentiate mastitis from an abscess.
The woman should be admitted for intravenous antibiotics and fluids, regular paraceta- mol, analgesia and anti-emetics as necessary. Until cultures are available, flucloxacillin should be commenced with consultation with a microbiologist if some improvement is not seen within 24 h.
She should be encouraged to continue breast-feeding. If this is too painful she should express milk in order to try to unblock the duct. If an abscess is diagnosed then needle aspir- ation under local anaesthetic is preferred to formal incision and drainage in most cases.