Breast abscess

A breast abscess is a pocket of pus inside the breast, walled off from the surrounding tissue. It appears most often in women who are breastfeeding, as the sequel to mastitis that was not brought under control in time. Its defining feature is this: once pus has collected into a cavity, antibiotics alone can no longer deal with it, because the drug barely penetrates inside. The pus has to be let out, and the sooner that happens, the smaller the procedure.

Where the pus in a breast comes from

In someone who is breastfeeding the chain of events is usually the same. Milk stagnates in one part of the gland, the tissue around it swells and becomes inflamed, and bacteria from the skin or from the baby's mouth get in through cracks in the nipple. At first this is mastitis: a hard, painful area, redness and a temperature. If the milk is not got moving and treatment is not started, a cavity forms in the middle of that area within a few days.

Milk stagnates most often because of a poor latch, feeds that are infrequent or skipped, abrupt weaning, pressure from a tight bra, from a bag strap or from a finger resting on the breast during a feed, or from sleeping face down.

Abscesses also occur in people who are not breastfeeding, and even in men; they then sit close to the areola and are linked to inflammation of the ducts. Here smoking is the leading cause: it damages the lining of the ducts, and in smokers these abscesses come back stubbornly in the same place. Other contributors are nipple piercing, diabetes, a weakened immune system and injury to the breast.

What it feels like

• a painful lump that feels tense, as though filled with fluid;
• the skin over it is hot, stretched and shiny; redness shows up well on pale skin and much less on brown and black skin, so pain and swelling are the more reliable guide;
• fever, shivering, aching limbs and a sense of being completely wiped out;
• enlarged, tender glands can be felt in the armpit on the same side;
• pus starts to leak from the nipple or from a point on the skin, meaning the cavity has found its own way out.

The most useful practical rule is this: mastitis that is being treated properly starts improving within two days. If the pain and fever persist forty-eight hours after antibiotics were started, or the lump has become sharply defined, an abscess is the likely answer and an ultrasound scan is needed.

When help is needed the same day

• a temperature above 38.5 °C with violent shivering;
• redness spreading rapidly across the breast, with purple or greyish patches of skin or blisters;
• sudden weakness, dizziness, confusion, rapid breathing, cold clammy skin — this is how blood poisoning shows itself;
• an abscess in a newborn or in a pregnant woman;
• pus has drained but the general condition keeps getting worse.

In these situations there is no point waiting for the morning or for a booked appointment.

A similar picture with something else behind it

There is a rare but genuinely important trap. Inflammatory breast cancer looks almost exactly like an infection: the breast turns red, swells, feels hot, and the skin takes on the texture of orange peel. The difference is that there is no pus, and the picture does not answer to antibiotics — or answers only partly and then returns at once.

Hence the rule breast specialists follow: if the area does not behave the way infection should behave — it fails to settle after two or three weeks of correct treatment, it recurs in the same spot, or it appeared for no clear reason in a woman who is not breastfeeding — mammography or ultrasound and a biopsy are needed. This is exactly why, when draining an abscess, the doctor often takes a small piece of the cavity wall for examination.

None of this is a reason to fear the worst at the first lump: in someone breastfeeding, the overwhelming majority of these areas are ordinary mastitis. But an "abscess" that drags on and refuses to respond has to be investigated to the end.

How the pus is let out and what else is used

An ultrasound scan comes first: it shows whether there is a cavity, exactly where it lies and how much of it there is. The method is chosen after that.

• Needle aspiration under ultrasound guidance. The usual approach for most abscesses. The skin is numbed and the pus is drawn out with a syringe. One session is not always enough: the cavity may refill, and the procedure is repeated a few days later.
• A small incision with drainage. Needed when the cavity is large, divided by partitions, when the pus is too thick, or when the skin over it has thinned to the point of breaking down.

The pus is sent for culture, which shows which bacterium is responsible and which drugs work against it. Antibiotics are given alongside drainage, not instead of it; they are chosen from the groups active against staphylococcus, and if there is penicillin allergy a substitute from another class is found. The course has to be finished even when the pain went away on day two.

Between visits simple things help: an over-the-counter painkiller, a cold pack on the breast after the procedure, and a bra that supports without compressing. Healing takes anything from a few days to a few weeks and leaves a small scar where the incision was.

Breastfeeding during treatment

Feeding can and should usually continue, including from the affected breast. That milk is safe for a healthy, full-term baby, and emptying the gland regularly speeds recovery, because stagnation keeps the inflammation going.

If latching hurts, or the incision has ended up next to the areola, express by hand or with a pump as often as you would have fed. The milk can still be given to the baby unless your doctor says otherwise. There is no need to stop breastfeeding because of an abscess: stopping abruptly causes fresh stagnation and can make things worse. Do say that you are breastfeeding, since it is taken into account when the antibiotic and the painkiller are chosen.

What lowers the chance of it happening again

• get the latch sorted out with a breastfeeding counsellor: most episodes of stagnation begin there;
• do not skip feeds or leave long gaps overnight in the early months;
• wean gradually rather than in a single day;
• treat cracked nipples and do not accept pain while feeding as normal;
• wear a bra that fits, without underwiring that presses on one spot;
• start treating mastitis straight away instead of hoping it will pass;
• stop smoking if the abscess arose outside breastfeeding and has already recurred;
• keep blood sugar under control if you have diabetes.

Online consultation

In an online consultation the doctor will go through how it started and how it has changed over recent days, judge whether this still looks like mastitis or already like an abscess, explain whether an ultrasound scan is urgent and what can be done about feeding right now. If the situation calls for hands-on treatment, you will be told so plainly and pointed to the right person.

This material is for information only and does not replace medical advice.