Hidradenitis suppurativa (HS): symptoms, treatment and self-care

The NHS says HS is a lifelong, recurring condition that is often difficult to manage, although symptoms may improve or eventually stop with treatment. It stresses that recognising and diagnosing it early helps stop it getting worse. In the early stages it may be controlled with medicine, and surgery may be needed in severe or persistent cases.

The British Association of Dermatologists says treatment is tailored to each person. In general terms, early HS is usually treated with medication, whereas longstanding and severe HS, especially with multiple areas affected, may benefit from both medication and surgery.

The British Association of Dermatologists (BAD) describes HS as a chronic, recurrent and painful condition with inflammation: redness, tenderness, swelling and lumps. It can occur in any skin area but tends to affect areas with a type of sweat gland called apocrine glands, mainly the armpits, breasts, tummy fold, groin, genital area and buttocks.

Within these areas the hair follicles become blocked and inflamed, which causes a mixture of boil-like lumps, areas leaking pus, and scarring such as skin tunnels. HS is rare before puberty and most people notice the first lumps in early adulthood, according to the BAD. It can affect anyone, but is more common in women and in people with darker skin.

The NHS says symptoms range from mild to severe, and cause a mixture of boil-like lumps, blackheads, cysts, scarring and channels in the skin that leak pus. It tends to start with blackheads, spots filled with pus and firm pea-sized lumps in one place. The lumps either disappear or rupture and leak pus after a few hours or days, and new lumps often develop nearby.

If it is not controlled, larger lumps may develop and spread. The NHS says narrow channels called sinus tracts form under the skin and break out on the surface, leaking pus. The BAD says the abscesses are usually painful enough to make sitting or walking difficult, and that discharge may need daily dressings.

• Early stage: blackheads, pus spots, and red lumps that look like boils or cysts.

• Later stage: tunnels under the skin that leak pus, wounds that do not heal easily and increasing scarring.

• Some lumps may become infected with bacteria, which needs treating with antibiotics (NHS).

• Many people also develop a pilonidal sinus, a small hole or tunnel at the top of the buttock cleft (NHS).

For a sudden new painful abscess, the BAD suggests a warm flannel on the area or a bath, which may encourage pus to drain. Painkillers such as non-steroidal anti-inflammatories can help with pain and inflammation, a topical steroid can sometimes reduce redness and swelling, and a course of antibiotics may help. A dermatologist may also lance a boil or give a steroid injection into it for pain relief.

The NHS and BAD list day-to-day self-care. None of it replaces medical treatment, but it can make living with HS easier.

• Lose weight if you are overweight, and stop smoking if you smoke.

• Use an antiseptic skin wash or soap, which may be prescribed alongside other treatment.

• Hold a warm flannel on lumps to encourage pus to drain.

• Wear loose-fitting clothes and avoid tight underwear.

• Avoid shaving affected skin such as the armpits.

• Ask for dressings if there is drainage; the BAD says dressings should be prescribed for people with HS who have fluid drainage.

The NHS says the exact cause is unknown, but the lumps develop as a result of blocked hair follicles. The BAD says that when fluid within the follicle cannot escape, it swells and bursts, causing inflammation or abscesses. It stresses that poor hygiene does not cause HS.

Several things may play a part, according to the BAD and NHS.

• Hormones: HS usually starts around puberty and may be worse before periods, which suggests sex hormones may be involved.

• An over-active immune system causing inflammation, which is why immune-modifying treatments can help.

• Skin bacteria trapped in a blocked follicle, although the NHS notes HS is not usually associated with the bacteria that cause skin infections.

• Smoking: the BAD says up to 60% of people with HS are smokers, but non-smokers can be affected.

• Weight: it is more common in people who are overweight or obese, and the BAD says weight loss may improve symptoms.

• Family history: it runs in families in about 1 in 3 cases.

There is no definitive test. The NHS says a GP will examine the affected skin and may take a swab of an infected area, which can help because HS is not usually associated with the bacteria that cause skin infections. The BAD says diagnosis is usually made from examination, the history and the symptoms you describe.

The NHS says HS can be mistaken for acne or ingrown hairs, and the BAD says it is often misdiagnosed at first as an infection or inflammation of the hair follicles. That can delay treatment and allow scarring to progress, so it is worth asking whether HS has been considered if lumps keep coming back in the same places.

The BAD says HS can contribute to depression and anxiety, and that it is important to speak with a healthcare professional if you feel worried, anxious, embarrassed or unhappy. The NHS also says that living with pain, dressings and discomfort can affect quality of life and lead to depression, and to speak to a GP if you are finding it difficult to cope.

HS is also linked to acne, dissecting scalp cellulitis and pilonidal sinus, and to high cholesterol, high blood pressure and diabetes. The BAD says these do not cause HS but a healthcare professional may check your weight, blood pressure and blood sugar and cholesterol. In some people there is a connection with inflammatory bowel disease such as Crohn's disease or ulcerative colitis, and with inflammatory arthritis. The BAD advises seeking medical attention for persistent diarrhoea, blood in the stools, unexplained weight loss, persistent tummy pain, or persistent joint pain or swelling.

The BAD says the impact of pregnancy on HS varies. In most cases HS is unchanged or improves during pregnancy, although there can be more flares soon after delivery.

Some HS medicines are not suitable if you could become pregnant. The NHS says retinoids such as acitretin cannot be taken during pregnancy and that pregnancy should be avoided for 3 years after stopping them, so they are not usually prescribed if there is a chance you could become pregnant. The BAD notes metformin can be taken during pregnancy. Always tell your dermatologist if you are planning a pregnancy.

See a GP if you have recurring painful lumps in the armpits, groin, bottom or under the breasts, so the cause can be identified early. Ask for a review if lumps are very painful, inflamed and oozing pus, if lumps become infected, if you are finding it hard to cope, or if you notice bowel or joint symptoms.

The NHS says some lumps may become infected with bacteria, causing a secondary infection that needs treating with antibiotics, so ask for a prompt appointment if a lump becomes much more painful, hot or swollen. If you feel very unwell, or are unsure how urgent it is, call NHS 111.

On the NHS, HS is first assessed by a GP, who can start antibiotics and self-care advice. Retinoids and biologic medicines are prescribed by dermatologists, so referral to a hospital dermatology service is needed for moderate to severe disease, as the NHS and BAD describe.

NICE has published guidance for adalimumab (TA392) and secukinumab (TA935) in adults with moderate to severe HS. Some people choose to see a private dermatologist for faster access to assessment. Ask what the plan is for long-term follow-up, who will prescribe repeat medicines and how flares will be handled.