Acne conglobata: a severe form of acne and how it is treated

The NHS describes acne as a common skin condition that can range from a few spots to deep, painful lumps under the skin. At the severe end are nodules and cysts, which the NHS says are larger lumps that may join together and can be painful. Acne conglobata is one of the most severe forms.

DermNet, a dermatology reference from New Zealand (there is no UK patient page on this specific condition), describes acne conglobata as a rare severe variant of nodulocystic acne. It presents with groups of multiple comedones and inflammatory papules, pustules and nodules involving the trunk, limbs and buttocks, with interconnecting abscesses and draining sinuses that become secondarily infected. The MSD Manual describes it as the most severe form of acne vulgaris.

DermNet says nodulocystic acne is usually a disorder of adolescence and early adult life, seen most commonly in males. It notes risk factors for nodulocystic acne including genetic factors, drugs such as anabolic steroids, etanercept and imatinib, dietary supplements such as whey, and haemodialysis. The MSD Manual says acne conglobata affects men more than women.

DermNet also notes that nodulocystic acne is associated with other follicular occlusion disorders, particularly hidradenitis suppurativa, and that the acne conglobata variant forms part of a number of syndromes with names such as SAPHO, PASH, PASS and PAPA. Severe acne with other symptoms is therefore something to raise with a specialist.

Because of the scarring, DermNet says unless nodulocystic acne is treated early and effectively it results in scarring, particularly on the torso. Healing is slow, and the condition often persists into adult life.

• Groups of blackheads (comedones) alongside inflamed spots, pustules and deep nodules.

• Involvement of the trunk, limbs and buttocks, not just the face.

• Interconnecting abscesses and draining sinus tracts that can become infected, painful and malodorous.

• Slow healing, leaving thick (hypertrophic) and thinned (atrophic) scars.

• In skin of colour, post-inflammatory hyperpigmentation and keloid scarring are common complications, according to DermNet.

• Effects on mood and confidence: the NHS notes that acne can cause anxiety, depression and low self-esteem.

The NHS advises seeing a GP for acne if treatments you have tried yourself are not working, if you have lots of spots, or the spots are deep, painful or causing scars, if there are signs of skin infection such as hot, swollen, red skin, or if it is affecting your mental health. A GP may offer prescription treatments or refer you to a skin specialist (dermatologist).

Deep, interconnected lumps with discharge are the kind of acne for which early referral to dermatology is sensible, since DermNet says isotretinoin should be started early to prevent scarring. If low mood or distress is significant, tell the doctor, as the NHS says acne can affect mental health.

DermNet says nodulocystic acne is a clinical diagnosis, meaning it is made from the appearance and history rather than a specific test. Hormone studies may be considered when there are suggestive clinical features. DermNet lists acne fulminans, pyoderma faciale and steatocystoma multiplex among conditions that can look similar.

DermNet says topical treatment is usually ineffective for nodulocystic acne and the recommended treatment is oral isotretinoin, started early, for at least five months, with further courses sometimes necessary. Intralesional steroid injections after cyst drainage can be used for individual large nodules. Patients with acne conglobata often need additional treatments such as oral antibiotics for secondary infection, systemic corticosteroids to reduce inflammation, and adalimumab, used off-label, for resistant severe disease. The MSD Manual says acne conglobata is treated with oral isotretinoin and systemic glucocorticoids if severe and if systemic antibiotics fail.

The NHS lists isotretinoin among treatments available from a GP or skin specialist, and says prescription treatments are stronger than pharmacy products. In the UK, isotretinoin is specialist-supervised. The British Association of Dermatologists explains that it is licensed to treat severe acne in people over 12 when other treatments have not worked or there is a risk of permanent scarring.

The British Association of Dermatologists says most people find isotretinoin helps their acne and for many can clear their skin, with acne staying better for several years after finishing in most people. There is a possibility that acne gets worse for a few days or weeks before it starts to get better. DermNet notes that acne conglobata is often very persistent and that further courses are sometimes necessary.

The NHS suggests washing your skin twice a day with a gentle cleanser. Avoiding picking or squeezing spots (which the NHS says can cause scars), and seeking mental health support if you need it are all reasonable steps alongside medical treatment.

On the NHS, severe acne is usually first assessed by a GP, who may start treatment and refer to a dermatologist. Isotretinoin is prescribed by dermatology specialists, with blood tests and regular follow-up, as the leaflet explains.

Some people see a private dermatologist for faster access. The safety advice in the British Association of Dermatologists leaflet applies in either setting. Ask who will monitor you, how often tests are needed and how scars would be managed afterwards.