Acne Conglobata and Rarer Forms of Acne

Acne vulgaris in the form of "teenage spots" is very common in adolescence but other rarer forms of acne may occur. Severe forms of acne can affect many aspects of a person's life, causing a great deal of embarrassment and stress. Severe acne may significantly limit social life and even interfere with opportunities for employment. Rarer variants of acne include:¹

• Acne conglobata: very severe acne in which inflammatory lesions predominate and run together and often form exudates or bleed. Acne conglobata may cause extensive scarring.
• Acne fulminans: sudden, severe inflammatory reaction which causes deep ulcerations and erosions; may be associated with fever and arthralgia.
• Acne excoriée: mainly affects young women and is characterised by self-inflicted wounds associated with a psychological or emotional problem.
• Acne mechanica: caused by pressure, friction or rubbing from clothing.
• Acne cosmetica: caused by contact of comedogenic products with the skin.
• Chloracne: caused by occupational exposure to halogenated hydrocarbons. It presents with many large comedones.

Epidemiology

• Acne conglobata is uncommon and may develop as a result of a sudden deterioration of existing active papular or pustular acne, or may occur as a recurrence of acne that has been inactive for many years.²
• Males are affected more often than females.

Aetiology and risk factors

• The primary cause of acne conglobata remains unknown.
• Changes in reactivity to Propionibacterium acnes (P. acnes) may be important.
• Exposure to halogenated aromatic hydrocarbons such as dioxins or ingestion of halogens may trigger the disease in those who are predisposed.³
• Low oestrogen, high progestogen combined oral contraceptives may cause or aggravate acne.
• Androgen-producing tumours and anabolic steroids used for medical or other purposes may induce severe acne.
• It may appear after testosterone therapy has been stopped.
• There is a tendency for it to run in families and there is an association with certain HLA antigens.

Presentation

Usually presents between 18 and 30 years but may rarely present in infants. Acne conglobata is a chronic and severe form of acne vulgaris showing:

• Deep abscesses
• Inflammation
• Severe damage to the skin
• Scarring
• Comedones (blackheads) which are obvious and widespread, often occurring on the face, neck, trunk, upper arms and/or buttocks
• Inflammatory nodules form around multiple comedones and grow until they break down and discharge pus. Deep ulcers may form under the nodules, producing keloid-type scars, and crusts may form over deeply ulcerated nodules
• Abscesses can form deep, irregular scars
• Acne conglobata may be preceded by acne cysts, papules or pustules that do not heal, but instead rapidly deteriorate. Occasionally, it flares up in acne that had been dormant for many years

Differential diagnosis

• Acne rosacea
• Folliculitis

Investigations

Diagnosis is usually clinical with no investigations required for diagnosis. However, underlying conditions must be considered.

• Total and free testosterone for polycystic ovarian syndrome (PCOS) or ovarian cancer. The androgen producing arrhenoblastoma is rare.
• Serum dehydroepiandrosterone sulfate (DHEAS) for adrenal tumour or congenital adrenal hyperplasia.
• Ratio of LH/FSH for PCOS.
• 17-hydroxyprogesterone for congenital adrenal hyperplasia.
• Prolactin in case of pituitary adenoma.
• 24-hour urinary free cortisol for Cushing's syndrome.
• If isotretinoin is considered, baseline blood tests such as LFTs and fasting lipids are required.

Management²

• There is little evidence that a fatty diet increases the rate of sebum excretion. Regular face washing and the use of antiseptic gels may reduce the amount of P. acnes.
• Emotional support is essential.
• People who have a severe variant of acne should be referred urgently (to be seen within 2 weeks) to a dermatologist.⁴
• People who have severe acne such as painful, deep nodules or cysts (nodulocystic acne), or other people who could benefit from oral isotretinoin should be referred as "soon".⁴

Drugs

• For such severe acne, topical therapy is inappropriate and systemic treatment is essential.⁵
• The therapy of choice is oral isotretinoin.
• Use of systemic steroids with oral isotretinoin may provide additional benefit, especially if systemic symptoms are present.
• Alternatives include oral tetracycline or erythromycin, either alone or with isotretinoin or prednisone.
• Oral contraceptives: Dianette® (ethinylestradiol with cyproterone) may be particularly effective.⁶ Dianette® is an effective contraceptive but it is not licensed as such and the patient should be warned that pregnancy whilst taking this can result in the cyproterone causing ambiguous genitalia in a male fetus.
• Dapsone is recommended for treatment-resistant cases.
• Acne conglobata has been successfully treated by carbon dioxide laser combined with topical tretinoin therapy.
• Infliximab has been tried but not with good results.⁷

Surgery

• Large haemorrhagic nodules may be aspirated.
• Intralesional triamcinolone or cryotherapy may be effective.
• Surgical excision of interconnecting large nodules may occasionally be beneficial.

Complications

• The psychological effect of severe acne on the developing adolescent must not be underestimated.
• Renal amyloidosis has been reported.⁸
• Scars remain for life.

Prognosis

The disease dies down after about 30 years of age but scars remain.

Prevention

There is nothing that can be done to prevent this disease but it needs to be treated energetically to minimise the psychological impact and to reduce scarring.

Acne fulminans is an uncommon, immune systemic disease in which the triggering antigen is thought to be P. acnes.⁹ Acne fulminans predominantly affects young males with a history of acne.

Presentation

• Sudden onset of severe and often ulcerating acne, associated with fever and polyarthritis.
• Acne fulminans causes many inflammatory nodules on the trunk. Large nodules tend to become painful ulcers with surrounding exudative necrotic plaques which become confluent.
• Erythematous neovascular nodules may also be seen.
• Painful splenomegaly, inflammatory arthralgia (especially affects hips and knees),¹⁰ bone pain, erythema nodosum and chronic aseptic multifocal osteomyelitis may be present.

Investigations

Abnormal findings include:

• Full blood count: anaemia, leucocytosis (with increased polymorphs)
• Raised ESR
• Circulating immune complexes
• Proteinuria
• X-rays: approximately 50% of patients have lytic bone lesions. Destructive lesions resembling osteomyelitis may be seen.
• Technetium scintillography: multifocal osteolytic cysts may be detected as hot spots.

Differential diagnosis

• Acne conglobata
• Acne vulgaris
• Acneiform eruptions
• Pyoderma gangrenosum

Management

• Oral steroids should be started and gradually reduced over 6 weeks.
• Oral isotretinoin should be started after 4 weeks and gradually increased to achieve complete clearance.
• Response to broad-spectrum antibiotic treatment is poor.
• Infliximab may be used if other treatments are ineffective.
• Pulsed dye laser is effective for granulation tissue associated with acne fulminans.

Prognosis

• Recurrence of acne fulminans is rare.
• Scarring and fibrosis may occur.