Acne Fulminans

Etiology

Acne fulminans is a rare skin disorder, and hence its etiology is not well understood. Acne fulminans may be triggered by the use of high doses of isotretinoin when initiating treatment in patients with severe acne. Also, elevated levels of testosterone may have a role in the pathogenesis. Anabolic steroids are known to increase levels of sebum and density of Propionibacterium acnes. Bodybuilders who use anabolic steroids develop acne fulminans within a very short time. The belief is that the density of P. acnes or related antigens triggers the immune system and leads to acne fulminans. Others believe the condition to be autoimmune-mediated because circulating immune complexes have appeared in some patients with acne fulminans.[4][5]

Acne fulminans also has a genetic component, but the pattern of inheritance is not known. The skin disorder may be part of the synovitis, acne, pustulosis, hyperostosis, and osteitis syndrome (SAPHO), pyogenic arthritis, pyoderma gangrenosum, and acne syndrome (PAPA), pyoderma gangrenosum, acne, and hidradenitis suppurativa syndrome (PASH), and pyogenic arthritis, pyoderma gangrenosum, acne, and hidradenitis suppurativa syndrome (PAPASH).

Epidemiology

Less than 200 cases are known. The disorder usually affects young males, mainly of the White race, between 13 and 22 years of age. Most of these males have a prior history of acne. There also are isolated reports of acne fulminans in females. There are globally-reported cases of this condition, but its incidence seems to be declining.

History and Physical

Acne fulminans usually has a very sudden onset, and the acne often is ulcerating. Patients may complain of fever and pain in multiple joints. They typically provide a history that the conventional antibiotics used for treating acne did not work. Most patients mention that they did have acne in the past.

Acne fulminans is similar to acne conglobata with numerous inflammatory nodules on the trunk. The nodules often are painful to touch, ulcerated, hemorrhagic, and covered with crusts. Unlike acne conglobata, there are cysts and acutely inflamed lesions, but there are no polyporous comedones. Painful splenomegaly and erythema nodosum may be associated with systemic symptoms.

Patients with acne fulminans who have systemic symptoms may have a stooped posture due to bone and joint pain. The inflammatory arthralgia usually affects more than one joint, typically the knees, hips, and pelvis.

Evaluation

Because the disorder may be associated with systemic symptoms, the workup should include the following:

• Complete blood cell count (CBC); may show elevated white blood cell (WBC) count with a large percentage of neutrophils, anemia of chronic disease, and/or leukemic-type reaction
• Erythrocyte sedimentation rate (ESR) and C-reactive protein may be elevated
• Liver function test
• Human chorionic gonadotrophin (blood or urine) in female patients

Imaging

Because of bone and joint pain, imaging frequently is done. In the early stage, X-rays will only show reactive changes. About 50% of patients will demonstrate lytic lesions on a plain film X-ray, and the bone scan may show multiple areas of increased uptake. The lesions are destructive and often resemble acute osteomyelitis. Cultures of these bony lesions are often negative.

Treatment / Management

The recommended treatment for acne fulminans is a combination of corticosteroids and isotretinoin. Oral corticosteroids should be started first at high doses (0.5 to 1 mg/kg/day) for at least two weeks (at least four weeks if systemic symptoms) until lesions heal. Isotretinoin therapy can then start. The initial dose of isotretinoin should be 0.1 mg/kg/day in association with corticosteroids for four weeks. If there is no observable flare, maintain the same dose of isotretinoin for four more weeks, and corticosteroid doses should undergo gradual tapering. Increasing isotretinoin doses should then progressively reduce to a minimum total dose of 120 mg/kg.[6][7][8][9](B3)

In patients who remain adherent, relapses are rare. If a relapse does occur, a repeat cumulative dose of isotretinoin at 150 mg/kg is the recommendation. The treatment with isotretinoin lasts for many months as the initial dose is low.

A recent review suggests that the use of additional high-potency topical corticosteroids may result in a faster response. Once healing occurs, the lesions become smaller, less tender, and have a minimal inflammatory reaction. Scarring is common.

Acne fulminans does not respond to the traditional antibiotics used to treat the typical form of acne. Even when using these agents, the response is slow and incomplete.

In the last few years, anecdotal reports have appeared after the use of biologics, such as etanercept and infliximab, in resistant patients. The response to these agents is effective and rapid. However, it is unknown if biologics will work in all patients. Several other targeted biologics also have been used to treat acne fulminans.

Other Treatments

Pulsed dye laser has shown moderate effectiveness, but adverse effects and pain remain an issue. Because the lesions are large, multiple treatments are required, and scarring and hypopigmentation are common complications.

Reports suggest that diaminodiphenyl sulfone use may help ease the symptoms of acne fulminans in patients with ulcerative colitis.

Combinations of prednisone with dapsone or cyclosporine also have been tried with success.

Finally, the management of these patients is best with a dermatologist and an internist. Women of childbearing age should use great caution when using retinoids, as these agents are teratogenic. There is a registry of all patients who receive retinoids. All women who receive therapy with isotretinoin should avoid getting pregnant for at least one month after discontinuing the drug.

Differential Diagnosis

• Acne and suppurative hidradenitis ( PASH) syndrome

• Acne conglobata

• Acne vulgaris

• Bromoderma

• Folliculitis decalvans

• Iododerma

• Rosacea fulminans

• Severe cystic acne