What Is Acne Fulminans?

Acne fulminans (AF), also known as acne maligna, is a type of acne first described in 1959 and later named in 1975.¹ However, this form of acne is rare, with fewer than 200 cases reported worldwide.² It was named fulminans to characterize the sudden and severe onset of the disease.¹ AF is usually found in Caucasian teenage males, aged 13-22 years old. It often presents within two years following onset of acne vulgaris.³

The disorder may initially resemble acne conglobata, however the rapid formation of hemorrhagic nodules and plaques that quickly ulcerate leaving painful necrotic ulcers distinguishes AF.¹ In addition, unlike acne conglobata, AF may present with systemic symptoms including fever, polyarthritis, malaise, osteolytic bone lesions, and failure to respond to antibiotic therapy.¹

Etiology and Pathogenesis

The exact etiology of acne fulminans is still unknown. Reported cases have been associated with initiation of high dose oral isotretinoin use, as well as increased testosterone levels and anabolic steroid use.^3,4 It may also have a genetic association with reports of affected monozygotic siblings.³ There is also evidence indicating that the condition may be autoimmune mediated.^1,3 It has been suggested that AF may be triggered by an exaggerated response to C. acnes in susceptible individuals, over activating inflammasomes causing the release of high levels of IL-1 and TNF-alpha.³ However, further research needs to be conducted to further delineate the etiology and pathogenesis of AF.

Classification

Acne fulminans can be classified into four variants^3,5:

• Acne fulminans with systemic symptoms (AF-SS)
• Acne fulminans without systemic symptoms (AF-WOSS)
• Isotretinoin-induced acne fulminans with systemic symptoms (IIAF-SS)
• Isotretinoin-induced acne fulminans without systemic symptoms (IIAF-WOSS)

Associated Syndromes

Acne fulminans can also be associated with other inflammatory syndromes.

Diagnosis and Tests

Acne fulminans usually has an acute onset, characterized by severe, necrotic, ulcerating acne (Figure 1).⁶ The acne can evolve into painful nodules and necrotic ulcerations that can lead to extensive scarring. The acne can present on the face, neck, chest, and back.⁷ Previous history is also important as acne fulminans can be associated with initiation of high dose oral isotretinoin and anabolic steroid use.^3,4 Additionally, previous severe acne refractory to antibiotic use can be another factor associated with acne fulminans.

Figure 1: Hemorrhagic ulcerating lesions with purulent crust in Acne Fulminans prior to treatment⁶

Associated symptoms include:^3,4,7

• Fever
• Painful splenomegaly
• Erythema nodosum
• Bone pain
• Joint pain (leading to painful, bent-forward gait)
• Myalgia

Tests used to diagnose the condition include:^2,5

• Complete blood count with elevated white cells
• Elevated erythrocyte sedimentation rate
• Elevated C-reactive protein
• X-ray showing lytic lesions

Treatment

There is currently no standardized guideline for AF treatment as there is a lack of randomized controlled trials. Due to the rapid and devastating effects of AF, patients should be referred to a dermatologist for management.

Current treatment recommendations include a tapered course of high-dose oral corticosteroids and subsequent addition of oral isotretinoin.^3,5 Corticosteroids initiation helps to control the inflammation, and should be continued as a monotherapy for 2-4 weeks, or until crusted lesions heal. After 4 weeks, isotretinoin can be added for stabilization of keratinization and sebaceous gland differentiation.^3,5 However, in cases that may have been precipitated by oral isotretinoin, the drug should be immediately suspended, and attempts to slowly re-add isotretinoin should be made after disease stabilization is achieved with corticosteroids.

The use of biologic TNF-alpha inhibitors, such as etanercept and infliximab, are an emerging treatment modality that has led to clinical responses in some resistant patients.^3,5 Alternatively, cyclosporine and dapsone have been used in several case reports.⁴ Since acne fulminans is generally non-responsive to antibiotics, treatment should avoid tetracyclines. However if patients experience side effects associated with isotretinoin or corticosteroids, high dose tetracyclines may be attempted.⁵ Use of topical corticosteroids in addition to a systemic treatment may lead to a faster response.⁵ Pulsed-dye lasers have also proved efficacious for treating acne scarring.⁵

While AF onset is rapid, resolution is often gradual and can result in significant scaring and skin disfigurement (Figure 2).⁶ This can result in psychological distress and depression. Follow up with a psychiatrist is recommended to monitor and treat any secondary psychological conditions.² Other long-term sequalae of AF are rare.¹ If patients are adherent to their treatment regimens, there is generally no recurrence of disease.^1,7

Figure 2: Acne Fulminans 28 days after treatment initiation⁶

Case Studies

As acne fulminans is a rare disorder, affecting fewer than 200 people worldwide, many reports on acne fulminans are case studies focused on single patients. Below we’ve documented several case studies on acne fulminans.

31-year-old male bodybuilder⁸

This individual recently began intramuscular testosterone injections in preparation for a bodybuilding competition. He began developing severe acneiform lesions as well as having difficulty moving and sleeping. These lesions were found on his face, chest, back and arms, specifically on his shoulders, arms, and upper back. He responded well to prednisone, doxycycline, antihistamines, and isotretinoin, and slowly began to heal. In this case, the acne fulminans was most likely caused by the testosterone injections, which increased sebaceous gland secretions as well as increased C. acnes populations.

15-year-old male teenager⁹

This individual began with a six-month history of acne vulgaris that recently worsened over two weeks. Additionally, he presented with a fever of 100.4˚F with joint, spine, and knee pain. Both his acne symptoms and his systemic systems worsened after treatment with oral tetracycline and topical benzoyl peroxide. However, treatment with prednisone improved symptoms.

21-year-old male⁹

This patient did not have a previous history of acne as a teenager but presented with lesions that had rapidly progressed to suppurative nodules. He also had symptoms of high fever and joint pain. None of the symptoms had been responsive to antibiotics. After being prescribed prednisone and “usual acne treatment,” he improved but retained scarring.

Key Takeaways

• Acne fulminans is a severe form of acne that typically affects Caucasian males aged 13-22-years-old.
• It can be brought on by steroid, testosterone, or isotretinoin use, and it may have a genetic or autoimmune component.
• It is best treated with oral corticosteroids and isotretinoin—if the isotretinoin doesn’t worsen the acne. Newer forms of treatment like etanercept and infliximab have also proved efficacious.