As we approach interview season for our residency program, I try to think of some questions I haven’t asked before. I usually do not discuss dermatologic disorders per se, as I am more concerned about the interviewee as a person knowing how they would mesh in our division. Maybe I’ll make an exception this year. If anyone can explain the enigma of Mucha-Habermann (pityriasis lichenoides et varioliformis acuta) to me, that would go a long way to securing a position. Recently, there has been a flurry of articles about febrile ulceronecrotic Mucha-Habermann disease (FUMHD) that warrant attention.
Admittedly, I have never seen a case of FUMHD; that is fortunate, because it can be a devastating, fatal disease. To date, approximately 70 cases have been reported. It is characterized by the sudden onset of ulceronecrotic skin lesions, with mucous membrane involvement in about 25% of cases, accompanied by high fever and systemic symptoms (abdominal pain, diarrhea, central nervous system symptoms, and sepsis due to secondary infection). FUMHD often starts as classical PLEVA, however, it may present de novo. FUMHD in children tends to have less mucosal involvement but more frequent vasculitis. The prognosis is better in children. The mortality rate of FUMHD is 13%, but there is only one reported fatality in a child (1).
Diagnostic criteria for FUMHD have been proposed by Nofal et al. They suggest that constant features must be present to secure the diagnosis and variable features help to avoid missing the diagnosis. The constant features include: 1) fever; 2) acute onset of ulceronecrotic papules and plaques; 3) a rapid and progressive course without any tendency to spontaneous resolution; and 4) consistent histopathology (parakeratosis, spongiosis, exocytosis, dyskeratosis, vacuolar alteration, a dense perivascular mononuclear infiltrate, extravasated erythrocytes, and a variable component of leukocytoclastic vasculitis). Direct immunofluorescence is non-specific. The variable features are: 1) a prior history of PLEVA; 2) mucous membrane involvement and 3) systemic involvement (2).
The fundamental problem in diagnosing FUMHD is that there are no definitive laboratory studies. The diagnosis is based on the constellation of clinical and histologic features, and ruling out other infectious diseases, such as varicella, or other entities including lymphomatoid papulosis, erythema multiforme, or leukocytoclastic vasculitis. Until the etiology of FUMHD is unraveled, it is unlikely that we will have a definitive test, or an appropriate targeted therapy. The current theories regarding the pathogenesis of FUMHD focus on 1) a hypersensitivity reaction to an infectious agent (e.g., HIV, parvovirus B19, streptococcus, toxoplasma, etc.); 2) an immunologically-mediated vasculitis; and 3) a lymphoproliferative process as part of the spectrum of cutaneous T-cell disorders (3).
Unsurprisingly, there have been no randomized therapeutic trials for FUMHD. Systemic steroids, immunsuppressants, anti-infective agents (antibiotics, dapsone, acyclovir), IVIG, biologics (infliximab) (4), and phototherapy (broad band UVB, narrow band UVB, or PUVA) (5) have all be utilized with varying success. After perusing the literature, I can reasonably conclude that if you want to get Mucha-Habermann mucho mejor, your choice will be methotrexate, either as monotherapy or in combination with one of the other options (6) . It has even proved successful in a 34-month-old boy(7)!
- Nofal A, et al. A fatal case of febrile ulceronecrotic Mucha-Habermann disease in a child. JAAD Case Reports 2016; 2: 181-5.
- Nofal A, et al. Febrile ulceronecrotic Mucha-Habermann disease: proposed diagnostic criteria and therapeutic evaluation. Int J Dermatol 2016; 55: 729-38.
- Alratrout J, et al. Febrile ulceronecrotic Mucha-Habermann disease in an 8 year-old boy responding to methotrexate. Int J Dermatol 55: 1205-9.
- Kreuter A, et al. Complete resolution of febrile ulceronecrotic Mucha-Habermann disease following infliximab therapy. J Dtsch Dermatol Ges 2016; 14: 184-6.
- Maranda EL, et al. Phototherapy for pityriasis lichenoides in the pediatric population: A review of the published literature. Am J Clin Dermatol 2016; 17: 583-91.
- Griffith-Bauer K, et al. Febrile ulcerative Mucha-Habermann disease: Two cases with excellent response to methotrexate. Pediatr Dermatol 2015; 32: e307-8.
- Perrin BS, et al. Febrile ulceronecrotic Mucha-Habermann disease in a 34-month-old boy: A case report and review of the literature. Pediatr Dermatol 2012; 29: 53-8.