Erythema nodosum (EN) is a form of septal panniculitis, which is believed to represent a delayed hypersensitivity reaction activated by infectious agents, drugs, granulomatous and autoimmune diseases, pregnancy, and malignancies. There are only four reported cases of EN during oral isotretinoin therapy to our knowledge, all of them occurring in patients with severe acne. Since acne itself can trigger EN, the question as to whether there is indeed a causative relationship between isotretinoin and EN in the reported cases remains to be elucidated. We present herein a 20-year-old woman with multiple vulvar condylomata acuminata who developed EN two weeks after onset of oral isotretinoin therapy. To the best of our knowledge, this is the first report of EN occurring during isotretinoin treatment in a patient without acne and strongly indicates that the pathogenesis of EN can be directly related to the biological actions of isotretinoin. Erythema nodosum should be regarded as a rare side effect of oral isotretinoin therapy, regardless of the underlying disease. Physicians should be aware of this rare side effect.

Erythema multiforme is an immune-mediated cutaneous disorder that is thought to represent a hypersensitivity reaction to infections, drugs, vaccines, malignancies, autoimmune diseases, radiation, and menstruation. Golimumab is a human IgG1-kappa anti-TNF antibody that has been approved for the treatment of rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, and ulcerative colitis. We report herein a 41-year-old woman with persistent erythema multiforme, that occurred 18 months after onset of golimumab treatment of her ulcerative colitis; the latter remains in full remission over a period of 36 months.

The popularity of tattoos has increased dramatically worldwide particularly in the last three decades, giving rise to the frequent occurrence of a wide spectrum of secondary cutaneous and systemic complications. Pseudoepitheliomatous hyperplasia (PEH) is a benign irregular hyperplasia of the epidermis occurring in response to various stimuli, that clinically and histopathologically resembles cutaneous neoplasms such as squamous cell carcinoma and keratoacanthoma. In an attempt to improve the awareness of the possible occurrence of PEH in tattoos and of its diagnostic and therapeutic aspects, we present herein the case of a 30-year-old woman with histologically confirmed PEH related to a red-ink tattoo. She revealed two important features: the longest interval reported so far between tattooing and onset of PEH (two years) and the lack of the otherwise very common lichenoid tissue reaction to red ink. In view of the serious toxicological potential of tattoo inks, implementation of updated and standardized regulations worldwide regarding their use in the tattooing process is now urgently warranted and continuous efforts should be undertaken in order to enhance the awareness among tattoo artists and the public with regard to the possible serious health risks associated with the use of tattoo ink pigments.

Eosinophilic pustular folliculitis (EPF) is a rare noninfectious pruritic dermatosis, first described by Ise and Ofuji in 1965. We report the case of a 15-year oldimmunocompetent girl that presented with a widespread papulopustular eruption four days after her arrival in Japan. The clinical diagnosis of the classicform of EPF was confirmed by histological examination of the lesional skin that revealed an intense, mainly eosinophilic, dermal infiltrate within and aroundpilosebaceous units. Oral administration of lowdose indomethacin (25 mg/day) led to a complete resolution of the eruption within 6 weeks without causing any side effects. The patient is presently completing a 15-month follow-up and remains free ofrelapses. To the best of our knowledge, it is the first time that low-dose oral indomethacin is reported to be capable of causing a rapid and complete resolutionof the classic form of EPF.

Grover disease (GD) is a disorder of unknown origin, clinically characterized by the occurrence of pruritic, erythematous or brownish papules and papulovesicles, which histologically reveal four different patterns of acantholysis. Usually, the eruption is self-limited and spontaneously remit within a few weeks. In some cases, however, it may persist for months or even years and show a therapy-resistant course. We report a 56-year-old woman with recalcitrant, persistent, and generalized GD who showed complete remission after 6 weeks of treatment with oral acitretin (0.8mg/kg/day). The treatment was well-tolerated and laboratory parameters remained unchanged. The patient remains free of any recurrence at 26 months. To the best of our knowledge, this is the first report of a complete remission of the persistent form of GD as a result of oral acitretin monotherapy.