[Severe systemic vasculitis induced by ibrutinib]. / Vascularite systémique sévère induite par l'ibrutinib.

INTRODUCTION: The specific cutaneous toxicity of Bruton's tyrosine kinase inhibitors is poorly described. We report a case of severe systemic vasculitis induced by ibrutinib. OBSERVATION: A 73-year-old woman with chronic lymphocytic leukemia was treated with ibrutinib. Eighteen months after treatment onset, ulceronecrotic lesions on toes and tongue occurred. Skin biopsy found vasculitis of small and medium vessels. Biologic tests were negative. This vasculitis was refractory to systemic corticosteroid therapy and azathioprine. Ibrutinib was stopped on the hypothesis of drug-induced vasculitis. Skin lesions improved after discontinuation of ibrutinib. CONCLUSION: The mechanism of action of ibrutinib does not explain the occurrence of vasculitis and an immunoallergic mechanism is suspected.

[Cutaneous, mucosal and systemic pyoderma gangrenosum]. / Pyoderma gangrenosum cutanéomuqueux et systémique.

BACKGROUND: Extracutaneous and mucosal involvement is rare in neutrophilic dermatoses. We report a case of cutaneous-mucosal and systemic pyoderma gangrenosum (PG) revealing myelodysplasic syndrome. CASE REPORT: A 56-year-old man was hospitalised for an inflammatory abdominal plaque with an ulcerated centre that appeared rapidly in a setting of fever of 40 degrees C, odynophagia, weight loss and arthritis of the ankle. Despite surgical abdominal repair and combined dual antibiotics, the patient remained febrile and the ulcer size continued to increase. The edges were raised, purple and necrotic. Examination revealed vegetative legions with a purple edge on the lower lip and tongue. Histological examination of the skin and mucosal biopsy samples was consistent with a diagnosis of PG. A chest-abdomen CT scan showed mesenteric panniculitis and interstitial lung disease. The bone marrow sample revealed an appearance of chronic myelomonocytic leukaemia with myelofibrosis and excessively high blast levels. Systemic corticosteroids rapidly resulted in apyrexia with healing of the cutaneous, mucosal and visceral lesions. The patient presented secondary worsening of his acute myeloid leukaemia type-IV requiring bone marrow rescue. DISCUSSION: Extracutaneous involvement in neutrophilic dermatoses is rare but takes a number of different forms. We report a case of a patient presenting multifocal PG with cutaneous, mucosal, joint, mesenteric and pulmonary involvement. Oral lesions seen in PG generally affect the palate and they are commonly associated with inflammatory intestinal diseases. Our case is original in terms of the inaugural character of the mucosal lesions, their burgeoning appearance and their location on the lips and tongue.