AB1087 Prolonged response with tumour necrosis factor alfa inhibition in a 5 year old boy with severe manifestations of il-36 receptor antagonist deficiency (DITRA)

Background Deficiency of the interleukin (IL)−36 receptor antagonist (DITRA) is an autosomal recessive autoinflammatory syndrome caused by mutations in the IL36RN gene. Clinical manifestations of DITRA include recurrent episodes of generalised skin postulation, fever, systemic inflammation and leukocytosis. An uniformly effective treatment for DITRA has not yet been identified. Objectives We present a case of a 5 year old patient with DITRA with prolonged response with tumour necrosis factor alfa inhibition with adalimumab. Methods A five-year-old came to our dermatology clinic after worsening of a previous diagnosed plaque psoriasis, with an erythematous scaly dermatitis that extended throughout the trunk. Treatment with acitretin and cyclosporin were not effective and patient developed in few weeks a generalised erythroderma with pustules covering almost every part of his body, including palms and soles. He was admitted for the onset of fever and irritability due to painful rubbing of the skin. Family history of recurrent fevers or psoriasis were not revealed. Parents were not consanguineous. Complete blood count showed leukocytosis with neutrophilia and thrombocytosis, with an erythrocyte sedimentation rate (ESR) of 6 mm/hr and a C-reactive protein (CRP) of 8,4 mg/dl. Biochemistry panel revealed a mild elevation of liver enzymes without other abnormalities. Antinuclear antibody (ANA) and rheumatoid factor were negative with normal serum immunoglobulin and complement. Blood culture grew E. Coli, S. Maltophila and S. epidermidis. Skin biopsy showed acanthosis and papillomatosis with perivascular polymorphous inflammatory cells. Genetic analyses showed a homozygous mutation in the IL36RN gene (pSer113Leu). No mutations were detected in IL1RN and CARD 14 genes. Results Treatment was initiated with intravenous methylprednisolone 2 mg/kg/day and subcutaneous anakinra 2 mg/kg/day. Cefotaxime and co-trimoxazole were added until blood cultures were negative. Although skins lesions improved during the following days and patient was finally discharged, symptoms reappeared when decreasing the steroid dose. Three months later adalimumab and methotrexate were started, allowing the patient to end treatment with corticoids without evidence of activity of the disease. Conclusions After incomplete response with anakinra, inhibition of tumour necrosis factor alfa resulted in a prolonged response in our patient with deficiency of the interleukin (IL)−36 receptor antagonist (DITRA). Disclosure of Interest None declared