Acute febrile neutrophilic dermatosis (Sweet's syndrome) in childhood and adolescence: two new patients and review of the literature on associated diseases.

Objectives: The objectives of this study were to analyse the literature on Sweet's syndrome in childhood focussing on associated diseases and to suggest possible screening procedures for this group of patients. Furthermore, two new patients with Sweet's syndrome are reported.

Methods: A literature search was performed on Pub med using search terms "sweet* syndrome*" and neutrophil* dermatos*. Patients were subdivided into the following groups: classic/idiopathic, paraneoplastic, and parainflammatory Sweet's syndrome.

Results: The literature search revealed 64 patients (including our two patients) who were diagnosed with Sweet's syndrome in childhood and adolescence; 27 (42%) patients were categorized as "classic/idiopathic Sweet's syndrome". In 37 patients (58%) chronic associated diseases were reported. Out of these, 21 (33%) patients were categorized as "parainflammatory Sweet's syndrome" including chronic recurrent multifocal osteomyelitis, vasculitis with aortitis, recurrent infections due to immunodeficiencies, arthritis, and systemic lupus erythematosus. Sixteen (25%) patients were categorized as "paraneoplastic Sweet's syndrome" comprising both malignant and premalignant diseases like leukemia, aplastic anaemia, and Fanconi anaemia. As all five (8%) patients treated with drugs (granulocyte-colony stimulating factor, retinoid acid) suffered from malignant, premalignant, or parainflammatory diseases, these patients were categorized according to the underlying disease. Two new children with Sweet's syndrome and associated diseases are presented here, one of them suffering from recurrent infections and trisomy 21, while the other was diagnosed with CNS vasculitis 5(1/2) years after the primary diagnosis.

Conclusions: Sweet's syndrome should be considered in differential diagnosis of prolonged fever with cutaneous involvement. As most cases of pediatric Sweet's syndrome are associated with other diseases we suggest careful screening and monitoring of these patients especially concerning malignant/premalignant diseases, immunodeficiencies, cardiovascular involvement, autoimmune diseases, and drug associations.