Acute Febrile Neutrophilic Dermatosis (Sweet Syndrome) Onset in a Child After COVID-19: Case Study

Background. Sweet syndrome is a rare inflammatory disease from the group of neutrophilic dermatoses, characterized by proinflammatory cytokines hyperproduction. Case description. A child, 1 year 3 months old, with referral diagnosis of “Pyoderma gangrenosum” was diagnosed: «Acute febrile neutrophilic dermatosis. Sweet syndrome». Molecular genetic testing was carried out to clarify the diagnosis: whole-exome sequencing of venous blood from the patient and his mother. As a result both of them had nucleotide variant c.3061C>T in exon 26 of the UBA1 gene. Step-up therapy with methylprednisolone, dapsone, tofacitinib, anakinra, and ruxolitinib was administered due to pathological skin process severity, high interleukins 1 and 6 levels, and according to the experience in management of such patients described in medical literature. Sustained remission of the skin pathological process was noted on treatment. Conclusion. Case study of acute febrile neutrophilic dermatosis (Sweet syndrome) is presented. Results of successful drug therapy are shown.

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