Deficiency of Interleukin-1 Receptor Antagonist: New Genetic Autoinflammatory Disease as a Diagnostic Challenge for Pediatricians.

Deficiency of interleukin-1 receptor antagonist is a rare autoinflammatory disease that affects infants early in life. It often presents with systemic inflammation, skin and bone involvement. We present a 5-month-old boy who was hospitalized due to generalized erythematous pustular eruption with secondary impetigo, cellulitis, bronchiolitis, and elevated inflammatory markers. The patient was unresponsive to multiple courses of intravenous antibiotics, systemic, and topical steroid medications. The patient was evaluated by dermatology and rheumatology services among other subspecialities. Skin biopsy showed changes consistent with psoriasiform dermatitis, while bone scans showed multifocal osteomyelitis. The patient was started empirically on anakinra with improvement at 72 hours upon administration. This is one of the youngest reported case in the literature to be started on anakinra empirically prior to genetic confirmation of the mutation. A comprehensive literature review revealed that approximately 20 genetically confirmed patients, including our patient, have been reported with this genetic disease. It is imperative to recognize this disease early to achieve adequate response and remission. Therefore, clinical symptoms and the associated differential diagnosis for this disease should be constantly reassessed and reviewed by pediatricians and subspecialists to detect the disease as early as possible and reduce the high morbidity and mortality associated with delayed diagnosis and treatment.