Tumor necrosis factor (TNF) receptor-associated periodic syndrome (TRAPS), also known as benign autosomal dominant familial periodic fever and autosomal dominant periodic fever with amyloidosis, is an autoinflammatory disorder classified under the hereditary periodic fever syndromes. It is inherited in an autosomal dominant fashion, although there are reports of autosomal recessive TRAPS. Mutations in the TNF receptor are thought to underlie the pathogenesis, although the link between mutated TNF receptors and the phenotype of this syndrome is not fully understood.

TRAPS was initially described in individuals of Irish or Scottish descent, although it has now been described in a broad range of ethnic groups. There is a slight male preponderance. The onset of TRAPS can occur from 3 weeks to 28 years of age (median age 3 years). In most patients, disease onset occurs before 10 years of age.

Individuals with TRAPS have episodes of fever, abdominal pain (up to 70%), periorbital edema, arthralgias or arthritis, and migratory erythema. Fevers ranging from 38°C-41°C (100.4°F-105.8°F) may precede skin and muscle symptoms. Skin lesions (in up to 85% of affected patients) include erythematous patches and/or plaques with an annular or serpiginous morphology that migrate centripetally, often in association with muscle tenderness. Ecchymotic and purpuric lesions may occur. Other findings may include lymphadenopathy, pericarditis, pleurisy, testicular pain, and inguinal hernias. Lymphadenopathy and periorbital edema are more common in pediatric patients whereas pericarditis is observed more frequently in adult-onset TRAPS.

Attacks occur at random and can last from days to a few weeks, with an average duration of 3 weeks.

TRAPS may improve during pregnancy.

Reactive amyloidosis is a long-term consequence of TRAPS due to deposition of serum amyloid A fibrils in organs including the kidneys, liver, and spleen.

Pediatric Patient Considerations:
In nearly 90% of patients, the first skin eruption is noted during the first 2 years of life.