RESUMEN
BACKGROUND: TNF receptor-associated syndrome (TRAPS) is a dominantly inherited autoinflammatory condition caused by mutations in the TNFRSF1A gene. The mechanism underlying the variable expressivity of the common variant R92Q (rs4149584; c.362G>A; p.Arg121Gln) is unclear and is of critical importance for patient care and genetic counseling. This study evaluated the impact of the number of R92Q mutations in two unique unrelated families. METHODS: Two patients with undefined but clear autoinflammatory symptoms were referred for genetic diagnosis. Blood samples were collected from the available family members to screen autoinflammatory genes and assess key steps of the TNFR1-mediated signaling pathway using flow cytometry and ex vivo culture. RESULTS: R92Q homozygosity was demonstrated for the two probands. In family 1, the segregation analysis revealed TRAPS-like symptoms in all carriers, with a more severe presentation in the proband, whereas in family 2, the heterozygous parents were totally asymptomatic, suggesting recessive transmission. Functional studies revealed a nonclassical pathogenesis of TRAPS in the two probands and suggested a compensatory mechanism without clear dose effect. CONCLUSION: We observed for the first time a possible clinical dose effect of R92Q. This work highlights the importance of familial studies to reconcile the contradictory reports published on the pathogenicity of this variant.
RESUMEN
Orbital tumor lesions in pediatric population encompass a wide range of pathological processes, which are very different in etiology and prognosis. They usually require an emergency in histological diagnosis because of their quick growth. Beside malignant and benign tumors, the inflammatory pseudo-tumors group included dysimmune orbital involvement secondary to systemic vasculitis such as granulomatosis with polyangiitis (ex-Wegener's granulomatosis). We report the case of a seven-year-old girl suffering from a severe primitive ANCA vasculitis, revealed by an orbital mass.