[TRAPS: clinical significance of genotype. A report of two cases]

Tumor necrosis factor receptor associated periodic fever syndrome (TRAPS) is defined as recurrent attacks of generalized inflammation for which no infectious or auto-immune cause can be identified; it is caused by dominantly inherited mutations in the gene encoding the first TNF receptor. We report two additional cases of patients with TRAPS, suggesting that mutation pattern of TNFRSF 1A gene may influence the TRAPS phenotype.

The first patient, with a C30S mutation, exhibited severe digestive clinical manifestations; because the patient required high-dose corticosteroids regimen to improve TRAPS manifestations, he was further given successfully etanercept. The second patient, with a R92Q mutation of TNFRSF 1A gene, presented with moderate symptoms; TRAPS outcome was favourable after corticosteroid therapy initiation.

Therefore, R92Q may be associated with a mild disease phenotype. On the other hand, C30S mutation appears to be associated with a severe phenotype, leading to an increased risk of amyloidosis. These findings suggest that these latter patients may require a closer follow-up.