Tumour necrosis factor receptor-associated periodic syndrome (TRAPS) is a dominantly inherited disorder characterised by recurrent episodes of sustained fever. Here we report a case of TRAPS with a novel TNFRSF1A mutation, C70S, in a Japanese family. The mutation disrupts one of the three disulphide bonds in cysteine-rich domain 2 of TNF receptor 1, similar to the reported mutations of the same cysteine residue (C70R, C70Y). This is the first confirmed case of TRAPS in an eastern Asian population. The patient's asymptomatic sister as well as their mother with mild symptoms had the same mutation.
Conclusion: Although tumour necrosis factor receptor-associated periodic syndrome has been reported mainly in families of northern European ancestry, our case suggests the need to include it in the differential diagnosis of patients with recurrent fever even in ethnic groups in which no case has been documented.