TNF receptor associated periodic syndrome

TNF receptor associated periodic syndrome (also known as TRAPS, Tumor necrosis factor receptor associated periodic syndrome or familial Hibernian fever) is a periodic fever syndrome associated with mutations in a receptor for the molecule tumor necrosis factor (TNF) that is inheritable in an autosomal dominant manner. Individuals with TRAPS have episodic symptoms such as recurrent high fevers, rash, abdominal pain, joint/muscle aches and puffy eyes. TRAPS was first described in 1982 in a boy of Scottish-Irish origin. At that time, it was named familial Hibernian fever.

The main source of TNF (tumor necrosis factor) is cells in the immune system called macrophages which produce it in response to infection and other stimuli. TNF helps activate other immune cells and plays a major role in initiation of inflammation. Individuals with TRAPS have a mutation in the tumor necrosis factor receptor-1 (TNFR1) gene. The mechanisms by which mutations in TNFR1 lead to the TRAPS phenotype are still under investigation. Impaired shedding of the TNF receptor is one of the possible defects. Most mutations affect the extracellular domain of the receptor, some also the cleavage site.

Several medications have been studied for the treatment of TRAPS including etanercept, infliximab, tacrolimus and Il-1Ra (anakinra). Studies on treatment efficacy in a larger group of patients affected with TRAPS are however lacking to date.