Intra-abdominal abscess in a patient with tumour necrosis factor receptor-associated periodic syndrome.

Tumour necrosis factor (TNF) receptor-associated periodic syndrome (TRAPS) is an autoinflammatory disorder characterized by periodic attacks of fever and inflammation, due to mutations in the gene coding for the TNF type I receptor (TNFRSF1A). A 16-year-old patient with the diagnosis of TRAPS was admitted to hospital because of fever and abdominal pain. Initially, the symptoms were interpreted as manifestations of another TRAPS attack, but the patient's condition worsened, despite treatment with corticosteroids and antibiotics. A repeated computer tomography revealed an intra-abdominal abscess, which necessitated urgent surgical intervention. This case stresses the importance of differential diagnostic vigilance when dealing with patients with rare genetic diseases.

The genetic background of tumour necrosis factor receptor-associated periodic syndrome and other systemic autoinflammatory disorders.

Systemic autoinflammatory disorders are hereditary diseases with symptoms of acute inflammation and a rise in serum acute phase proteins as a consequence, but with no signs of autoimmunity. By the end of the 1990s, four types of hereditary periodic fever had been described in the medical literature: familial Mediterranean fever, hyperimmunoglobulinemia D with periodic fever syndrome (HIDS), tumour necrosis factor receptor-associated periodic fever syndrome (TRAPS) and Muckle-Wells syndrome. Since then, the number of diseases classified as systemic autoinflammatory disorders has increased to eight. In patients of Nordic descent, cases of HIDS and TRAPS have been reported. We provide an overview of the genetic background and main clinical aspects of the different autoinflammatory disorders, with an emphasis on TRAPS.

A novel tumour necrosis factor receptor mutation in a Finnish family with periodic fever syndrome.

OBJECTIVE: To report a novel mutation of the TNF receptor type 1 gene (TNFRSF1A) in a Finnish patient and her mother, both suffering from periodic fever. METHODS: Soluble TNFRSF1A in serum was measured by enzyme-linked immunoabsorbancy, and induced TNFRSF1A shedding from monocyte cell surfaces was determined using fluorescence-activated cell sorter. Mutation detection was performed using PCR amplification and sequencing of the ten exons of TNFRSF1A. RESULTS: Low levels of soluble TNFRSF1A were detected in both patients between attacks. Sequencing revealed a missense mutation in exon 3 in the second extracellular domain of TNFRSF1A, resulting in a substitution of cysteine with arginine at residue 73 (C73R), confirming the diagnosis of TNF receptor-associated periodic syndrome (TRAPS). We were unable to demonstrate a distinct TNFRSF1A shedding defect. CONCLUSION: In patients of Nordic descent, affected by dominantly inherited recurrent fever, TRAPS is a diagnosis worthy of attention. All TNFRSF1A mutations hitherto described in the Nordic countries have been different.