TRAPS
Tumour Necrosis Factor Receptor Associated Periodic Fever Syndrome
(aka Familial Hibernian Periodic Fever Syndrome) Genetic Testing
Test Information/Clinical Significance
The test is useful for the confirmation of the diagnosis of TRAPS in patients with relevant clinical features, and may also be useful in differentiating causes of periodic fever, in genetic counseling and in prenatal diagnosis.
TRAPS usually presents in childhood. Patients may experience fevers that last from a few days to several weeks (a longer term than seen with FMF). Abdominal symptoms are common and include pain, diarrhoea, constipation and, occasionally, peritonitis. Pleurisy and pericarditis may occur, as well as painful joints, muscle pain, conjunctivitis, and painful migratory erythematous skin lesions. Laboratory markers of inflammation are common.
Occasionally, patients with periodic fever may have mutations in other proteins resulting in Familial Mediterranean Fever, the Muckle Wells Syndrome or Familial Cold Urticaria Syndrome.
Method
Testing involves bi-directional sequencing of exons 2, 3 and 4. All mutations except one have been described within these exons that code for the intracellular domain of the TNF receptor. Additional sequencing of the TNFRSF1A gene is available after consultation.
Genetic Counselling
Genetic counselling is an essential aspect of testing for all genetic disorders and should be offered to patients prior to referral for testing and for discussion of test results.
Specimen
5 mL EDTA (dedicated tube required)
Results Availability
Test is performed weekly