- TUMOUR NECROSIS FACTOR RECEPTOR ASSOCIATED PERIODIC SYNDROME (TRAPS).

TUMOUR NECROSIS FACTOR RECEPTOR ASSOCIATED PERIODIC SYNDROME

(TRAPS)

INCIDENCE/AETIOLOGY

It occurs in many ethnic groups with presentation in the 1st decade of life.

TRAPS is caused by AD, gene mutations in TNFRSF1A on chromosome 12.

Clinical Manifestations:-

Attacks are often far less distinct than in FMF, precipitated by minor stress, travel, menstrual cycle or diet.

Prolonged attacks occur, lasting 1–3 weeks (symptoms are near continuous in 30%). 50% give no clear family history.

Features include:

• Fever >95%.
• Arthralgia and myalgia in 80%, often with centripetal migration.
• Abdominal pain in 80%.
• Rash in 70%: erythematous, oedematous plaques, discrete reticulate or serpiginous lesions that on biopsy contains superficial and deep perivascular infiltrates of mononuclear cells.
• Headache, pleuritic pain, lymphadenopathy, conjunctivitis and periorbital oedema.
• Symptoms are accompanied by a marked acute phase response.

Diagnosis:-

• By genetic testing.
• Levels of acute-phase reactants (CRP, sedimentation rate, and SAA) are increased during flares, and most patients exhibit leukocytosis and thrombocytosis during a flare.
• Acute-phase reactants may remain elevated in between clinical attacks,suggesting an elevated level of baseline inflammatory activity.

TREATMENT:-

• Colchicine is not effective in TRAPS.
• For relatively mild disease, NSAIDS agents may suffice.
•  For more severe disease with infrequent attacks, corticosteroids at the time of an attack may be effective, but it is not unusual for steroid requirements to increase over time.
• Etanercept is often effective in reducing the severity and frequency of flares, but longitudinal follow-up of TRAPS patients treated with etanercept indicates waning efficacy with time.
• Treatment of TRAPS with anti-TNF monoclonal antibodies has sometimes  led to a paradoxical worsening of disease.
• Experience with both anakinra, a recombinant IL-1 receptor antagonist, and canakinumab, a monoclonal anti–IL-1β antibody, has been favorable in TRAPS patients.

PROGNOSIS:-

• Without treatment >25% develop AA amyloidosis.
• Patients have poor growth, interrupted schooling and poor fertility.
• Life-long treatment is needed, but there is a good long-term outlook.

 Ibrahim Samaha

References:-

• Amanda K. Ombrello and Daniel L. Kastner , Hereditary Periodic Fever Syndromes and Other Systemic Autoinflammatory Diseases,Chapter 163,NELSON TEXTBOOK OF PEDIATRICS, TWENTIETH EDITION 2016
• Clarissa Pilkington, Kiran Nistala, Helen Lachman and Paul Brogan, Rheumatology , GREAT ORMOND STREET HANDBOOK OF PAEDIATRICS, 2nd  ed
• Osama Naga,Rheumatologic Disorders, Periodic Fever ,190-192 Pediatric Board Study Guide, A Last Minute Review
• Sujata Sawhney and Amita Aggarwal, Autoinflammatory Syndromes in Children, Pediatric Rheumatology,546-554 A Clinical Viewpoint,2017
• Ronald M. Laxer ,David D. Sherry  and Philip J. Hashkes,CH10 Autoinflammatory Syndromes,189-208 Pediatric Rheumatology in Clinical Practice,2nd ed 2016