TNF receptor-associated periodic syndrome (TRAPS)

What happens in this disease?

A change in the TNFRSF1A gene causes a protein called TNF receptor 1 to fold incorrectly. This protein builds up inside the cell and constantly stimulates inflammation. As a result, attacks of fever and inflammation happen without any germs. Attacks usually last 1 to 3 weeks.

Which symptoms can occur?

The first attack usually happens in childhood. Symptoms may include:

• Repeated, long-lasting fever (common)
• Muscle pain spreading to the arms and legs
• A red, painful rash that spreads
• Abdominal pain, nausea and vomiting
• Swelling around the eyes or eye inflammation
• Joint and chest pain
• Build-up of a protein called amyloid in the kidneys (sometimes)

How is it diagnosed?

The doctor suspects TRAPS based on the symptoms and family history. During attacks, inflammation markers rise in the blood. The diagnosis is confirmed with a genetic test of the TNFRSF1A gene. The urine is also checked for protein.

Treatment and care

Anti-inflammatory medicines and cortisone can be used to ease attacks. Biological medicines that block a substance called IL-1, which starts inflammation, can clearly reduce attacks. There is an approved biological treatment for this disease. People on treatment need regular blood and urine tests. The doctor who follows the disease decides which treatment is suitable.

For the family: inheritance and genetic counselling

Inheritance is dominant. For each child of an affected parent, the chance is 1 in 2. Not everyone who carries the gene may become ill. Sometimes the gene change is new. Genetic counselling is recommended for family members with similar complaints.