• Acute attack: Sudden, severe clinical episode of short duration
  • Acute gout attacks: A sudden, severe episode of pain of short duration associated with gout
  • Amyloidosis: Protein deposits that result from inflammation and can damage tissues and organs
  • Antibodies: Protein molecules formed by the immune system to fight pathogens. Antibodies are similar in structure to each other but are unique in the parts that recognizes germs.
  • Arthralgia: Pain in a joint
  • Arthritis: Joint inflammation
  • Articular: Related to the joints in your body
  • Autoimmune, autoimmune diseases: Diseases where the acquired immune system turns against the body’s own tissues
  • Autoinflammatory: Related to inflammation in the body that is not due to infections or injuries


  • Bacteria: Single-cell organisms (microorganisms); a kind of germ


  • CAPS: Cryopyrin-associated periodic syndrome, a rare periodic fever syndrome consisting of three sub-forms of different severity
  • Chronic: Permanently existing or recurrent symptoms. Slowly developing, insidious, long-lasting.
  • CINCA: Chronic infantile neurological, cutaneous and articular syndrome, one of the CAPS diseases; another name for NOMID, the most severe form of CAPS
  • Comorbidity: Accompanying disease
  • Conjunctivitis: Inflammation of the eye’s conjunctiva
  • CRP: The C-reactive protein, abbreviated CRP, is a plasma protein that is produced in the liver and belongs to the acute-phase proteins. A protein that indicates an inflammation in the body.
  • Cutaneous: Relating to the skin
  • Cytokine: Messenger substance in the immune system
  • Cytopenia: Too few cells of a particular type


  • Diagnosis: Identification of a disease by a physician
  • Differential diagnosis: All diagnoses that can serve as an explanation for the symptoms are collected and checked to see if they apply
  • DNA: Deoxyribonucleic acid (DNA) is the name given to the chemical structure of the genetic information that forms the blueprint for our bodies


  • Enthesitis: Tendinitis
  • Enzyme: A molecule, such as a protein that accelerates the break-down or building of substances


  • FCAS: Familial cold-induced auto-inflammatory syndrome; is one of the CAPS diseases
  • Fever of unknown origin (FUO): This means fever (>38°C) on different days and lasting longer than three weeks with an unclear diagnosis despite appropriate tests during at least three outpatient visits or three days in the hospital
  • Fever syndrome: Characterized mostly by recurrent bouts of fever that are accompanied by other manifestations, e.g. on the skin, mucous membranes, serous membranes and joints
  • Flare: A sudden eruption of symptoms
  • FMF: Familial Mediterranean fever


  • Gene: A segment of DNA that codes for a protein. If a disease is passed on through genes, it means that it can be inherited from family members/relatives. Traits, such as brown hair are also passed on this way. If both parents have brown hair, it is likely that their child will also have brown hair. The same applies to CAPS: If a parent suffers from CAPS, it is quite possible that the child will develop CAPS.
  • Gout attack: Small raised bumps (nodules) associated with gout
  • Gout: Metabolic disease where too much uric acid is accumulated in the blood, resulting in the formation of uric acid deposits
  • Gouty arthritis: A manifestation of gout in the joints


  • Hereditary periodic fever syndromes: Also called auto-inflammatory syndrome; characterized mostly by recurrent bouts of fever that are accompanied by other manifestations, e.g. on the skin, mucous membranes and joints
  • Hereditary: Passed on from parents to children
  • HIDS: Hyper-IgD syndrome
  • HPF: Hereditary periodic fever syndromes
  • Hyperuricemia: An increase in the uric acid level in the blood


  • Idiopathic: Unclear origin
  • IgD: Immunoglobulin D, antibodies of class D
  • IL-18: Interleukin 18, an important messenger substance of the immune system
  • IL-1ß: Interleukin 1ß, an important messenger substance of the immune system
  • IL-6: Interleukin-6, an important messenger substance of the immune system
  • Immune system: Defense system of the body against diseases
  • Incidence: Number of new cases of a specific disease within a given population within a specified time
  • Infantile: Relating to children in infancy (usually until the age of about one year)
  • Infection: Inflammation due to microorganisms
  • Inflammation: The body’s own natural defenses to protect against infection or injuries. People with autoinflammation suffer from symptoms associated with inflammation that are not due to infection or injuries. Inflammation may include local redness, swelling, and increased temperature that is associated with infection or injury
  • Inflammatory disease: A disease caused by inflammation. CAPS is a special type of inflammatory disease called auto-inflammatory disease. See also the definition for “auto-inflammatory”.
  • Interleukin: The body’s own messenger substances of immune system cells
  • Intermittent: In between, interrupting


  • JIA: Juvenile idiopathic arthritis, a common rheumatoid disease in childhood
  • Juvenile: In childhood


  • Kidney damage: Impaired kidney functioning due to pathological kidney changes; among other things, leads to increase of substances in the blood that are normally excreted in the urine and now become toxic in the body
  • Kidney stones: Deposits in the urinary tract (kidneys, ureters, bladder) that consist of the breakdown product uric acid. They can lead to urinary stones


  • Leukocytosis: Leukocytosis refers to an increase in the number of white blood cells (leukocytes) in the blood


  • Macrophage: A type of cell of the immune system that is responsible for engulfing and digesting invading germs
  • MAS: Macrophage activation syndrome, a dangerous, sepsis-like complication in SJIA
  • MEFV gene: Gene whose change (mutation) is responsible for the occurrence of Mediterranean fever
  • MNU crystals: Uric acid salt crystals
  • Monoarthritis: Arthritis that occurs only in one joint
  • Monocyclic: One time
  • Monocyte: Cell of the immune system
  • Mutation: Changes in genes
  • MVK: Mevalonate kinase
  • MWS: Muckle-Wells syndrome, one of the CAPS disorders
  • Myalgia: Pain in a muscle


  • Neonatal: Relating to the newborn
  • Nephropathy: The medical term for diseases of the kidney or of kidney function
  • Neurologic: Relating to the brain, spinal cord and nervous system of the body
  • Nicotinic acid: Also: niacin, a vitamin from the B complex
  • NOMID: Most severe form of CAPS, another name for it is CINCA


  • Oligoarthritis: Arthritis in fewer than five joints
  • Osteoporosis: Bone disease that leaves the bone prone to fractures, also called “bone loss”


  • Pathogens: Disease causing organisms
  • Periodic: Occurring at regular intervals
  • Persistent: Continuing
  • Phagocytes: Cells responsible for engulfing and digesting invading pathogens
  • Polyarthritis: Arthritis in many joints
  • Polycyclic: Constantly recurrent
  • Prevalence: Number of people with a disease at a given time
  • Protein deposits: Proteins are the building blocks that are needed throughout the body. They are an important part of cells responsible for the body’s own defense. Usually there are hardly any protein deposits in the kidney. Heavy protein deposits in the kidney may be a sign of an infection and should be promptly treated by a doctor.
  • Proteins: Folded strings of amino acids that form the building blocks of cells


  • Relapsing: Recurrent
  • Rheumatism: Collective term for various joint diseases


  • SAA: Serum amyloid A, a protein substance that can be formed during inflammation in the liver and can then be detected in the blood. High SAA levels in the blood are a cause of amyloidosis.
  • Sepsis: Colloquially also “blood poisoning”
  • Serositis: Term for an inflammation of the lining of the lungs, heart or abdomen and abdominal organs
  • Serum: The portion of the blood from which blood cells and fibrin (= clotting factor) have been removed and which can no longer clot
  • SJIA: Systemic form of juvenile idiopathic arthritis
  • Still’s disease/syndrome: Another name for SJIA
  • Streptococci: Type of bacteria
  • Symptoms: Complaints that occur with a particular disease
  • Syndrome: Simultaneous presence of various symptoms that are typical for a particular disease


  • Thrombosis: The blood coagulates and forms clots that clog the blood vessel
  • TNF: Tumour necrosis factor
  • TNFR: Tumour necrosis factor receptor superfamily, member 1A
  • Tophi: Small raised bumps (nodules) associated with gout
  • TRAPS: TNF-receptor-associated periodic syndrome


  • Urates: The salts of uric acid are called urates
  • Uric acid: The end product of protein metabolism in people. The kidneys excrete uric acid from the body in urine; increased uric acid in the blood (hyperuricemia) may lead to gout
  • Urticaria: Inflammatory rash

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