Glossary – L,M,N,O,P

Macrophage Activation Syndrome (MAS)

A rare, potentially life-threatening disorder characterized by overactive and abnormal response from the immune system. It can develop in people with autoinflammatory conditions like Still’s disease. MAS can lead to organ damage and should be treated aggressively by your doctor. Tell your doctor right away if your AOSD or SJIA symptoms get worse or if you have any of these symptoms of an infection, such as a fever lasting longer than 3 days, a cough that does not go away, redness in one part of your body, or a warm feeling or swelling of your skin.

Majeed syndrome

A rare, recessive, autoinflammatory disorder caused by inheriting two mutated copies of the LPIN2 gene, causing bone pain, fever, anaemia and in some cases, skin lesions.

Muckle-Wells Syndrome (MWS)

A rare autoinflammatory disease considered moderate in a group called cryopyrin-associated periodic syndromes (CAPS), characterised by rash, fever, joint pain and hearing loss.

Neutrophil-lymphocyte ratio (NLR)

Ratio of neutrophils to lymphocytes, which are both types of white blood cells. An elevated NLR can indicate inflammation.

Neonatal Onset Multisystem Inflammatory Disease (NOMID) known in some countries as Chronic Infantile Neurological Cutaneous Articular Syndrome (CINCA)

A rare autoinflammatory disease considered severe in a group called cryopyrin-associated periodic syndromes (CAPS), characterised by chronic inflammation affecting the central nervous system, skin rash and bony overgrowth in joints, especially knees, often leading to significant morbidity if untreated.

Nonsteroidal anti-inflammatory drugs (NSAIDs)

Medications, like ibuprofen, used to relieve pain and reduce inflammation.

Paediatric Rheumatologist

A doctor who specialises in treating children and adolescents with rheumatic diseases, including arthritis, many autoimmune diseases, and many autoinflammatory diseases.

Procalcitonin (PCT)

A precursor to the hormone calcitonin, elevated levels can indicate bacterial infection and systemic inflammation.

Periodic Fever Syndromes (PFS)

A group of rare, autoinflammatory diseases that are characterised by symptoms including recurrent fevers, rash, pain, and joint inflammation.

Periodic Fever, Aphthous Stomatitis, Pharyngitis, and Adenitis (PFAPA) syndrome

A condition characterised by recurrent episodes of fever, mouth sores, sore throat, and swollen lymph nodes.

Plasma viscosity (PV)

A measure of blood plasma thickness, elevated levels can be a marker of inflammation.

Pyoderma gangrenosum, acne, suppurative hidradenitis (PASH)

Same as PAPA without the pyogenic arthritis.

Pyogenic Arthritis, Pyoderma Gangrenosum and Acne (PAPA) syndrome

A rare autoinflammatory disease causing skin lesions and joint pain.