Autoinflammatory syndromes (AIS) are a group of related inflammatory disorders. In fact, they are characterized by unprovoked repeated episodes of systemic inflammations that usually go with fever, rash and serositis. Most importantly, AIS are connected based on several characteristics:
1- Innate immunity dysregulation
2- Activation of inflammasome
3- Clinical features such as fever, neutrophilic rashes, and bone or synovial problems
4- Acute phase responses
5- Positive results after cytokine inhibitors treatment
WHAT CAUSES AIS?
These disorders are caused by genetic mutations at the level of the innate immune system sensors. As a matter of fact, these sensors are known as pathogen-recognition receptors (PRR) and they include Toll-like receptors (TLRs), RIG-I like receptors (RLRs), NOD-like receptors (NLRs), and DNA receptors (cytosolic receptors for DNA).
ARE AUTOINFLAMMATORY SYNDROMES THE SAME AS AUTOIMMUNITY?
Autoimmunity and are not the same. Unlike autoimmunity, AIS is a disease that is not concerned with antibodies, T-cell mediated pathways, or major histocompatibility-complex related processes.
LIST OF AUTOINFLAMMATORY SYNDROMES:
1- Tumor necrosis factor receptor-associated periodic syndrome (TRAPS) or Familial Hibernian Fever
2- Familial Mediterranean Fever (FMF)
3- Hyperimmunoglobulin D syndrome (HIDS)
4- Cryopyrin-associated periodic syndrome (CAPS):
- Familial cold autoinflammatory syndrome (FCAS)
- Muckle wells syndrome (MWS)
- Chronic infantile neurologic cutaneous articular syndrome OR Neonatal-onset multisystem inflammatory disease (CINCA/NOMID)
-Still’s disease
-Schnitzler syndrome
5- Pyogenic Arthritis, Pyoderma gangrenosum and Acne (PAPA):
- Blau Syndrome
- DIRA and DITRA
- Chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature syndrome (CANDLE)
- Majeed syndrome
6- Periodic fever, aphthous somatitis, pharyngitis, and adenopathy (PFAPA)
References:
-Zeft AS, Spalding SJ. Autoinflammatory syndromes: fever is not always a sign of infection. Cleve Clin J Med. 2012 Aug;79(8):569-81. doi: 10.3949/ccjm.79a.11184. PMID: 22854436.
-Cush JJ. Autoinflammatory syndromes. Dermatol Clin. 2013 Jul;31(3):471-80. doi: 10.1016/j.det.2013.05.001. PMID: 23827249; PMCID: PMC4489412.
- Verbsky JW. When to Suspect Autoinflammatory/Recurrent Fever Syndromes. Pediatr Clin North Am. 2017 Feb;64(1):111-125. doi: 10.1016/j.pcl.2016.08.008. PMID: 27894439.
- Kumar H, Kawai T, Akira S. Pathogen recognition by the innate immune system. Int Rev Immunol. 2011 Feb;30(1):16-34. doi: 10.3109/08830185.2010.529976. PMID: 21235323.
- Vineetha M, Palakkal S, Skaria L, Jose N, Philomina D, Nithin A. Autoinflammatory syndromes: A review. J Skin Sex Transm Dis 2020;2(1):5-12.
