Periodic fever syndromes are autoinflammatory diseases. The majority present in infancy or childhood and are characterised by recurrent episodes of fever and systemic inflammation that occur in the absence of autoantibody production or identifiable infection. The best recognised disorders include CAPS, FMF, TRAPS and MKD. Understanding the molecular pathogenesis of these disorders provides unique insights into the regulation of innate immunity. Diagnosis relies on clinical acumen and is supported by genetic testing. With the exception of FMF, which is prevalent in populations originating from the Mediterranean, these syndromes are rare and easily overlooked in the investigation of recurrent fevers. Disease severity varies from mild to life threatening, and one of the most feared complications is AA amyloidosis. Effective therapies are available for many of the syndromes, including colchicine, IL-1 blockade and anti-TNF therapies, and there is an increasing interest in blocking interferon pathways.

Tumour necrosis receptor associated periodic syndrome (TRAPS) is a rare cosmopolitan dominant autosomal disease that belongs to the group of recurrent autoinflammatory syndromes. TRAPS is characterized by recurrent bouts of fever lasting more than 7 days, with arthralgia, myalgia, abdominal pain, erythematous rash and sometimes ocular symptoms. During flares, raised inflammatory markers are constant. The age of onset may occur during childhood but also during adulthood. TRAPS is caused by mutations in the TNF receptor 1 (TNFRSF1A) gene that may occur in most of the populations over the world. In the majority of patients, history shows affected relatives, even if sporadic cases do exist. Management of TRAPS usually involves corticosteroid therapy during inflammatory flares. The most severe cases require a treatment with biological agents (mainly interleukin 1 inhibitors). The prognosis of TRAPS is overall good; the main risk is represented by the development of secondary inflammatory amyloidosis. This risk is greatest in patients with structural mutations leading to conformation abnormalities of the TNFRSF1A receptor. Regular clinical and biological monitoring is essential in the follow-up of TRAPS patients.

Tumor necrosis factor receptor-associated periodic syndrome (TRAPS) is characterized by recurrent episodes of inflammation with fever, abdominal pain, chest pain, rash, myalgia, arthralgia, conjunctivitis, and periorbital edema. This condition is a rare autosomal dominant disease that is strongly associated with heterozygous mutations in the tumor necrosis factor (TNF) receptor super family 1A (TNFRSF1A) gene. This condition is believed to be more common in Western countries than in Asian countries, and the AA amyloidosis rate for European countries is estimated to be 10%. Herein, we report the case of a 14-year-old girl with recurrent fever and arthralgia with inflammatory marker elevation for 10 years. After extensive investigation of the infectious etiology with negative results and similar phenomenon observed within her family, the diagnosis of TRAPS was made based on next-generation sequencing, which revealed a T50M mutation; she was also sensitive to corticosteroids. Although none of our TRAPS patients developed AA amyloidosis, we suggest the continual monitoring of urinalysis results and serum amyloid A concentrations during long-term follow-up. Moreover, we also reviewed the related literature and found no Asian patients who had developed AA amyloidosis.

Tumor necrosis factor-associated periodic syndrome is an autoinflammatory disorder classified under hereditary periodic fever syndromes. Mutations in the tumor necrosis factor receptor contribute to tumor necrosis factor-associated periodic syndrome. Decreased shedding of receptors and increased mitochondrial reactive oxygen species production leading to elevated proinflammatory cytokines are documented. Inflammation in various organs is hallmark of tumor necrosis factor-associated periodic syndrome and manifests as spiking fever, abdominal pain, conjunctivitis and polyserositis in adults. The ongoing challenge is to diagnose the disease early in its course to prevent amyloidosis. The treatment options have evolved from use of nonsteroidal anti-inflammatory drugs and corticosteroids to targeted therapy like tumor necrosis factor receptor inhibitors and interleukin-1 blockers. The aim of this review is to give an overview of the pathogenesis, clinical features and the various treatment modalities available for tumor necrosis factor-associated periodic syndrome and aid physicians in recognizing the signs of the disease earlier.

TNF receptor associated periodic syndrome (TRAPS) is an autoinflammatory disease caused by mutations in TNF Receptor 1 (TNFR1). Current therapies for TRAPS are limited and do not target the pro-inflammatory signalling pathways that are central to the disease mechanism. Our aim was to identify drugs for repurposing as anti-inflammatories based on their ability to down-regulate molecules associated with inflammatory signalling pathways that are activated in TRAPS. This was achieved using rigorously optimized, high through-put cell culture and reverse phase protein microarray systems to screen compounds for their effects on the TRAPS-associated inflammatory signalome. 1360 approved, publically available, pharmacologically active substances were investigated for their effects on 40 signalling molecules associated with pro-inflammatory signalling pathways that are constitutively upregulated in TRAPS. The drugs were screened at four 10-fold concentrations on cell lines expressing both wild-type (WT) TNFR1 and TRAPS-associated C33Y mutant TNFR1, or WT TNFR1 alone; signalling molecule levels were then determined in cell lysates by the reverse-phase protein microarray. A novel mathematical methodology was developed to rank the compounds for their ability to reduce the expression of signalling molecules in the C33Y-TNFR1 transfectants towards the level seen in the WT-TNFR1 transfectants. Seven high-ranking drugs were selected and tested by RPPA for effects on the same 40 signalling molecules in lysates of peripheral blood mononuclear cells (PBMCs) from C33Y-TRAPS patients compared to PBMCs from normal controls. The fluoroquinolone antibiotic lomefloxacin, as well as others from this class of compounds, showed the most significant effects on multiple pro-inflammatory signalling pathways that are constitutively activated in TRAPS; lomefloxacin dose-dependently significantly reduced expression of 7/40 signalling molecules across the Jak/Stat, MAPK, NF-κB and PI3K/AKT pathways. This study demonstrates the power of signalome screening for identifying candidates for drug repurposing.

One purpose of this review was to raise awareness for the new autoinflammatory syndromes. These diseases are increasingly recognized and are in the differential diagnosis of many disease states. We also aimed to review the latest recommendations for the diagnosis, management, and treatment of these patients.

Tumor necrosis factor receptor-associated periodic syndrome (TRAPS), caused by mutations in the TNFRSF1A gene, is the most frequent autosomal dominant autonflammatory disease displaying a relevant risk of reactive AA amyloidosis, if left untreated. Our report deals with one adult with TRAPS complicated by amyloidosis-related renal failure, treated with the recombinant human interleukin-1 receptor antagonist anakinra at a higher than conventional dosage. This treatment did not present any adverse event and led remarkably to the disappearance of all TRAPS-related manifestations and prompt decrease of laboratory abnormalities, including proteinuria. A review of the medical literature has been also considered to evaluate efficacy and safety of interleukin-1 inhibition in patients with TRAPS.

Autoinflammatory diseases are disorders of the innate immune system characterized by uncontrolled inflammation. The most commonly encountered autoinflammatory diseases are the hereditary periodic fever syndromes, which present with fever and other features of the skin, serosal membranes, and musculoskeletal system. The main inherited (monogenic) periodic fever syndromes are familial Mediterranean fever (FMF), cryopyrin-associated periodic syndrome (CAPS), tumor necrosis factor receptor-associated periodic syndrome (TRAPS), and hyperimmunoglobulin D syndrome (HIDS)/mevalonate kinase deficiency (MKD). Recent advances in our understanding of the molecular and pathophysiological basis of autoinflammatory diseases have provided new treatment strategies. Patients with periodic fever syndromes have clearly benefited from anti-interleukin (IL)-1 treatment. Colchicine is still the mainstay of FMF therapy, but IL-1 blockade is also effective if colchicine fails. Early diagnosis and effective treatment can prevent irreversible organ damage. The scope of pathogenic mutations and more targeted therapy for better management of these rare diseases remains to be defined.