Adult-onset tumour necrosis factor receptor-associated periodic syndrome presenting as transfusion-dependent refractory haemophagocytosis

A rare missense p.C125Y mutation in the TNFRSF1A gene identified in a Chinese family with tumor necrosis factor receptor-associated periodic fever syndrome

Background

Tumor necrosis factor receptor-associated periodic syndrome (TRAPS) is a rare autosomal dominant disorder with a low incidence in Asia. The most frequent clinical manifestations include fever, rash, myalgia, joint pain and abdominal pain. Misdiagnosis rates are high because of the clinical and genetic variability of the disease. The pathogenesis of TRAPS is complex and yet to be fully defined. Early genetic diagnosis is the key to precise treatment.

Methods

In this study, a Chinese family with suspected TRAPS were analyzed by genome-wide SNP genotyping, linkage analysis and targeted sequencing for identification of mutations in causative genes. To study the pathogenicity of the identified gene mutation, we performed a conservation analysis of the mutation site and protein structure analysis. Flow cytometry was used to detect TNFRSF1A shedding and quantitative real-time PCR were used to assess the activation of unfolded protein response (UPR) in the mutation carriers and healthy individuals.

Results

A typical TRAPS family history, with a pattern of autosomal dominant inheritance, led to the identification of a rare mutation in the TNFRSF1A gene (c.G374A [p.Cys125Tyr]) with unknown significance. The patient responded well to corticosteroids, and long-term therapy with colchicine effectively reduced the inflammatory attacks. No amyloid complications occurred during the 6-year follow-up. In silico protein analysis showed that the mutation site is highly conversed and the mutation prevents the formation of intrachain disulfide bonds in the protein. Despite a normal shedding of the TNFRSF1A protein from stimulated monocytes in the TRAPS patients with p.C125Y mutation, the expression of CHOP and the splicing of XBP1 was significantly higher than healthy controls, suggesting the presence of an activation UPR.

Conclusion

This is the first report of a Chinese family with the rare p.C125Y mutation in TNFRSF1A. The p.C125Y mutation does not result in aberrant receptor shedding, but instead is associated with an activated UPR in these TRAPS patients, which may provide new insights into the pathogenesis of this rare mutation in TRAPS.

Immunomodulatory Drugs in the Management of SARS-CoV-2

With the onset of the global pandemic in 2020 of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), there has been increasing research activity around certain disease-modifying drugs that are used for the management of inflammatory disorders such as rheumatoid arthritis, spondyloarthrosis, psoriatic arthritis, systemic lupus erythematosus, and inflammatory bowel disease for managing coronavirus symptoms. In the conditions mentioned, many people are on long-term treatment with agents including hydroxychloroquine, tumor necrosis factor alpha (TNFα) inhibitor drugs, other biologic agents such as monoclonal antibodies to IL-6 and Janus kinase inhibitors including baricitinib and tofacitinib, which are used to control inflammatory responses in their respective auto-immune condition. There is emerging data that immunomodulatory drugs could be protective at reducing certain features of SARS-CoV-2 and improving recovery. In addition, it is important to understand if subjects being treated with the immunomodulatory agents described have a less severe SARS-CoV-2 infection, as they are deemed some protection from their immunomodulatory treatment, or if they develop infections similar to non-immunocompromised patients. There is a huge unmet clinical need to advise patients responsibly about whether they should remain on their immunomodulatory treatment or not in light of Covid-19 infection. In this article we will discuss potential treatment options for SARS-CoV-2 using immunomodulatory drugs and at what stage of the condition they may be beneficial. Viable treatment options during the global coronavirus pandemic are a much-needed and an intensely active area of research.

Clinical and genetic features of Chinese adult patients with tumour necrosis factor receptor-associated periodic fever syndrome

Objectives

TNF receptor-associated periodic fever syndrome (TRAPS) is an autosomal dominant systemic autoinflammatory disease caused by mutations of TNF receptor superfamily member 1 A (TNFRSF1A) gene. TRAPS has hardly been reported in the Chinese population. We aimed to characterize the clinical and genetic features of Chinese adult patients with TRAPS.

Methods

Nine adult patients (≥16 years) were diagnosed during April 2015 to June 2019, at the Department of Rheumatology, Peking Union Medical College Hospital. Clinical and genetic features of these patients were evaluated and compared with those from Japan and Europe.

Results

The median age of disease onset was 3 (0.5–38.5) years old, and adult-onset was observed in two (22.2%) patients. The median time of diagnosis delay was 16.5 (1.5–50.5) years. One patient had a family history of TRAPS. The frequent symptoms were fever (nine, 100%), rash (seven, 77.8%), arthralgia/arthritis (five, 55.6%) and abdominal pain (five, 55.6%). Only two (22.2%) patients had periorbital oedema. Nine TNFRSF1A gene variants were detected, including C58R, G65E, F89L, C99G, V202G, V202D, c.769-23T>C, S290I and c.*64T>C. Rash was more frequently seen in Chinese than in Japanese and European patients, while chest pain and amyloidosis occurred less frequently.

Conclusion

This is the first and largest case series of TRAPS in Chinese adult patients. Two novel TNFRSF1A variants, S290I and V202G, have been identified. The different clinical manifestations of our patients compared with those from Japan and Europe might be related to their TNFRSF1A variants.