Neurological manifestations of autoinflammatory diseases in Chinese adult patients

Yao Syndrome: An Overview of Genotypic Associations, Clinical Manifestations, Diagnosis, and Treatment

BACKGROUND

Yao syndrome (YAOS) is a rare systemic autoinflammatory disorder (AID) of the innate immune system. It was recently categorized as genetically transitional disease (GTD) and is associated with NOD2 variants located at multiple NOD2 gene loci. Unlike most other periodic fever syndromes, the estimated disease prevalence is 1-10/100,000 with a predominance for females and white adult population. In this review, we aimed to provide a detailed analysis of different aspects of this syndrome to help better understand the underlying pathogenesis and incorporate the current evidence-based medicine published to diagnose and manage these patients.

SUMMARY

We conducted literature search on YAOS from 2011 to 2024 using PubMed, Embase, and Scopus databases. Thirty-two studies were included in our narrative review. A descriptive analysis was performed of both Yao and non-Yao authored records to embrace the syndrome reported from all investigators and assess differences and similarities. The most reported gene variant is the homozygous IVS8+158 followed by compound heterozygous IVS8+158 and R702W. Mean age of disease onset is between 36 and 42 years. The mean age of disease diagnosis is between 40 and 45 years with a variable disease duration. Fever is the most commonly reported symptom followed by musculoskeletal, gastrointestinal symptoms and dermatitis. On laboratory workup, patients have elevated levels of erythrocyte sedimentation rate, C-reactive protein, and serum ferritin with negative autoantibody workup. Arthritic symptoms in YAOS patients have a positive response to sulfasalazine and glucocorticoids, while nonsteroidal anti-inflammatory drugs and colchicine produce minimal response. Anti-IL1 and anti-IL6 agents (canakinumab, anakinra, and tocilizumab) are effective treatment modalities.

KEY MESSAGES

The evolving concept and acceptance of GTD will hopefully further our understanding about this SAID and similar disorders. We suggest developing a registry of patients with YAOS to keep track of expanding data on this subject. It is important to understand various aspects of YAOS including genetic and environmental factors, differential diagnosis, clinical manifestations, laboratory findings, and treatment options available to diagnose and manage these patients appropriately and timely.

Expanding clinical characteristics and genotypic profiling of Yao syndrome in Chinese patients

Objectives

Yao syndrome (YAOS, OMIM# 617321) is a kind of systemic autoinflammatory diseases (SAIDs) linked to the nucleotide-binding oligomerization domain containing 2 (NOD2). Clinical reports of YAOS in China are sparse. Herein, we reported the largest YAOS cohort of Chinese patients to expand the understanding of its phenotype, genotype, and therapeutic responses.

Methods

This study enrolled 15 adult patients diagnosed with YAOS at Peking Union Medical College Hospital from April 2015 to May 2024. Whole-exome sequencing was performed on all patients. Clinical data, genetic variations, and treatment responses were documented and compared with a Caucasian cohort.

Results

The mean age of disease onset was 35 ± 17 years old. The most common clinical manifestations included recurrent high-grade fever (100%), gastrointestinal symptoms (73.3%), arthralgia/arthritis, fatigue, myalgia, and lower extremity swelling (46.7%). All patients exhibited elevated acute-phase reactants during episodes. 12 heterozygous NOD2 variants were identified, with Q902K in 4 patients, R471C in 3, and variants c.-14C>T, A110T, S127L, R311W, A432V, Y514H, R541P, A661P, K818Q, A886V each found in individual patients. 90% of the patients responded well to glucocorticoids, and 55.6% to sulfasalazine. 66.7% of patients who received TNF inhibitors achieved complete resolution of symptoms. Additionally, one patient each responded favorably to canakinumab and tocilizumab. Compared to the Caucasian cohort, our cohort exhibited a more balanced gender ratio and a higher proportion of recurrent fever, proteinuria/hematuria as well as more frequent leukocytosis, elevated acute phase reactants, and anemia. Lower proportions of arthralgia/arthritis, skin rashes, headaches, and sicca-like symptoms were noted in our cohort. Moreover, a higher proportion of patients in our cohort showed a good response to TNF inhibitors.

Conclusion

Chinese patients with YAOS had more pronounced inflammatory manifestations compared to the Caucasian cohort. Variants c.-14C>T, A110T, S127L, A661P, K818Q, A886V, R471C, and A432V were identified as novel NOD2 variants in YAOS. TNF, IL-6, and IL-1 inhibitors are the promising treatment options. These findings expand the clinical spectrum, genetic profile, and treatment efficacy of YAOS, underscoring the need for heightened awareness of this disease in diverse populations.

Identifying high-risk neurological phenotypes in adult-onset classic monogenic autoinflammatory diseases: when should neurologists consider testing?

BACKGROUND

Monogenic autoinflammatory disorders result in a diverse range of neurological symptoms in adults, often leading to diagnostic delays. Despite the significance of early detection for effective treatment, the neurological manifestations of these disorders remain inadequately recognized.

METHODS

We conducted a systematic review searching Pubmed, Embase and Scopus for case reports and case series related to neurological manifestations in adult-onset monogenic autoinflammatory diseases. Selection criteria focused on the four most relevant adult-onset autoinflammatory diseases-deficiency of deaminase 2 (DADA2), tumor necrosis factor receptor associated periodic fever syndrome (TRAPS), cryopyrin associated periodic fever syndrome (CAPS), and familial mediterranean fever (FMF). We extracted clinical, laboratory and radiological features to propose the most common neurological phenotypes.

RESULTS

From 276 records, 28 articles were included. The median patient age was 38, with neurological symptoms appearing after a median disease duration of 5 years. Headaches, cranial nerve dysfunction, seizures, and focal neurological deficits were prevalent. Predominant phenotypes included stroke for DADA2 patients, demyelinating lesions and meningitis for FMF, and meningitis for CAPS. TRAPS had insufficient data for adequate phenotype characterization.

CONCLUSION

Neurologists should be proactive in diagnosing monogenic autoinflammatory diseases in young adults showcasing clinical and laboratory indications of inflammation, especially when symptoms align with recurrent or chronic meningitis, small vessel disease strokes, and demyelinating lesions.

A novel Nlrp3 knock-in mouse model with hyperactive inflammasome in development of lethal inflammation

NOD-like receptor family, pyrin domain-containing 3 (NLRP3) is a central protein contributing to human inflammatory disorders, including cryopyrin-associated periodic syndrome and sepsis. However, the molecular mechanisms and functions of NLRP3 activation in various diseases remain unknown. Here, we generated gain-of-function knock-in mice associated with Muckle-Wells syndromes using the Cre-LoxP system allowing for the constitutive T346M mutation of NLRP3 to be globally expressed in all cells under the control of tamoxifen. The mice were treated with tamoxifen for 4 days before determining their genotype by PCR and sequence analysis. In vitro, we found that bone marrow-derived macrophage from homozygous T346M mutation mice displayed a robust ability to produce IL-1β in response to lipopolysaccharide exposure. Moreover, ASC specks and oligomerization were observed in the homozygous mutant bone marrow-derived macrophages in the presence of lipopolysaccharides alone. Mechanistically, K+ and Ca2+ depletion and mitochondrial depolarization contribute to the hyperactivation of mutant NLRP3. In vivo, homozygous mice carrying the T346M mutation exhibit weight loss and mild inflammation in the resting state. In the lipopolysaccharide-mediated sepsis model, homozygous mutant mice exhibited higher mortality and increased serum circulating cytokine levels, accompanied by serious liver injury. Furthermore, an increase in myeloid cells in the spleen has been suggested to be a risk factor for inducing sepsis sensitivity. Altogether, we describe a cryopyrin-associated syndrome animal model with the T346M mutation of NLRP3 and suggest that the hyperactivated inflammasome aggregated by the mutant NLRP3 lowers the inflammatory response threshold both in vitro and in vivo.

The expanding clinical spectrum of autoinflammatory diseases with NOD2 variants: a case series and literature review

Objective

To assess the impact conferred by NOD2 variants on the clinical spectrum of patients with systemic autoinflammatory diseases (SAIDs) in Greece.

Methods

Consecutive patients (n=167) with confirmed SAIDs who underwent screening by next generation sequencing (NGS) targeting 26 SAID-associated genes, and carried at least one NOD2 gene variant, were retrospectively studied. The demographic, clinical and laboratory parameters were recorded.

Results

In total, 24 rare NOD2 variants in 23/167 patients (14%) were detected. Notably, 18 patients had at least one co-existing variant in 13 genes other than NOD2. Nine patients had juvenile- and 14 adult-onset disease. All patients presented with symptoms potentially induced by the NOD2 variants. In particular, the candidate clinical diagnosis was Yao syndrome (YAOS) in 12 patients (7% of the whole SAID cohort). The clinical spectrum of patients with YAOS (mean episode duration 8 days) was fever (n=12/12), articular symptoms (n=8), gastrointestinal symptoms (n=7; abdominal pain/bloating in 7; diarrhea in 4; oral ulcers in 3), serositis (n=7), and rash (n=5), while the inflammatory markers were elevated in all but one patient. Most of these patients showed a poor response to nonsteroidal anti-inflammatory drugs (n=7/9), colchicine (n=6/8) and/or anti-TNF treatment (n=3/4), while a complete response was observed in 6/10 patients receiving steroids and 3/5 on anti-IL1 treatment. Another 8 patients were diagnosed with either FMF (n=6) or PFAPA syndrome (n=2) presenting with prominent diarrhea (n=7), oral ulcers (n=2), periorbital swelling and sicca-like symptoms (n=1), or maculopapular rash (n=1). One patient had a clinically undefined SAID, albeit characterized by oral ulcers and diarrhea. Finally, one patient presented with chronic relapsing urticaria with periorbital edema and inflammatory markers, and another one had a Crohn-like syndrome with good response to anti-IL-1 but refractory to anti-TNF treatment.

Conclusion

NOD2 variants were detected in 1 out of 7 SAID patients and seem to have an impact on disease phenotype and treatment response. Further studies should validate combined molecular and clinical data to better understand these distinct nosological entities.

The phenotype and genotype of Chinese adult patients with NLRP3-associated autoinflammatory disease

OBJECTIVES

NLRP3-associated autoinflammatory disease (NLRP3-AID) is a spectrum of autosomal dominant inherited diseases associated with NLRP3 gene mutations. Reports of Chinese NLRP3-AID cases are limited to date. In the present study, we aim to describe the phenotype and genotype of a cohort of Chinese adult NLRP3-AID patients METHODS: This single-center study included sixteen adult patients diagnosed with NLRP3-AID at Department of Rheumatology, Peking Union Medical College Hospital from April 2015 to September 2021. Whole-exome sequencing using next-generation sequencing was performed in each patient. Clinical data and mutational information were compared with a European cohort.

RESULTS

The median age of disease onset was 16 (0-46) years old, and adult-onset was observed in 4 patients (25%). The median time of diagnosis delay was 20 (0-39) years. Five patients (31.3%) had family history of similar symptoms. The most common clinical manifestations were recurrent fever (93.8%), arthralgia/arthritis (81.3%), skin rash (75%), myalgia (62.5%), and central nervous system manifestations (50%). Heterozygous NLRP3 variants detected in these patients were p.T348M (n = 4, 25%), Q703K, V70M, K129R, M116I, P38S, V442I, D303G, G326E, A439V, K829T, L632F and V198M (n = 1, separately). All the variants were missense mutations.

CONCLUSIONS

We reported the largest case series of Chinese adult NLRP3-AID patients. The distinct symptoms of NLRP3-AID patients suggest the heterogeneity of disease. P38S, M116I, K129R, V442I and K829T were identified as novel NLRP3 variants. These data expand the clinical phenotypic and genotypic profiles of NLRP3-AID. Key Points • We characterized the clinical and genetic features of sixteen Chinese adult NLRP3-AID patients. • Thirteen NLRP3 gene variants were confirmed in this cohort, and P38S, M116I, K129R, V442I and K829T were identified as novel variants. • Clinical data and mutation information were compared with a European cohort. • We hope these data would expand the phenotypic and genotypic profile of NLRP3-AID and raise the awareness of early diagnosis and accurate treatment among rheumatologists.

Familial Mediterranean Fever and multiple sclerosis treated with ocrelizumab: Case report

BACKGROUND

Familial Mediterranean Fever (FMF) is associated with increased risk of multiple sclerosis (MS). Optimal treatment of patients with comorbid FMF and MS remains uncertain.

CASE

A 28-year-old woman with FMF, treated with colchicine, had symptomatic onset of relapsing remitting MS following four simultaneous vaccines. MRI brain with a 7-Tesla magnet demonstrated several areas of leptomeningeal enhancement with predominant linear, spread/fill and rare nodular patterns. Central vein signs were present in supratentorial white matter lesions. She received four cycles of ocrelizumab and achieved no evidence of disease activity (NEDA-3) at 20 months' follow up.

DISCUSSION

FMF with incident CNS demyelinating disease demonstrated neuroimaging features typical for classic RRMS including the central vein sign and leptomeningeal enhancement. Treatment with B-cell depleting therapy for FMF-MS led to clinical stability and symptomatic improvement at 20 months' follow up. We add to the sparse literature characterizing the course of FMF as a genetic risk factor for CNS demyelinating disease, demonstrating pathognomonic imaging features of MS on 7 T imaging and treatment efficacy with B-cell depletion.

Neuroinflammation Associated With Inborn Errors of Immunity

The advent of high-throughput sequencing has facilitated genotype-phenotype correlations in congenital diseases. This has provided molecular diagnosis and benefited patient management but has also revealed substantial phenotypic heterogeneity. Although distinct neuroinflammatory diseases are scarce among the several thousands of established congenital diseases, elements of neuroinflammation are increasingly recognized in a substantial proportion of inborn errors of immunity, where it may even dominate the clinical picture at initial presentation. Although each disease entity is rare, they collectively can constitute a significant proportion of neuropediatric patients in tertiary care and may occasionally also explain adult neurology patients. We focus this review on the signs and symptoms of neuroinflammation that have been reported in association with established pathogenic variants in immune genes and suggest the following subdivision based on proposed underlying mechanisms: autoinflammatory disorders, tolerance defects, and immunodeficiency disorders. The large group of autoinflammatory disorders is further subdivided into IL-1β-mediated disorders, NF-κB dysregulation, type I interferonopathies, and hemophagocytic syndromes. We delineate emerging pathogenic themes underlying neuroinflammation in monogenic diseases and describe the breadth of the clinical spectrum to support decisions to screen for a genetic diagnosis and encourage further research on a neglected phenomenon.

Bilateral Optic Disc Swelling as a Plausible Common Ocular Sign of Autoinflammatory Diseases: Report of Three Patients with Blau Syndrome or Cryopyrin-Associated Periodic Syndrome

The aim of this study is to describe bilateral optic disc swelling in three consecutive patients with Blau syndrome or cryopyrin-associated periodic syndrome at a single institution. Case 1 was a 30-year-old woman receiving 25 mg etanercept twice weekly who had been diagnosed as early-onset sarcoidosis by biopsy of skin rashes at 5 months old and genetically diagnosed with Blau syndrome with CARD15/NOD2 mutation (N670K) at 13 years old. At 10 years old, she began to have uveitis with optic disc swelling in both eyes, resulting in macular degeneration and optic disc atrophy at 17 years old only when etanercept was introduced. Case 2 was a 21-year-old man receiving adalimumab every 2 weeks who had been diagnosed as early-onset sarcoidosis by biopsy of skin rashes at 1.5 years old and genetically diagnosed as Blau syndrome with CARD15/NOD2 mutation (C495Y) at 5 years old. At 8 years old, around the time of adalimumab introduction, he began to show bilateral optic disc swelling which continued until the age of 16 years when the dose of adalimumab was increased. Case 3 was a 20-year-old woman receiving canakinumab every 8 weeks for systemic symptoms such as fever, headache, vomiting, and abdominal pain and later for sensorineural hearing disturbance on both sides. She had been diagnosed genetically with cryopyrin-associated periodic syndrome with NLRP3 mutation (Y859C) at 7 years old. At 5 years old, she was found to have bilateral optic disc swelling, which continued until the age of 10 years when she began receiving canakinumab (IL-1β inhibitor). Bilateral optic disc swelling might be tentatively designated as a plausible common ocular feature, if it occurred, in autoinflammatory diseases to pay more attention to ophthalmic complications in rare diseases.

Autoinflammatory syndromes in neurology: when our first line of defence misbehaves

Autoinflammatory syndromes result from a defective innate immune system. They are characterised by unexplained fever and systemic inflammation involving the skin, muscle, joints, serosa and eyes, along with elevated acute phase reactants. Autoinflammatory syndromes are increasingly recognised as a cause of neurological disease with a diverse range of manifestations. Corticosteroids, colchicine and targeted therapies are effective if started early, and hence the importance of recognising these syndromes. Here, we review the neurological features of specific autoinflammatory syndromes and our approach (as adult neurologists) to their diagnosis.

Ocular involvement in monogenic autoinflammatory disease

OBJECTIVE

Monogenic Autoinflammatory diseases (AIDs) are a broad spectrum of rare hereditary diseases whose ocular involvement has not been well characterized yet. This systematic review aims to provide an overview of the current knowledge about ocular findings in AIDs.

METHODS

A systematic literature review was conducted using 2 electronic databases, according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. A combination of AIDs and ophthalmology-related search terms were used. All articles were screened by 2 independent reviewers for title, abstract and full text level. We included solely studies that investigated ocular findings in AIDs.

RESULTS

198 papers of 4268 records were retained. Data about 1353 patients with a diagnosis of autoinflammatory disease and ocular involvement were collected (680 CAPS, 211 FMF, 138 TRAPS, 238 Blau, 32 MKD, 21 SIFD, 7 Aicardi Goutières, 3 CANDLE, 8 DADA2, 9 HA20, 6 APLAID). Conjunctivitis was significantly more frequent in CAPS (p < 0.00001), uveitis in Blau, MKD, HA20 and CANDLE (p < 0.00001), papillitis/papilledema in CAPS (p < 0.00001), optic neuritis in Aicardi and DADA2 (p < 0.008), retinal vasculitis in FMF (p < 0.00001), progressive reduction in choroidal thickness in FMF and DADA2 (p < 0.00001), periorbital oedema in TRAPS (p < 0.00001) and retinitis in SIFD (p < 0.00001). Among AIDs with uveitis, granulomatous inflammation was more common in Blau syndrome (p < 0.00001).

CONCLUSION

This systematic literature review characterized the ocular involvement of several AIDs, and the present data may encourage to consider a timely ophthalmological screening program for these rare diseases.

Behçet's Syndrome in a Chinese Pedigree of NLRP3-Associated Autoinflammatory Disease: A Coexistence or Novel Presentation?

Objectives:NLRP3-associated autoinflammatory disease (NLRP3-AID) and Behçet's syndrome (BS) both belong to autoinflammatory diseases and rarely co-occur. Here we reported a Chinese pedigree of NLRP3-AID presented with BS.

Methods: We recorded a Chinese pedigree of NLRP3-AID presented with BS. Whole-exome sequencing was performed to find the hereditary susceptibility gene, and Sanger sequencing was performed on a consecutive cohort of 30 BS patients. We also reviewed the English literature on vasculitis associated with NLRP3-AID.

Results: The proband was a 45-year-old Chinese Han woman. She and her 12-year-old daughter presented with recurrent fevers, cold-induced urticaria, oral, and genital ulcers, conjunctivitis, uveitis, optic atrophy, erythema nodosum, headache, and hearing loss. They were initially suspected of having BS, and both responded poorly to corticosteroids and immunosuppressants, while anti-TNF therapy was moderately effective. Pedigree analysis revealed another four relatives with similar symptoms, and a heterozygous NLRP3 gene mutation c.1316C>T, p.Ala439Val was identified by whole-exome sequencing and Sanger sequencing. However, we did not discover NLRP3 gene mutation by Sanger sequencing in a confirmative cohort of 30 BS cases. A few case reports of vasculitis coexisting with NLRP3-AID, including a case of glomerulonephritis, and five cases of retinal vasculitis, were summarized through literature review.

Conclusions: Our study is the first report of NLRP3-AID associated with BS. The coexistence of NLRP3-AID and BS reveals the extensive heterogeneity of the pathogenesis of systemic autoinflammatory diseases and calls for specific therapeutics.