Functional diversity of NLRP3 gain-of-function mutants associated with CAPS autoinflammation

NLRP3-associated autoinflammatory disease is a heterogenous group of monogenic conditions caused by NLRP3 gain-of-function mutations. The poor functional characterization of most NLRP3 variants hinders diagnosis despite efficient anti-IL-1 treatments. Additionally, while NLRP3 is controlled by priming and activation signals, gain-of-functions have only been investigated in response to priming. Here, we characterize 34 NLRP3 variants in vitro, evaluating their activity upon induction, priming, and/or activation signals, and their sensitivity to four inhibitors. We highlight the functional diversity of the gain-of-function mutants and describe four groups based on the signals governing their activation, correlating partly with the symptom severity. We identify a new group of NLRP3 mutants responding to the activation signal without priming, associated with frequent misdiagnoses. Our results identify key NLRP3 residues controlling inflammasome activity and sensitivity to inhibitors, and antagonistic mechanisms with broader efficacy for therapeutic strategies. They provide new insights into NLRP3 activation, an explanatory mechanism for NLRP3-AID heterogeneity, and original tools for NLRP3-AID diagnosis and drug development.

Gut microbiota alterations are associated with phenotype and genotype in familial Mediterranean fever

OBJECTIVE

FMF is the most common monogenic autoinflammatory disease associated with MEFV mutations. Disease phenotype and response to treatment vary from one patient to another, despite similar genotype, suggesting the role of environmental factors. The objective of this study was to analyse the gut microbiota of a large cohort of FMF patients in relation to disease characteristics.

METHODS

The gut microbiotas of 119 FMF patients and 61 healthy controls were analysed using 16 s rRNA gene sequencing. Associations between bacterial taxa, clinical characteristics, and genotypes were evaluated using multivariable association with linear models (MaAslin2), adjusting on age, sex, genotype, presence of AA amyloidosis (n = 17), hepatopathy (n = 5), colchicine intake, colchicine resistance (n = 27), use of biotherapy (n = 10), CRP levels, and number of daily faeces. Bacterial network structures were also analysed.

RESULTS

The gut microbiotas of FMF patients differ from those of controls in having increased pro-inflammatory bacteria, such as the Enterobacter, Klebsiella and Ruminococcus gnavus group. Disease characteristics and resistance to colchicine correlated with homozygous mutations and were associated with specific microbiota alteration. Colchicine treatment was associated with the expansion of anti-inflammatory taxa such as Faecalibacterium and Roseburia, while FMF severity was associated with expansion of the Ruminococcus gnavus group and Paracoccus. Colchicine-resistant patients exhibited an alteration of the bacterial network structure, with decreased intertaxa connectivity.

CONCLUSION

The gut microbiota of FMF patients correlates with disease characteristics and severity, with an increase in pro-inflammatory taxa in the most severe patients. This suggests a specific role for the gut microbiota in shaping FMF outcomes and response to treatment.

Malignant Peritoneal Mesothelioma Complicating Familial Mediterranean Fever on 18 F-FDG PET/CT

ABSTRACT

A 77-year-old man with a personal history of familial Mediterranean fever presented with a slowly enlarging tumefaction of the left abdominal wall and persistent inflammatory syndrome despite good adherence to colchicine. 18 F-FDG PET/CT showed a hypermetabolic muscular mass of the abdominal wall along with other hypermetabolic lesions including a peritoneal mass and several subcutaneous soft tissue nodules. CT-guided needle biopsy led to the diagnosis of a muscular localization of a malignant peritoneal mesothelioma, which is an extremely rare complication of familial Mediterranean fever. Six courses of chemotherapy with carboplatin and pemetrexed allowed an almost complete response.

Pathogenic variants in the NLRP3 LRR domain at position 861 are responsible for a boost-dependent atypical CAPS phenotype

BACKGROUND

Cryopyrin-associated periodic syndrome (CAPS) is associated with NLRP3 pathogenic variants, mostly located in the NACHT (neuronal apoptosis inhibitor protein, MHC class 2 transcription activator, incompatibility locus protein from Podospora anserina, telomerase-associated protein) domain. Cold-induced urticarial rash is among the main clinical features. However, this study identified a series of 14 patients with pathogenic variants of the Y861 residue (p.Tyr861) of the LRR domain of NLRP3 and minimal prevalence of cold-induced urticarial rash.

OBJECTIVES

This study aimed to address a possible genotype/phenotype correlation for patients with CAPS and to investigate at the cellular levels the impact of the Y861C substitution (p.Tyr861Cys) on NLRP3 activation.

METHODS

Clinical features of 14 patients with CAPS and heterozygous substitution at position 861 in the LRR domain of NLRP3 were compared to clinical features of 48 patients with CAPS and pathogenic variants outside the LRR domain of NLRP3. IL-1β secretion by PBMCs and purified monocytes from patients and healthy donors was evaluated following LPS and monosodium urate crystal stimulation.

RESULTS

Patients with substitution at position 861 of NLRP3 demonstrated a higher prevalence of sensorineural hearing loss while being less prone to skin urticarial. In contrast to patients with classical CAPS, cells from patients with a pathogenic variant at position 861 required an activation signal to secrete IL-1β but produced more IL-1β during the early and late phase of secretion than cells from healthy donors.

CONCLUSIONS

Pathogenic variants of Y861 of NLRP3 drive a boost-dependent oversecretion of IL-1β associated with an atypical CAPS phenotype.

French protocol for the diagnosis and management of familial Mediterranean fever

Familial Mediterranean fever is the most common monogenic auto-inflammatory disease in the world. It mainly affects people originating from the Mediterranean region. The mutated gene is MEFV, which codes for pyrin. Transmission is autosomal recessive. Patients present with recurrent attacks of fever since childhood associated with abdominal and/or thoracic pain lasting an average of 2-3days and a biological inflammatory syndrome. Other symptoms include arthralgia or arthritis in large joints such as the knees and ankles, myalgia in the lower limbs and pseudo-erysipelas in the ankles. The most serious complication is inflammatory amyloidosis, which can lead to kidney failure. Treatment is based on colchicine, which helps to prevent flares and the onset of renal amyloidosis. This paper proposes national guidelines for the diagnosis, management and follow-up of familial Mediterranean fever in France, where we estimate there are between 5000 and 10,000 patients with the disease at all stages of life. The diagnosis is suspected on the basis of clinical and anamnestic factors and confirmed by genetic analysis. These guidelines also suggest a "treat-to-target" approach to disease management, particularly in case of suspected colchicine resistance - a very rare situation that should remain a diagnosis of elimination, especially after colchicine compliance has been verified. Two special situations are also addressed in these guidelines: kidney failure and pregnancy.

Histamine elevation in familial Mediterranean fever: A study from the Juvenile Inflammatory Rheumatism cohort

BACKGROUND

Familial Mediterranean Fever (FMF) is the most frequent monogenic autoinflammatory disease (AID). Some patients have persistent symptoms despite colchicine intake. Mast cells (MC) are innate immune cells involved in inflammatory conditions including AID. Their activation is responsible for various symptoms such as abdominal pain, bloating and pruritus.

OBJECTIVE

Our objective was to evaluate features of a systemic MC activation in FMF adult patients.

METHODS

FMF adult patients prospectively filled a MC activation survey and usual MC mediators (tryptase and histamine in whole blood, plasma and urine) were measured. They were compared with a healthy control group (HC) and a systemic mastocytosis (SM) group. When digestive biopsies were realized during follow-up, MC infiltration in digestive mucosa was analyzed in FMF, in comparison with SM, Crohn disease (CD) and normal biopsies.

RESULTS

Forty-four FMF patients, 44 HC and 44 SM patients were included. Thirty-one (70%) FMF patients had symptoms of mast cell activation, versus 14 (32%) in the HC group (p = 0.0006). Thirty (68%) FMF patients had at least one elevated MC mediator: mainly whole blood histamine, in 19 (43%) and urinary histamine, in 14 (32%), which were significantly higher than in HC subjects. MC infiltration was comparable in FMF digestive biopsies, biopsies of CD and normal biopsies but was lower than in SM biopsies.

CONCLUSION

FMF patients show frequent symptoms of MC activation and an increase of blood or urinary histamine never described before in this disease. This suggests an implication of MC and possibly basophils in FMF pathophysiology.

French practical guidelines for the diagnosis and management of AA amyloidosis

AA amyloidosis is secondary to the deposit of excess insoluble Serum Amyloid A (SAA) protein fibrils. AA amyloidosis complicates chronic inflammatory diseases, especially chronic inflammatory rheumatisms such as rheumatoid arthritis and spondyloarthritis; chronic infections such as tuberculosis, bronchectasia, chronic inflammatory bowel diseases such as Crohn's disease; and auto-inflammatory diseases including familial Mediterranean fever. This work consists of the French guidelines for the diagnosis workup and treatment of AA amyloidosis. We estimate in France between 500 and 700 cases in the whole French population, affecting both men and women. The most frequent organ impaired is kidney which usually manifests by oedemas of the lower extremities, proteinuria, and/or renal failure. Patients are usually tired and can display digestive features anf thyroid goiter. The diagnosis of AA amyloidosis is based on detection of amyloid deposits on a biopsy using Congo Red staining with a characteristic green birefringence in polarized light. Immunohistochemical analysis with an antibody directed against Serum Amyloid A protein is essential to confirm the diagnosis of AA amyloidosis. Peripheral inflammatory biomarkers can be measured such as C Reactive protein and SAA. We propose an algorithm to guide the etiological diagnosis of AA amyloidosis. The treatement relies on the etiologic treatment of the undelying chronic inflammatory disease to decrease and/or normalize Serum Amyloid A protein concentration in order to stabilize amyloidosis. In case of renal failure, dialysis or even a kidney transplant can be porposed. Nowadays, there is currently no specific treatment for AA amyloidosis deposits which constitutes a therapeutic challenge for the future.

Diagnostic and therapeutic algorithms for monogenic autoinflammatory diseases presenting with recurrent fevers among adults

Autoinflammatory diseases (AIDs) are defined as disorders of innate immunity. They were initially defined in contrast to autoimmune diseases because of the lack of involvement of the adaptive immune system and circulating autoantibodies. The four monogenic AIDs first described are called the "historical" AIDs and include: Familial Mediterranean Fever (associated with MEFV mutations), cryopyrinopathies (associated with NLRP3 mutations), Tumor Necrosis Factor Receptor-associated Periodic Syndrome (associated with TNFRSF1A mutations) and Mevalonate Kinase Deficiency (associated with MVK mutations). In the last 10 years, >50 new monogenic AIDs have been discovered due to genetic advances. The most important discovery for adult patients is VEXAS syndrome associated with somatic UBA1 mutations leading to an autoinflammatory disease affecting mostly elderly men. Diagnosis of monogenic AIDs is based on personal and family history and detailed analysis of symptoms associated with febrile attacks, in the context of elevated peripheral inflammatory markers. This review proposes a practical approach of the diagnosis of the main monogenic AIDs among adult patients to guide the clinician.

Mosaic variants in TNFRSF1A: an emerging cause of tumour necrosis factor receptor-associated periodic syndrome

OBJECTIVE

To identify the molecular basis of a systemic autoinflammatory disorder (SAID) evocative of TNF receptor-associated periodic syndrome (TRAPS).

METHODS

(i) Deep next generation sequencing (NGS) through a SAID gene panel; (ii) variant allele distribution in peripheral blood subpopulations; (iii) in silico analyses of mosaic variants using TNF receptor superfamily 1A (TNFRSF1A) crystal structure; (iv) review of the very rare TNFRSF1A mosaic variants reported previously.

RESULTS

In a 36-year-old man suffering from recurrent fever for 12 years, high-depth NGS revealed a TNFRSF1A mosaic variant, c.176G>A p.(Cys59Tyr), which Sanger sequencing failed to detect. This mosaic variant displayed a variant allele fraction of 14% in whole blood; it affects both myeloid and lymphoid lineages. p.(Cys59Tyr), a recurrent germline pathogenic variant, affects a crucial cysteine located in the first cysteine-rich domain (CRD1) and involved in a disulphide bridge. Introduction of a tyrosine at this position is expected to disrupt the CRD1 structure. Review of the three previously reported TNFRSF1A mosaic variants revealed that they are all located in a small region of CRD2 and that germinal cells can be affected.

CONCLUSION

This study expands the localization of TNFRSF1A mosaic variants to the CRD1 domain. Noticeably, residues involved in germline TNFRSF1A mutational hot spots can also be involved in post-zygotic mutational events. Including our study, only four patients have been thus far reported with TNFRSF1A mosaicism, highlighting the need for a high-depth NGS-based approach to avoid the misdiagnosis of TRAPS. Genetic counselling has to consider the potential occurrence of TNFRSF1A mosaic variants in germinal cells.

AA amyloidosis complicating cryopyrin-associated periodic syndrome: a study of 86 cases including 23 French patients and systematic review

OBJECTIVE

Cryopyrin-associated periodic syndrome (CAPS) is a rare but treatable inherited autoinflammatory condition including familial cold autoinflammatory syndrome (FCAS), Muckle-Wells syndrome (MWS) and chronic infantile neurologic cutaneous articular syndrome (CINCA). Our objective was to describe the main features of CAPS AA amyloidosis (AA-CAPS) associated and the efficacy of IL-1 inhibitors in this indication.

METHODS

Retrospective study in France associated with a systematic literature review.

RESULTS

Eighty-six patients were identified: 23 new French cases and 63 from the literature, with a median age at amyloidosis diagnosis of 39 years old. CAPS subtypes were MWS (n = 62), FCAS (n = 9), frontier forms between MWS and FCAS (n = 12) and between CINCA and MWS (n = 3). NLRP3 had been sequenced in 60 patients (70%) and the most frequent mutation was R260W (60%). Three AA-CAPS patients displayed somatic NLRP3 mutations. Death occurred in 35 patients (41%), none of whom having ever received IL-1 inhibitors. Twenty-eight patients (33%) received IL-1 inhibitors, with a >50% decrease in proteinuria in 89% of cases.

CONCLUSION

AA amyloidosis can occur in nearly all CAPS subtypes. IL-1 inhibitors are effective, underlining the necessity of an early diagnosis of CAPS in order to start this treatment as soon as possible among AA-CAPS patients.

Vasculitis and familial Mediterranean fever: Description of 22 French adults from the juvenile inflammatory rheumatism cohort

Objective

The frequency of vasculitis may be increased in patients with Familial Mediterranean Fever (FMF), according to several studies. Our aim was to assess the characteristics of French adult patients with both diseases.

Methods

Patients with vasculitis were selected from patients followed for FMF in the French JIR-cohort.

Results

Twenty-two patients were included [polyarteritis nodosa (PAN) n = 10, IgA vasculitis n = 8, unclassified vasculitis n = 2, granulomatosis with polyangiitis n = 1, and microscopic polyangiitis n = 1]. Pathogenic mutations in exon 10 were found in all 21 patients (96%) for which MEFV testing results were available, and 18 (82%) had two pathogenic mutations. Histology showed vasculitis in 59% of patients. Most patients with FMF-associated PAN were HBV-negative and had an inactive FMF before PAN onset, and 40% had a peri-renal or central nervous system bleeding. Most patients with FMF-associated IgA vasculitis had an active FMF before vasculitis onset, and 25% had digestive bleeding. Both patients with unclassified vasculitis had ischemic and/or hemorrhagic complications.

Conclusion

This study confirms the predominance of PAN and IgA vasculitis in patients with FMF and the high frequency of bleeding in FMF-associated PAN. FMF should be considered in case of persistent symptoms and/or inflammatory syndrome despite vasculitis treatment in Mediterranean patients.

Amyloidosis from the patient perspective: the French daily impact of amyloidosis study

BACKGROUND

Amyloidosis is a complex group of rare conditions. For patients, amyloidosis is severely debilitating: physically and psychologically. Currently, data are lacking to evaluate the medical, economic, and social burden of systemic amyloidosis.

OBJECTIVE

To analyse the patient burden according to the main types of systemic amyloidosis.

METHODS

The French Daily Impact of Amyloidosis study was an observational, cross-sectional and non-interventional study. Adults diagnosed with light chain (AL), transthyretin (ATTR), amyloid A (AA) and other rare forms of amyloidosis were eligible. Data regarding amyloidosis prevalence, diagnosis, management, and impact on everyday life were collected using a study-specific survey built by the Association Française Contre l'Amylose (AFCA) and the four French National Referral Centres for Amyloidosis.

RESULTS

A total of 603 patients, predominantly male (65%) with an average age of 66.8 years, including 170 AL, 224 ATTRv, 109 ATTRwt and 25 AA amyloidosis patients, completed the study-specific survey. The median delay from presentation to confirmed diagnosis was 27.4 months but varied according to amyloidosis type. Patients before diagnosis had breathlessness (49%), tingling sensation (33%), pain (28%), difficulty in walking (28%) and weight loss (22%). Amyloidosis was most frequently suspected (49%) and confirmed (57%) in local hospitals but managed in French amyloidosis referral centres (58%). Patients often reported problems with mobility, usual activities, pain/discomfort and anxiety/depression, but not with self-care.

CONCLUSIONS

Systemic amyloidosis severely impacts daily life. The delay to confirmed amyloidosis diagnosis needs to be reduced. Early, effective treatment is required to optimise patient benefits.

Neurological manifestations in mevalonate kinase deficiency: A systematic review

INTRODUCTION

Mevalonate kinase deficiency (MKD) is a monogenic auto-inflammatory disease. Its manifestations range from partial MKD to mevalonic aciduria (MVA). All patients display a periodic fever, and MVA patients additionally exhibit severe neurological involvement. The objective of this work was to describe neurological manifestations of MKD.

METHODS

A systematic literature review was performed from January 1990 to January 2022. Forty-five patients from 18 case reports and five cohort studies were included in the analysis.

RESULTS

In cohort studies, the most-reported manifestations were headaches (41%) and fatigue (31%). Serious involvements including ataxia and developmental delay were described less than 1% of patients but 22-31% of case reports. They consistently appeared in the first years of life. Retinal dystrophy was frequently reported (31%) in case reports. Other manifestations, including uveitis, aseptic meningitis, and stroke remained rare.

DISCUSSION

Severe neurological manifestations are rare in MKD but are responsible for major functional disabilities. They are present at onset and never appear at follow-up of patients with mild MKD. Conversely, headaches and fatigue are frequent symptoms that should be investigated. Visual examinations should be performed on the appearance of visual symptoms. The efficacy of anti-IL-1β therapy on neurological manifestations should be further investigated.

COVID-19 infection among patients with autoinflammatory diseases: a study on 117 French patients compared with 1545 from the French RMD COVID-19 cohort: COVIMAI - the French cohort study of SARS-CoV-2 infection in patient with systemic autoinflammatory diseases

Objective

There is little known about SARS-CoV-2 infection in patients with systemic autoinflammatory disease (SAID). This study aimed to describe epidemiological features associated with severe disease form and death. Mortality between patients with and without SAID hospitalised for SARS-CoV-2 infection was compared.

Methods

A national multicentric prospective cohort study was conducted from the French Rheumatic and Musculoskeletal Diseases (RMD) COVID-19 cohort. Patients with SAID were matched with patients with non-SAID on age±7 years, gender and number of comorbidities to consider important confounding factors. Impact of SAID on severity of SARS-CoV-2 infection was analysed using multinomial logistic regression for severity in three classes (mild, moderate and severe with mild status as reference). Fine-Gray regression model for length of hospital stay and binomial logistic regression model for risk of death at 30 days.

Results

We identified 117 patients with SAID (sex ratio 0.84, 17 children) and compared them with 1545 patients with non-autoinflammatory immune-mediated inflammatory disorders (non-SAID). 67 patients had a monogenic SAID (64 with familial Mediterranean fever). Other SAIDs were Behçet’ disease (n=21), undifferentiated SAID (n=16), adult-onset Still disease (n=9) and systemic-onset juvenile idiopathic arthritis (n=5). Ten adults developed severe form (8.6%). Six patients died. All children had a benign disease. After matching on age±7 years, sex and number of comorbidities, no significant difference between the two groups in length of stay and the severity of infection was noted.

Conclusion

As identified in the whole French RMD COVID-19 cohort, patients with SAID on corticosteroids and with multiple comorbidities are prone to develop more severe COVID-19 forms.

Poor performance of albumin or protein-adjusted plasma calcium to diagnose dyscalcemia in hospitalized patients: A confirmatory study in a general internal medicine department

INTRODUCTION

Hypo- and hypercalcemia are common and some causes require urgent diagnosis and treatment. Measurement of ionized calcium is the reference test to diagnose calcium disorders but total calcium adjusted for protein or albumin concentration is more often used.

METHODS

Patients hospitalised in a general internal medicine department from September 2013 to December 2015 who had a total plasma calcium concentration and a serum albumin or protein concentration measured within 24h of a ionized calcium blood measurement were included. Total calcium was adjusted for protein or albumin concentration using widely used formulas and compared to ionized calcium as the gold standard.

RESULTS

Among 210 included patients, 46 (22%) had hypocalcemia, 124 (59%) normocalcemia and 40 (19%) hypercalcemia according to ionized calcium concentration. Total calcium had 50% sensitivity and 95% specificity to diagnose hypocalcemia and a 93% sensitivity and 89% specificity to diagnose hypercalcemia. Adjusting total calcium for protein or albumin concentrations did not increase and sometimes decreased diagnostic accuracy.

CONCLUSION

Total calcium, with or without albumin/protein adjustment, is poorly sensitive to screen for hypocalcemia. Unadjusted total calcium is as sensitive as protein- or albumin-adjusted total calcium to screen for hypercalcemia. These data argue against the use of albumin- or protein-adjusted calcium. Ionized calcium measurement should be performed to confirm dyscalcemia in patients with abnormal total calcium concentration and to rule out hypocalcemia in patients with total calcium concentration in the lower range of normal values.

AA amyloidosis complicating monoclonal gammopathies, an unusual feature validating the concept of "monoclonal gammopathy of inflammatory significance"?

INTRODUCTION

AL amyloidosis is caused by the proliferation of an immunoglobulin-secreting B cell clone. AA amyloidosis is a rare complication of chronic inflammation. However, some patients present with diseases combining monoclonal immunoglobulin production and chronic inflammation. The aim of this work was to describe cases of AA amyloidosis associated with monoclonal gammopathies.

PATIENTS AND METHODS

We reviewed all patients reported in French national amyloid centres presenting with AA amyloidosis and monoclonal gammopathy and performed a literature review. The quality of AA amyloidosis diagnosis and the causal relationship with monoclonal gammopathy were assessed.

RESULTS

In total, four patients from our centres and eight from the literature fulfilled the inclusion criteria. The haematological disorders presenting with monoclonal gammopathy were as follows: Waldenström macroglobulinaemia (n = 8), Schnitzler syndrome (n = 2), multiple myeloma (n = 1) and monoclonal gammopathy of undetermined significance (n = 1). Treatment strategies varied among the cases, with the treatment of the haematological disorder in 4 and anti-inflammatory treatment in 2.

CONCLUSION

Monoclonal gammopathies might be a rare and poorly known cause of AA amyloidosis. Such monoclonal gammopathies could be named "monoclonal gammopathies of inflammatory significance."

DADA2 diagnosed in adulthood versus childhood: A comparative study on 306 patients including a systematic literature review and 12 French cases

BACKGROUND

Deficiency of adenosine deaminase 2 (DADA2) is a rare autoinflammatory disease usually presenting before the age of 10 years. Non-specific clinical features or late-onset presentation may delay its diagnosis until adulthood.

OBJECTIVE

To determine whether DADA2 diagnosed in adulthood is associated with specific characteristics compared to DADA2 diagnosed in childhood.

METHODS

We pooled a cohort of 12 adult DADA2 patients followed in France with cases identified through a systematic literature review. For each patient, we determined the type of clinical presentation and assessed six key organ involvements.

RESULTS

A total of 306 cases were included. Among the 283 patients with available data regarding age at diagnosis, 140 were diagnosed during adulthood and 143 during childhood. The vascular presentation of DADA2 was more frequent in the adult diagnosis group (77.9% vs. 62.9%, p < 0.01), whereas the hematological presentation (bone marrow failure) prevailed in the pediatric diagnosis group (10.0% vs. 20.3% p = 0.02). In patients with vasculopathy, severe skin manifestations developed in 35% and 10% of the adult and pediatric diagnosis groups, respectively. Conversely, fewer strokes occurred in the adult group presenting with systemic vasculopathy (54% vs. 81%). Symptomatic humoral immune deficiency (HID) was rarely a clinical presentation in itself (5% and 2.8%) but accompanied other phenotypes of DADA2, especially the hematological phenotype in the adult group (33% vs. 4%).

CONCLUSION

DADA2 diagnosed in adulthood presents more often with a vascular phenotype and less often with bone marrow failure than DADA2 diagnosed in childhood. Adults diagnosed with DADA2 vasculopathy display more severe skin involvement but fewer strokes.

AA Amyloidosis in the Course of HIV Infection: A Report of 19 Cases Including 4 New French Cases and a Comprehensive Review of Literature

INTRODUCTION

HIV infection has been recently retained as an unclear cause of AA amyloidosis. Our aim was to investigate cases of AA amyloidosis associated with HIV infection to understand if it could be considered as a cause of AA amyloidosis.

METHODS

A comprehensive literature review was conducted as well as retrospective study from French cases collected from our national reference center for AA amyloidosis.

RESULTS

Altogether, 19 patients with AA amyloidosis and HIV infection were found with 68% of men and median age at amyloidosis diagnosis of 38 years (range 28-75 years). Clinical presentation was nephrotic syndrome in 94% (n = 17/18). Among patients with renal involvement and assessable outcome (n = 17), 11 (64.7%) progressed to chronic kidney disease, with 6 (35%) end-stage renal disease. Seventy-five percent of patients had uncontrolled HIV infection and 71.4% CD4 counts <400/mm3 at amyloidosis diagnosis. Repeated or chronic bacterial or fungal infection was found in 47% of cases and a history of parenteral drug use in 55% of patients. Three patients had no classical or at least no suspected AA amyloidosis cause found or reported.

CONCLUSIONS

AA Amyloidosis is a rare condition in HIV patients with common renal involvement and significant risk of progression to chronic renal insufficiency. Because of the frequency related to other inflammatory conditions in this population, HIV is probably not an independent risk factor for AA amyloidosis.

Is neutrophilic dermatosis a manifestation of familial Mediterranean fever?

Objectives: Familial Mediterranean fever (FMF) is the most frequent monogenic autoinflammatory disease. It is associated with MEFV mutations. Its main features are recurrent episodes of fever and serositis. Patients can display dermatological manifestations such as erysipelas-like erythema, generally considered as a neutrophilic dermatosis (ND). It has been suggested that FMF can be associated with other types of ND. Our aim was to perform a systematic review of the literature to assess the link between ND and FMF.Method: A systematic review of the literature was performed using MEDLINE from 1946 to 2018. Three independent investigators identified reports of non-erysipelas-like erythema neutrophilic dermatosis (NEND) associated with FMF, selected the criteria to establish the diagnosis of FMF and ND, and evaluated the link between the two conditions. FMF-associated NEND was supported by confirmation of both diagnoses and exclusion of other causes of ND.Results: Eighteen articles were selected. Nine articles reported FMF patients with the following NEND: neutrophilic panniculitis (n = 4), Sweet syndrome (n = 6), and pyoderma gangrenosum (n = 1). None of these cases was supported by histological confirmation, fulfilled diagnostic criteria for definitive or probable FMF, or confirmed the exclusion of all the most frequent diseases associated with NEND. As a result, there is insufficient evidence to support a potential relationship between NEND and FMF.Conclusions: The association between FMF and NEND remains unclear. In FMF patients with NEND, every differential diagnosis and alternative cause of NEND should be excluded before drawing any conclusions about a potential causal relationship.

La fièvre méditerranéenne familiale est-elle uns situation à risque de développer une forme grave d’infection par la COVID19 ? Résultat d’une étude rétrospective sur 627 patients en période et zone endémique en France

Introduction

La nouvelle pandémie mondiale (COVID19) causée par le coronavirus 2 du syndrome respiratoire aigu sévère (SRAS-CoV-2) est responsable de nombreux décès dans le monde entier au cours des derniers mois. Au cours des formes graves, il a été noté une réponse inflammatoire exagérée connue sous le nom de “orage cytokinique”. Ceci a soulevé la question de la sensibilité et de la gravité de l’infection par le SRAS-CoV2 chez les patients présentant une hyperactivation génétique de l’immunité innée tels que la fièvre méditerranéenne familiale (FMF). En outre, les patients avec FMF prennent de la colchicine au long cours, médicament qui a été testé chez des patients infectés par le SRAS-CoV2 avec des résultats contradictoires [1].

Patients et méthodes

Étude menée sur l’infection par le SRAS-CoV2 chez les patients atteints de FMF suivis dans 2 sites du centre de référence national des maladies autoinflammatoires en région parisienne et inclus dans la JIR cohorte, une base de données européenne multicentrique. Les patients adultes et pédiatriques inclus répondaient aux critères internationaux de FMF et avaient un diagnostic génétique confirmé.

Résultats

Les patients identifiés (n = 627) ont été invités à répondre à un bref questionnaire soit en consultation, soit par téléphone, soit par courrier électronique sur une possible infection par le SARS-CoV2 pendant la période de mars à juin 2020 ; 342 patients ont répondu à l’enquête. Le diagnostic était retenu si le patient présentait des symptômes cliniques avec PCR ou sérologie positive ou scanner thoracique typique. Au total, 27 patients FMF (7,8 % des répondants ; sexe ratio 1/1) ont contracté le virus. Tous les 27 patients FMF-COVID+ sauf un prenaient de la colchicine quotidiennement depuis une période médiane de 23 ans, la dose moyenne de colchicine était de 1 mg/jour. Quatre recevaient en plus un inhibiteur de l’IL-1. Parmi les 27 patients FMF-COVID+, sept symptomatiques ont été hospitalisés (25 %) et six ont eu besoin d’oxygène ; trois (11 %) ont développé un syndrome de détresse respiratoire aiguë nécessitant des soins intensifs pour une ventilation mécanique et une hémodialyse. Deux patients sont décédés (7 %) mais présentaient respectivement 3 et 4 comorbidités pour une infection grave par le SRAS-CoV2 ; le troisième patient, âgé de 40 ans, souffrait d’hypertension et d’obésité. Les patients âgés de plus de 65 ans représentaient 17 % de l’ensemble de la cohorte FMF-COVID +  ; 75 % ont été hospitalisés et ont eu besoin d’oxygène ; l’un d’eux est décédé. Trois patients FMF-COVID +  avaient une amylose AA : 2 ont été hospitalisés et un est décédé. Aucun traitement anti-viral supplémentaire n’a été administré. Les 5 survivants après hospitalisation sont rentrés chez eux. Aucun d’entre eux n’a présenté de signes cliniques de crise de FMF lors de l’infection par le SRAS-CoV2.

Discussion

Le profil des patients FMF atteints d’une forme grave ou potentiellement mortelle par le SRAS-CoV2 était le même que celui de la population générale. Ainsi, seuls les patients FMF présentant des facteurs de risque connus (tels que âge avancé, maladie rénale chronique, hypertension, maladie vasculaire, obésité et dysfonctionnement pulmonaire) ont développé une infection grave par le SARS-CoV2 [2]. Cette étude n’est pas en faveur d’un surrisque en soi de développer une infection sévère à SRAS-CoV2 en présence d’une maladie autoinflammatoire monogénique touchant un inflammasome. Aucune conclusion formelle ne peut être tirée sur l’effet préventif de la colchicinothérapie au long cours, bien que ce travail rétrospectif porte sur une large cohorte de patients traités par colchicine depuis plusieurs années. Il est difficile de conclure à l’efficacité du traitement par inhibiteur d’IL1 vis-à-vis l’infection par le SRAS-CoV-2 chez les patients FMF, mais 50 % des patients traités au long cours sont décédés mais avaient plusieurs comorbidités ; et des publications récentes semblent plaider en faveur de l’efficacité de l’anakinra dans l’infection grave par le SRAS-CoV-2 [3].

Conclusion

La FMF ne semble pas constituer un facteur de risque de développer une forme sévère d’infection par SARS-CoV2 chez les patients traités au long cours par de la colchicine quotidienne, par rapport à la population générale.

Infections and AA amyloidosis: An overview

BACKGROUND

Amyloidoses are a heterogeneous group of systemic diseases characterised by extracellular accumulation of insoluble amyloid fibrils derived from unfolded proteins. Inflammatory (AA) amyloidosis can complicate various inflammatory disorders that are associated with a sustained acute phase response and serum amyloid A (SAA) protein overproduction. Chronic infections were the first recognised cause of amyloidoses. However, with the better management of underlying diseases, the frequency of AA amyloidosis is decreasing.

PURPOSE

The aim of this overview was to discuss the several infections associated with AA amyloidosis and the relative frequency of infections as aetiological factors.

METHODS

A search of the literature was performed using the PubMed database using the MeSH terms "Amyloidosis" and "Infections," from inception to December 31st, 2019. Articles written in other languages than English or French were excluded.

RESULTS

The frequency of AA amyloidosis secondary to infections decreased from more than 50% to less than 20% after the 2000s, with a parallel increase in the frequency of AA amyloidosis secondary to inflammatory diseases and to an unknown cause.

CONCLUSION

Whereas new antibiotics have been developed and sanitary conditions are better, infections still represent 5%-30% of the causes of AA amyloidosis, including in developed countries. These data argue for better screening of chronic infections to prevent AA amyloidosis and the development of new strategies to manage recurrent infections.

POS1343 ABNORMAL ELECTROCHEMICAL SKIN CONDUCTANCE VALUES IN PATIENTS WITH AA AMYLOIDOSIS

Background:

Clinical manifestations are scarce in AA amyloidosis (AAA) and, contrary to other types of amyloidosis, involvement of the peripheral nervous system was rarely reported in AAA. However, the usual absence of hypertension despite chronic renal failure and the digestive involvement may be secondary to dysautonomia, but the autonomic nervous system has rarely been studied in AAA (1). Measure of the electrochemical skin conductance (ESC) is a simple and reproducible method to evaluate the function of eccrine sweat glands, which are innervated by small non-myelinated C fibers, and patients with AL and hereditary transthyretin amyloidoses show decreased ESC values (2,3).

Objectives:

To evaluate ESC values by Sudoscan in patients with AAA.

Methods:

Patients diagnosed as having AAA based on positive immunohistochemistry with an anti-serum amyloid A antibody followed at the national reference center for AAA in Tenon Hospital between July, 2017 and September, 2020, were routinely assessed for ESC with FDA approved Sudoscan (Impeto Medical, Paris, France). An ESC value above 60 microSiemens (µS) or 70 µS were considered normal for hands or feet, respectively. Categorical variables are reported as percentages and continuous variables are expressed as means±standard deviation. Correlations between age, body mass index (BMI), hemoglobin levels, C-reactive protein levels, estimated glomerular filtration rate using the Chronic Kidney Disease Epidemiology Collaboration equation (defined as 0 for dialysis patients) and ESC values were calculated using the nonparametric Spearman test. GraphPad Prism Version 7 software (GraphPad Software, San Diego, California, USA) was used for statistical analyses. A p-value <0.05 was considered as statistically significant.

Results:

Overall, 32 patients (16 women) were included, with a mean age of 57.4±13.6 years and a mean BMI of 25.2±6.8 kg/m2. Six (19%) had diabetes mellitus, and 5 (16%) had a kidney transplantation. The main causes of AAA were: monogenic autoinflammatory diseases (n=11, 34%, including 9 patients with familial Mediterranean fever), chronic and/or recurrent infections (n=5, 16%), obesity (n=3, 9%) and undefined (n=3, 9%). The mean hands’ ESC values was normal at 65.5±21.1 µS, although 8 (25%) patients had ESC values below 60 µS, including 2 diabetic patients. In contrast, the mean feet’s ESC values was abnormal at 62.7±23.7 µS, including half of the patients with ESC values below 70 µS (2 diabetic patients). Eight patients had abnormal ESC values only for feet, and 1 had abnormal values only for hands. Apart from a significant correlation between feet and hands’ ESC values (p<0.0001), only the estimated glomerular filtration rate was significantly associated with hands’ ESC values (p<0.01).

Conclusion:

To our knowledge, this is the first study to assess ESC in AAA. Feet’s ESC values were moderately impaired in half of the patients with AAA. Therefore, this study reinforces the previously reported alterations in the autonomic nervous system in patients with AAA that should probably be searched for in these patients. In addition, the identification of an alteration of the ESC values cannot allow to distinguish the type of amyloidosis.

References:

[1]Nussinovitch U, Volovitz B, Nussinovitch M, Lidar M, Feld O, Nussinovitch N, et al. Abnormal heart rate variability in AA amyloidosis of familial Mediterranean fever. Amyloid 2011;18:206–10.

[2]Montcuquet A, Duchesne M, Roussellet O, Jaccard A, Magy L. Electrochemical skin conductance values suggest frequent subclinical autonomic involvement in patients with AL amyloidosis. Amyloid 2020;27:215–6.

[3]Fortanier E, Delmont E, Verschueren A, Attarian S. Quantitative sudomotor test helps differentiate transthyretin familial amyloid polyneuropathy from chronic inflammatory demyelinating polyneuropathy. Clin Neurophysiol 2020;131:1129–33.

Disclosure of Interests:

None declared

[Familial Mediterranean fever in 2020]

Familial Mediterranean fever is the most frequent autoinflammatory disease with autosomal recessive transmission. Most patients carry mutations in the MEFV gene encoding the protein marenostrin/pyrin. It is characterised by short ant recurrent attacks of fever and serositis with abdominal or thoracic pain, usually lasting less than 3 days, raised inflammatory biologic markers in an individual of Mediterranean origin. Colchicine has been shown to be effective in prevention of inflammatory attacks and development of amyloidosis which is responsible of nephrotic syndrome and chronic renal failure. Better knowledge in pathogenic mechanisms permitted identification of interleukin-1 beta (Il-1 β) as the main cytokine target. Anti-IL-1 therapy must be considered as a second line treatment in case of persistent inflammation or colchicine intolerance.

"Helicobacter pylori in familial mediterranean fever: A series of 120 patients from literature and from france"

INTRODUCTION

Familial Mediterranean Fever (FMF), the most common monogenic auto-inflammatory disease, is characterized by recurrent febrile abdominal pain. Helicobacter pylori infection (HPI), one of the most frequent infections worldwide, can mimic an FMF attack.

OBJECTIVES

Identify FMF patients with HPI in a cohort of French FMF patients and the literature and identify features allowing to distinguish HPI from an FMF attack.

METHODS

A retrospective study of all HPI cases was performed on the cohort of FMF patients fulfilling the Livneh criteria from the French Reference Center for rare Auto-Inflammatory Diseases and Amyloidosis (CEREMAIA). A systematic literature review of HPI in FMF patients was conducted according to the PRISMA guidelines.

RESULTS

Eight French patients developed HPI, whose symptoms of epigastralgia, diarrhea, anorexia/weight loss, and nausea/vomiting differed from their typical abdominal FMF attacks. A total of 112 FMF patients with HPI have been described in the literature, including 61 adults. Diagnosis of HPI was made by gastroscopy (n = 43), labelled urea test (n = 55) or IgG serology by ELISA (n = 12). When performed, C-reactive protein was always elevated. Ten cases of interaction between colchicine and antibiotic therapy for HPI (clarithromycin (n = 9) and azithromycin (n = 1)) were reported.

CONCLUSION

We described a total of 120 patients with typical FMF and HPI. When FMF patients develop atypical abdominal symptoms, upper gastrointestinal endoscopy with biopsies is essential to eliminate underlying HPI. Untreated HPI can lead to misdiagnosis of colchicine resistance with inappropriate prescription of an interleukin-1 inhibitor at a non-negligible cost.

Tumor necrosis factor receptor-1 assciated periodic syndrome (TRAPS) related AA amyloidosis: a national case series and systematic review

OBJECTIVES

Tumor necrosis factor (TNF) receptor-1 associated periodic syndrome (TRAPS) is a rare autosomal dominant autoinflammatory disorder associated with mutations in the TNF receptor super family 1A (TNFRSF1A) gene. AA amyloidosis (AA) is the most severe complication of TRAPS. To study the occurrence and prognosis of AA in TRAPS, we conducted a retrospective study of all French cases and a systematic literature review.

METHODS

This case series includes TRAPS patients followed by our center from 2000 to 2020 presenting with histologically confirmed AA. We conducted a systematic literature review on the PubMed and Embase databases for articles published up February 2021 following the PRISMA guidelines and using the keywords: amyloidoisis, amyloid, TNF receptor-associated periodic syndrome, TNF Receptor-associated Periodic Syndrome, Tumor necrosis factor receptor-associated periodic syndrome, TRAPS, TNFRSF1A, Familial Hibernian fever and Hibernian Familial Fever.

RESULTS

A total of 41 TRAPS with AA were studied: 3 new patients and 38 cases from the literature. AA diagnosis preceded that of TRAPS in 96% of cases, and 17/36 (47%) required renal replacement therapy. Death occurred in 5/36 (14%) with a median follow-up of 23 months. Effect of biologics on AA were available for 21 regimens in 19 patients: 10 improved renal function, 7 stabilized and 4 worsened. Four patients (36% of transplanted patients) relapse AA on kidney graft (only one under etanercept).

CONCLUSION

TRAPS is revealed by AA in most cases. Therefore, clinical features of TRAPS should be screened for in AA patients. IL-1 antagonist can help to normalize inflammation and to preserve renal function.

β-Glucan-induced reprogramming of human macrophages inhibits NLRP3 inflammasome activation in cryopyrinopathies

Exposure of mononuclear phagocytes to β-glucan, a naturally occurring polysaccharide, contributes to the induction of innate immune memory, which is associated with long-term epigenetic, metabolic, and functional reprogramming. Although previous studies have shown that innate immune memory induced by β-glucan confers protection against secondary infections, its impact on autoinflammatory diseases, associated with inflammasome activation and IL-1β secretion, remains poorly understood. In particular, whether β-glucan-induced long-term reprogramming affects inflammasome activation in human macrophages in the context of these diseases has not been explored. We found that NLRP3 inflammasome-mediated caspase-1 activation and subsequent IL-1β production were reduced in β-glucan-reprogrammed macrophages. β-Glucan acted upstream of the NLRP3 inflammasome by preventing potassium (K+) efflux, mitochondrial ROS (mtROS) generation, and, ultimately, apoptosis-associated speck-like protein containing a CARD (ASC) oligomerization and speck formation. Importantly, β-glucan-induced memory in macrophages resulted in a remarkable attenuation of IL-1β secretion and caspase-1 activation in patients with an NLRP3-associated autoinflammatory disease, cryopyrin-associated periodic syndromes (CAPS). Our findings demonstrate that β-glucan-induced innate immune memory represses IL-1β-mediated inflammation and support its potential clinical use in NLRP3-driven diseases.

AA Amyloidosis Secondary to Primary Immune Deficiency: About 40 Cases Including 2 New French Cases and a Systematic Literature Review

BACKGROUND

Primary immune deficiencies (PIDs) are a heterogeneous group of disorders resulting from defects in immune system. They lead to increased susceptibility to infections and immune dysregulation. The resulting chronic inflammation can induce long-term complications, including AA amyloidosis (AAA).

OBJECTIVES

To present the French cases of PID-related AAA and perform a systematic literature review to determine its main features and predisposing factors.

METHODS

A systematic literature review was performed by searching MEDLINE up until 2019. New French cases were identified with the help of the Reference Center for Auto-Inflammatory Diseases and AA Amyloidosis and the Reference Center for Hereditary Immune Deficiencies.

RESULTS

Forty patients were identified including 2 new French cases. PIDs were varied: immunoglobulin deficits (n = 30), chronic granulomatous disease (n = 3), hyper-IgM syndrome (n = 3), hereditary complete C4 deficiency (n = 1), leucocyte adhesion deficiency type 1 (n = 1), hyper-IgE syndrome (n = 1), and Chediak-Higashi syndrome (n = 1). The mean age at PID diagnosis was 22.2 ± 16.02 years. Renal involvement was the most common manifestation of AAA (80%). Infections were extremely heterogeneous; bacterial infection with pulmonary involvement was the most frequent. Bronchiectasis was particularly common (52.5%). The delay between the first symptoms of PID and AAA diagnosis was 16.18 ± 7 years. Thirteen concomitant diagnoses were made. Twenty patients died during follow-up.

CONCLUSION

AAA is a rare life-threatening complication of PID, especially in cases of long diagnostic and therapeutic delays. Bronchiectasis should be considered as a warning sign of chronic inflammation and increased risk of AAA.

Long-Term Follow-Up and Optimization of Interleukin-1 Inhibitors in the Management of Monogenic Autoinflammatory Diseases: Real-Life Data from the JIR Cohort

Objectives: The major role of interleukin (IL)-1 in the pathogenesis of hereditary recurrent fever syndromes favored the employment of targeted therapies modulating IL-1 signaling. However the best use of IL1 inhibitors in terms of dosage is difficult to define at present.

Methods: In order to better understand the use of IL1 inhibitors in a real-life setting, our study assessed the dosage regimens of French patients with one of the four main hereditary recurrent fever syndromes (Familial Mediterranean Fever (FMF), TNF receptor associated periodic syndrome (TRAPS), cryopyrin associated periodic fever (CAPS) and mevalonate kinase deficiency). The patients were retrieved retrospectively from the JIR cohort, an international platform gathering data of patients with pediatric inflammatory diseases.

Results: Forty five patients of the JIR cohort with a hereditary recurrent fever syndrome had received at least once an IL1 inhibitor (anakinra or canakinumab). Of these, 43% received a lower dosage than the one suggested in the product recommendations, regardless of the type of the IL1 inhibitor. Especially patients with FMF and TRAPS seemed to need lower treatment regimens; in our cohort none of the FMF or TRAPS patients received an intensified dose of IL-inhibitor. On-demand treatment with a short half-life IL-1 inhibitor has also been used successfully for some patients with one of these two conditions The standard dose was given to 42% of the patients; whereas an intensified dose of IL-1 inhibitors was given to 15% of the patients (44% of CAPS patients and 17% of mevalonate kinase deficiency patients). In our cohort each individual patient’s need for treatment seemed highly variable, ranging from on demand treatment regimens to intensified dosage maintenance therapies depending on the activity and the severity of the underlying disease.

Conclusion: IL-1 inhibitors are a good treatment option for patients with a hereditary recurrent fever syndrome, but the individual need of the dosage of IL-1 inhibitors to control the disease effectively seems highly variable. Severity, activity but also the type of the underlying disease, belong to the parameters underpinning the treat-to-target strategy implemented in an everyday life practice.

[Periodic fever syndrome associated with mutations in the TNF type 1 receptor gene: A differential diagnosis of familial Mediterranean fever that should not be overlooked in patients of Mediterranean origin]

INTRODUCTION

Tumor Necrosis Factor Type 1 Receptor Associated Periodic Syndrome (TRAPS) is a rare autosomal dominant autosomal autoinflammatory disease associated with mutations in the TNF type 1 receptor gene (TNFRSF1A). It is characterized by relatively long recurrent febrile seizures with an average duration of 7 days accompanied by arthralgia, myalgia, and usually a rash. In a patient of Mediterranean origin with recurrent fever, familial Mediterranean fever is the first diagnosis to be suspected by argument of frequency.

METHODS

A retrospective observational study was conducted on patients from Mediterranean origin followed for TRAPS and included in the "Juvenile Inflammatory Rheumatism" (JIR) observational cohort in the national French autoinflammatory center. The age of onset of symptoms, age of diagnosis, number of years of wandering and treatments received were collected for each index case.

RESULTS

Nine patients from 6 families of Mediterranean origin were included. A molecular diagnosis confirmed TRAPS in all patients. The median age at diagnosis was 26 years, the mean number of years of wandering was 17 years. The diagnosis of FMF was made first in all patients. AA amyloidosis revealed TRAPS in 2 patients. Colchicine was started without any efficacy in all cases. Five patients were treated with interleukin-1 inhibitory biotherapy with 100% efficacy.

CONCLUSION

In a patient of Mediterranean origin presenting with recurrent febrile abdominal pain of AA amyloidosis, the first diagnosis to be suspected is FMF. Long relapses, dominant transmission, a non-Mediterranean relative, and the ineffectiveness of colchicine should evoke TRAPS.

Fast diagnostic test for familial Mediterranean fever based on a kinase inhibitor

BACKGROUND AND OBJECTIVE

Familial Mediterranean fever (FMF) is the most frequent hereditary autoinflammatory disease. Its diagnosis relies on a set of clinical criteria and a genetic confirmation on identification of biallelic pathogenic MEFV variants. MEFV encodes pyrin, an inflammasome sensor. Using a kinase inhibitor, UCN-01, we recently identified that dephosphorylation of FMF-associated pyrin mutants leads to inflammasome activation. The aim of this study was to assess whether quantifying UCN-01-mediated inflammasome activation could discriminate FMF patients from healthy donors (HD) and from patients with other inflammatory disorders (OID).

METHODS

Real-time pyroptosis and IL-1β secretion were monitored in response to UCN-01 in monocytes from FMF patients (n=67), HD (n=71) and OID patients (n=40). Sensitivity and specificity of the resulting diagnostic tests were determined by receiver operating characteristic curve analyses.

RESULTS

Inflammasome monitoring in response to UCN-01 discriminates FMF patients from other individuals. Pyroptosis assessment leads to a fast FMF diagnosis while combining pyroptosis and IL-1β dosage renders UCN-01-based assays highly sensitive and specific. UCN-01-triggered monocytes responses were influenced by MEFV gene dosage and MEFV mutations in a similar way as clinical phenotypes are.

CONCLUSIONS

UCN-01-based inflammasome assays could be used to rapidly diagnose FMF, with high sensitivity and specificity.

AA amyloidosis associated with Fabry disease

BACKGROUND

Fabry disease (FD) is the second most common lysosomal storage disorder, carrying a large morbidity and mortality. It has been recently reported that lysosomal storage disorders could cause inflammation and, subsequently, AA amyloidosis (AAA). Our aim was to describe AAA cases occurring in the course of FD.

PATIENTS AND METHODS

We described two patients displaying both AAA and FD and an additional case from the literature.

RESULTS

Three female patients originating from Europe (n = 2) and Algeria (n = 1) harboured heterozygous GLA mutations. The median age at AAA diagnosis was 61 years old. The diagnosis of Fabry was made before the diagnosis of AAA (n = 1) or concomitantly (n = 2). At AAA diagnosis, two patients displayed a nephrotic syndrome; all had inflammation.

CONCLUSION

Fabry disease can be associated with AAA, suggesting that an inflammatory component could exist in this genetic disease.

Prognostic Value of Hyponatremia During Acute Painful Episodes in Sickle Cell Disease

BACKGROUND

Low plasma sodium concentration has been recognized as a prognostic factor in several disorders but never evaluated in sickle cell disease. The present study evaluates its value at admission to predict a complication in adult patients with sickle cell disease hospitalized for an initially uncomplicated acute painful episode.

METHODS

The primary outcome of this retrospective study, performed between 2010 and 2015 in a French referral center for sickle cell disease, was a composite criterion including acute chest syndrome, intensive care unit transfer, red blood cell transfusion or inpatient death. Analyses were adjusted for age, sex, hemoglobin genotype and concentration, lactate dehydrogenase (LDH) concentration, and white blood cell count.

RESULTS

We included 1218 stays (406 patients). No inpatient death occurred during the study period. Hyponatremia (plasma sodium ≤135 mmol/L) at admission in the center was associated with the primary outcome (adjusted odds ratio [OR] 1.95, 95% confidence interval [CI] 1.3-2.91, P = 0.001), with acute chest syndrome (OR 1.95 [95% CI 1.2-3.17, P = 0.008]), and red blood cell transfusion (OR 2.71 [95% CI 1.58-4.65, P <0.001]) but not significantly with intensive care unit transfer (OR 1.83 [95% CI 0.94-3.79, P = 0.074]). Adjusted mean length of stay was longer by 1.1 days (95% CI 0.5-1.6, P <0.001) in patients with hyponatremia at admission.

CONCLUSIONS

Hyponatremia at admission in the medical department for an acute painful episode is a strong and independent prognostic factor of unfavorable outcome and, notably, acute chest syndrome. It could help targeting patients who may benefit from closer monitoring.