Clinical characteristics and SAP scintigraphic findings in 10 patients with AGel amyloidosis.

The clinical features of hereditary gelsolin (AGel) amyloidosis include corneal lattice dystrophy, distal sensorimotor, cranial neuropathy and cutis laxa. To date, four mutations of the gelsolin (GSN) gene encoding the following variants have been identified as the cause of this malady; p.D214N, p.D214Y, p.G194R and p.N211K (this nomenclature includes the 27-residue signal peptide). Interestingly, the latter two variants are associated exclusively with a renal amyloidosis phenotype. Here we report the clinical features in 10 patients with AGel amyloidosis associated with the p.D214N mutation, all of whom underwent whole body (123)I-SAP scintigraphy and were followed up in a single UK Centre for a prolonged period. Two patients, from the same kindred presented with proteinuria; eight subjects had a characteristic AGel amyloidosis phenotype including cranial neuropathy and/or corneal lattice dystrophy. (123)I-SAP scintigraphy revealed substantial renal amyloid deposits in all 10 patients, including those with preserved renal function, and usually without tracer uptake into other visceral organs. (123)I-SAP scintigraphy is a non-invasive technique that aids early diagnosis of patients with this rare disease, especially those who lack a family history and/or present with an unusual clinical phenotype.

AA amyloidosis complicating the hereditary periodic fever syndromes.

OBJECTIVE: AA amyloidosis is a life-threatening complication of the hereditary periodic fever syndromes (HPFS), which are otherwise often compatible with normal life expectancy. This study was undertaken to determine the characteristics, presentation, natural history, and response to treatment in 46 patients who had been referred for evaluation at the UK National Amyloidosis Centre. METHODS: Disease activity was monitored by serial measurement of serum amyloid A. Renal function was assessed by measurement of serum creatinine and albumin levels, the estimated glomerular filtration rate, and proteinuria from 24-hour urine collections. The amyloid load was measured by serum amyloid P scintigraphy. RESULTS: Twenty-four patients had familial Mediterranean fever, 12 patients had tumor necrosis factor receptor-associated periodic syndrome, 6 patients had cryopyrin-associated periodic syndromes, and 4 patients had mevalonate kinase deficiency. The median age at onset of HPFS was 5 years; median age at presentation with AA amyloidosis was 38 years. Diagnosis of an HPFS had not been considered prior to presentation with AA amyloidosis in 23 patients (50%). Eleven patients (24%) had end-stage renal failure (ESRF) at presentation; of these, 3 had received transplants prior to referral. A further 13 patients developed ESRF over the followup period, with 10 undergoing renal transplantation. The median time to progression to ESRF from onset of AA amyloidosis was 3.3 years (interquartile range [IQR] 2-8), with a median time to transplant of 4 years (IQR 3-6). Eleven patients (24%) died. The median survival in the entire cohort was 19 years from diagnosis of AA amyloidosis. Of the 37 patients who were treated successfully, or in whom at least partial suppression of the underlying HPFS was achieved, 17 (46%) showed amyloid regression, 14 (38%) showed a stable amyloid load, and 2 (5%) showed increased amyloid deposition over the followup period. CONCLUSION: AA amyloidosis remains a challenging and serious late complication of HPFS; however, outcomes are excellent when HPFS is diagnosed early enough to allow effective treatment, thus preventing or retarding further amyloid deposition and organ damage.

Phenotype, genotype, and sustained response to anakinra in 22 patients with autoinflammatory disease associated with CIAS-1/NALP3 mutations.

OBJECTIVE: To characterize the multisystem chronic inflammatory phenotype, dermatopathologic features, and response to therapy with interleukin 1 receptor antagonist (anakinra) in patients with mutations in the CIAS-1/NALP3 gene. DESIGN: Retrospective review of medical records and evaluation of histologic findings. SETTING: The National Amyloidosis Centre, London, and a tertiary referral clinic for urticaria. PATIENTS: Twenty-two individuals from 13 families with autoinflammatory disease associated with CIAS-1/NALP3 mutations. MAIN OUTCOME MEASURES: Phenotype, genotype, skin histologic findings, and response to treatment with anakinra. RESULTS: Five heterozygous missense mutations were identified in CIAS-1/NALP3. Skin histologic findings revealed marked vascular dilatation and neutrophilic infiltration involving small vessels and eccrine glands. Serologic evidence of intense inflammation was present in untreated patients, with median serum amyloid A protein and C-reactive protein levels of 141 and 38 mg/L, respectively. Fifteen patients received anakinra for up to 39 months, all of whom achieved serologic remission and complete resolution of fever, rash, conjunctivitis, and rheumatic symptoms, without any adverse effects. Six patients had AA (reactive systemic) amyloidosis, 2 of whom died of renal failure complications before interleukin 1-inhibiting therapy was available; 1 patient underwent renal transplantation and remains clinically well taking anakinra, and in the remaining 3 patients, anakinra therapy resulted in remission of their nephrotic syndrome. CONCLUSIONS: Anakinra therapy was well tolerated and has sustained efficacy on dermatologic and rheumatic manifestations in these patients with CIAS-1/NALP3 mutations. This treatment also resulted in resolution of AA amyloidosis-associated nephrotic syndrome in all affected patients.

AA amyloidosis complicating hyperimmunoglobulinemia D with periodic fever syndrome: a report of two cases.

AA amyloidosis is the most serious potential complication of the inherited autoinflammatory syndromes and frequently results in end-stage renal failure. Although this complication is well recognized in familial Mediterranean fever, tumor necrosis factor receptor-associated periodic syndrome, and Muckle-Wells syndrome, there is only 1 previous published report of its occurrence in hyperimmunoglobulinemia D with periodic fever syndrome (HIDS). We report 2 further cases of patients with AA amyloidosis in HIDS, both of whom developed dialysis-dependent renal failure, and we describe the outcome of the first renal transplant in this setting.

Hereditary amyloidosis in early childhood associated with a novel insertion-deletion (indel) in the fibrinogen Aalpha chain gene.

BACKGROUND: Systemic amyloidosis occurring in early childhood is extremely rare, and is usually of AA type complicating chronic inflammatory diseases. We report the molecular basis of amyloidosis in a Korean girl who presented at 7 years of age with asymptomatic proteinuria and developed amyloid hepatomegaly and end-stage renal failure within 2 years. METHODS: Renal biopsy showed enlarged glomeruli virtually replaced by amyloid, but without interstitial or vascular involvement. The histologic appearance was identical to that seen in patients with hereditary fibrinogen Aalpha chain Glu526Val amyloidosis, and the amyloid deposits stained specifically with antibodies to fibrinogen. Mutations were sought in the genes of the amyloidogenic proteins, transthyretin, apolipoprotein AI, lysozyme and fibrinogen Aalpha chain genes by polymerase chain reaction (PCR) and sequencing. RESULTS: A unique frameshift insertion-deletion (indel) mutation was identified in one allele of her fibrinogen Aalpha chain gene, which encodes a partly novel peptide and a premature stop signal, similar to the two previously reported amyloidogenic point deletions at codons 522 and 524 in this molecule. The mutation was absent in samples verified to be from her parents, indicating that it had occurred de novo. CONCLUSION: This is the first description of hereditary fibrinogen Aalpha chain amyloidosis in an Asian individual, and the distinctive renal histology offered a strong clue to the diagnosis. The disease is potentially curable by combined hepatorenal transplantation.

Familial amyloidotic polyneuropathy with severe renal involvement in association with transthyretin Gly47Glu in Dutch, British and American-Finnish families.

Familial amyloidotic polyneuropathy (FAP) is an autosomal dominant disorder associated with more than 80 different transthyretin (TTR) mutations. The clinical features of FAP are broad and variable, but knowledge of the pattern and natural history of disease associated with particular mutations nevertheless offers the best guidance for management of individual patients, including the role and timming of treatment by orthotopic liver transplantation. FAP in association with TTR Gly47Glu has been described previously in an Italian kindred, and we report here its phenotype in 7 additional patients from Dutch, British, and American (Finnish) families. Characteristic clinical features included amyloid cardiomyopathy and autonomic failure but, unusually, moderate to severe renal failure was present in more than half of the cases. Only four patients were deemed to be sufficiently fit to undergo orthotopic liver transplantation, and clinical deterioration was generally rapid. These observations support early intervention with orthotopic liver transplantation in patients with FAP associated with TTR Gly47Glu.

Autoimmunity and glomerulonephritis in mice with targeted deletion of the serum amyloid P component gene: SAP deficiency or strain combination?

Human serum amyloid P component (SAP) binds avidly to DNA, chromatin and apoptotic cells in vitro and in vivo. 129/Sv x C57BL/6 mice with targeted deletion of the SAP gene spontaneously develop antinuclear autoantibodies and immune complex glomerulonephritis. SAP-deficient animals, created by backcrossing the 129/Sv SAP gene deletion into pure line C57BL/6 mice and studied here for the first time, also spontaneously developed broad spectrum antinuclear autoimmunity and proliferative immune complex glomerulonephritis but without proteinuria, renal failure, or increased morbidity or mortality. Mice hemizygous for the SAP gene deletion had an intermediate autoimmune phenotype. Injected apoptotic cells and isolated chromatin were more immunogenic in SAP(-/-) mice than in wild-type mice. In contrast, SAP-deficient pure line 129/Sv mice did not produce significant autoantibodies either spontaneously or when immunized with extrinsic chromatin or apoptotic cells, indicating that loss of tolerance is markedly strain dependent. However, SAP deficiency in C57BL/6 mice only marginally affected plasma clearance of exogenous chromatin and had no effect on distribution of exogenous nucleosomes between the liver and kidneys, which were the only tissue sites of catabolism. Furthermore, transgenic expression of human SAP in the C57BL/6 SAP knockout mice did not abrogate the autoimmune phenotype. This may reflect the different binding affinities of mouse and human SAP for nuclear autoantigens and/or the heterologous nature of transgenic human SAP in the mouse. Alternatively, the autoimmunity may be independent of SAP deficiency and caused by expression of 129/Sv chromosome 1 genes in the C57BL/6 background.

Heterogeneity among patients with tumor necrosis factor receptor-associated periodic syndrome phenotypes.

OBJECTIVE: To investigate the prevalence of tumor necrosis factor receptor-associated periodic syndrome (TRAPS) among outpatients presenting with recurrent fevers and clinical features consistent with TRAPS. METHODS: Mutational screening was performed in affected members of 18 families in which multiple members had symptoms compatible with TRAPS and in 176 consecutive subjects with sporadic (nonfamilial) "TRAPS-like" symptoms. Plasma concentrations of soluble tumor necrosis factor receptor superfamily 1A (sTNFRSF1A) were measured, and fluorescence-activated cell sorter analysis was used to measure TNFRSF1A shedding from monocytes. RESULTS: Eight novel and 3 previously reported TNFRSF1A missense mutations were identified, including an amino acid deletion (Delta D42) in a Northern Irish family and a C70S mutation in a Japanese family, both reported for the first time. Only 3 TNFRSF1A variants were found in patients with sporadic TRAPS (4 of 176 patients). Evidence for nonallelic heterogeneity in TRAPS-like conditions was found: 3 members of the "prototype familial Hibernian fever" family did not possess C33Y, present in 9 other affected members. Plasma sTNFRSF1A levels were low in TRAPS patients in whom renal amyloidosis had not developed, but also in mutation-negative symptomatic subjects in 4 families, and in 14 patients (8%) with sporadic TRAPS. Reduced shedding of TNFRSF1A from monocytes was demonstrated in vitro in patients with the T50M and T50K variants, but not in those with other variants. CONCLUSION: The presence of TNFRSF1A shedding defects and low sTNFRSF1A levels in 3 families without a TNFRSF1A mutation indicates that the genetic basis among patients with "TRAPS-like" features is heterogeneous. TNFRSF1A mutations are not commonly associated with nonfamilial recurrent fevers of unknown etiology.

MHC typing in variant Creutzfeldt-Jakob disease.

Identification of factors that cause susceptibility to, and clinical expression of, variant Creutzfeldt-Jakob disease (vCJD) is essential for future management of the disease. We established MHC genotypes of 76 individuals with vCJD and 131 controls, and analysed MHC phenotypes in relation to age of onset of vCJD and its duration from presentation to death. There were no significant differences between vCJD and control populations in frequencies of any MHC types, nor were there associations between MHC type and age of onset or duration of vCJD disease. Our results do not support the idea of an association between MHC types and either susceptibility to, or expression of, vCJD.

Association of mutations in the NALP3/CIAS1/PYPAF1 gene with a broad phenotype including recurrent fever, cold sensitivity, sensorineural deafness, and AA amyloidosis.

OBJECTIVE: Familial cold urticaria (FCU) and Muckle-Wells syndrome (MWS) are dominantly inherited autoinflammatory disorders that cause rashes, fever, arthralgia, and in some subjects, AA amyloidosis, and have been mapped to chromosome 1q44. Sensorineural deafness in MWS, and provocation of symptoms by cold in FCU, are distinctive features. This study was undertaken to characterize the genetic basis of FCU, MWS, and an overlapping disorder in French Canadian, British, and Indian families, respectively. METHODS: Mutations in the candidate gene NALP3, which has also been named CIAS1 and PYPAF1, were sought in the study families, in a British/Spanish patient with apparent sporadic MWS, and in matched population controls. Identified variants were sought in 50 European subjects with uncharacterized, apparently sporadic periodic fever syndromes, 48 subjects with rheumatoid arthritis (RA), and 19 subjects with juvenile idiopathic arthritis (JIA). RESULTS: Point mutations, encoding putative protein variants R262W and L307P, were present in all affected members of the Indian and French Canadian families, respectively, but not in controls. The R262W variant was also present in the subject with sporadic MWS. The V200M variant was present in all affected members of the British family with MWS, in 2 of the 50 subjects with uncharacterized periodic fevers, and in 1 of 130 Caucasian and 2 of 48 Indian healthy controls. No mutations were identified among the subjects with RA or JIA. CONCLUSION: These findings confirm that mutations in the NALP3/CIAS1/PYPAF1 gene are associated with FCU and MWS, and that disease severity and clinical features may differ substantially within and between families. Analysis of this gene will improve classification of patients with inherited or apparently sporadic periodic fever syndromes.

Misdiagnosis of hereditary amyloidosis as AL (primary) amyloidosis.

BACKGROUND: Hereditary, autosomal dominant amyloidosis, caused by mutations in the genes encoding transthyretin, fibrinogen A alpha-chain, lysozyme, or apolipoprotein A-I, is thought to be extremely rare and is not routinely included in the differential diagnosis of systemic amyloidosis unless there is a family history. METHODS: We studied 350 patients with systemic amyloidosis, in whom a diagnosis of the light-chain (AL) type of the disorder had been suggested by clinical and laboratory findings and by the absence of a family history, to assess whether they had amyloidogenic mutations. RESULTS: Amyloidogenic mutations were present in 34 of the 350 patients (9.7 percent), most often in the genes encoding fibrinogen A alpha-chain (18 patients) and transthyretin (13 patients). In all 34 of these patients, the diagnosis of hereditary amyloidosis was confirmed by additional investigations. A low-grade monoclonal gammopathy was detected in 8 of the 34 patients (24 percent). CONCLUSIONS: A genetic cause should be sought in all patients with amyloidosis that is not the reactive systemic amyloid A type and in whom confirmation of the AL type cannot be obtained.