Background: Transthyretin amyloidosis cardiomyopathy (ATTR-CM) is an increasingly recognized cause of heart failure in older individuals. We sought to characterize the natural history of ATTR-CM and compare outcomes and quality of life among patients with acquired and hereditary forms of the disease. Methods: We studied 711 patients with wild-type ATTR-CM, 205 with hereditary ATTR-CM associated with the V122I variant (V122I-hATTR-CM), and 118 with non-V122I-hATTR-CM at the UK National Amyloidosis Center between 2000 and 2017. Patients underwent prospective protocolized evaluations comprising assessment of cardiac parameters, functional status by 6-minute walk test, quality of life according to the Kansas City Cardiomyopathy Questionnaire, and survival. Hospital service usage pre- and postdiagnosis was established using English central health records in a subset of patients. Results: There was substantial diagnostic delay, with patients using hospital services a median (interquartile range) of 17 (9–27) times during the 3 years before diagnosis, by which time quality of life was poor; diagnosis of wild-type ATTR-CM was delayed >4 years after presentation with cardiac symptoms in 42% of cases. Patients with V122I-hATTR-CM were more impaired functionally ( P <0.001) and had worse measures of cardiac disease ( P <0.001) at the time of diagnosis, a greater decline in quality of life, and poorer survival ( P <0.001) in comparison with the other subgroups. Conclusions: ATTR-CM is an inexorably progressive and eventually fatal cardiomyopathy associated with poor quality of life. Diagnosis is often delayed for many years after symptoms develop. Improved awareness and wider use of recently validated diagnostic imaging methods are urgently required for patients to benefit from recent therapeutic developments.

Wolbachia endosymbiotic bacteria have been implicated in the inflammatory pathogenesis of filariasis. Inflammation induced by Brugia malayi female worm extract (BMFE) is dependent on Toll-like receptors 2 and 6 (TLR2/6) with only a partial requirement for TLR1. Removal of Wolbachia, lipids, or proteins eliminates all inflammatory activity. Wolbachia bacteria contain the lipoprotein biosynthesis genes Ltg and LspA but not Lnt, suggesting Wolbachia proteins cannot be triacylated, accounting for recognition by TLR2/6. Lipoprotein databases revealed 3–11 potential lipoproteins from Wolbachia. Peptidoglycan-associated lipoprotein (PAL) and Type IV secretion system-VirB6 were consistently predicted, and B. malayi Wolbachia PAL (wBmPAL) was selected for functional characterization. Diacylated 20-mer peptides of wBmPAL (Diacyl Wolbachia lipopeptide (Diacyl WoLP)) showed a near identical TLR2/6 and TLR2/1 usage compared with BMFE and bound directly to TLR2. Diacyl WoLP induced systemic tumor necrosis factor-α and neutrophil-mediated keratitis in mice. Diacyl WoLP activated monocytes induce up-regulation of gp38 on human lymphatic endothelial cells and induced dendritic cell maturation and activation. Dendritic cells primed with BMFE generated a non-polarized Th1/Th2 CD4+ T cell profile, whereas priming with Wolbachia depleted extracts (following tetracycline treatment; BMFEtet) polarized to a Th2 profile that could be reversed by reconstitution with Diacyl WoLP. BMFE generated IgG1 and IgG2c antibody responses, whereas BMFEtet or inoculation of TLR2 or MyD88−/− mice produced defective IgG2c responses. Thus, in addition to innate inflammatory activation, Wolbachia lipoproteins drive interferon-γ-dependent CD4+ T cell polarization and antibody switching.

This article reports the largest series of patients with systemic AL amyloidosis to date treated with first-line bortezomib. With relatively mature follow-up, the data indicate the importance of a stringent dFLC response (difference in involved and uninvolved light chains) as a predictor of prolonged response.

Transthyretin amyloidosis (ATTR) is caused by deposition of either wild-type (ATTRwt) or variant (ATTRm) transthyretin. ATTRwt presents with restrictive cardiomyopathy, while ATTRm displays a range of organ involvement. This retrospective analysis includes all patients referred to a single UK center in the last 25 years for clinical and laboratory assessment of known or suspected amyloidosis who underwent TTR gene sequencing. A total of 4459 patients were included in this study; 37% had final diagnosis of ATTR amyloidosis; 27% light chain amyloidosis; 0.7% other types of amyloidosis; 21.3% had no amyloid and 14% had no data. TTR variants were found in 770 (17%) cases; the most prevalent were p.V142I, p.T80A, and p.V50M identified in 42, 25, and 16%, respectively. The median age at referral in each group was: 76 (range 47-93), 66 (40-81), and 45 years (21-86), respectively. Overall 42 rare or novel variants were identified. Forty-two percent patients with ATTRm died at a median age of 73 years (33-89) with a median survival from diagnosis of 50 months. ATTRwt was the final diagnosis in 20% of patients undergoing genetic testing. Our findings of TTR variants in 17% of screened patients highlight the need for routine genetic testing in the evaluation of suspected ATTR amyloidosis.