The lung in amyloidosis

Amyloidosis is a disorder caused by misfolding of autologous protein and its extracellular deposition as fibrils, resulting in vital organ dysfunction and eventually death. Pulmonary amyloidosis may be localised or part of systemic amyloidosis.Pulmonary interstitial amyloidosis is symptomatic only if the amyloid deposits severely affect gas exchange alveolar structure, thus resulting in serious respiratory impairment. Localised parenchymal involvement may be present as nodular amyloidosis or as amyloid deposits associated with localised lymphomas. Finally, tracheobronchial amyloidosis, which is usually not associated with evident clonal proliferation, may result in airway stenosis.Because the treatment options for amyloidosis are dependent on the fibril protein type, the workup of all new cases should include accurate determination of the amyloid protein. Most cases are asymptomatic and need only a careful follow-up. Diffuse alveolar-septal amyloidosis is treated according to the underlying systemic amyloidosis. Nodular pulmonary amyloidosis is usually localised, conservative excision is usually curative and the long-term prognosis is excellent. Tracheobronchial amyloidosis is usually treated with bronchoscopic interventions or external beam radiation therapy

Prospective urinary albumin/creatinine ratio for diagnosis, staging, and organ response assessment in renal AL amyloidosis: results from a large cohort of patients

Abstract Objectives Quantification of 24 h-proteinuria is the gold standard for diagnosing, staging, and monitoring of patients with renal AL amyloidosis. However, 24 h-urine collection is cumbersome and may result in preanalytical error. In this prospective study, we investigated the role of urinary albumin/creatinine ratio (UACR) (cut-off: 300 mg/g) identifying renal involvement, evaluated a UACR-based staging system (UACR cut-off: 3,600 mg/g) and assessed whether UACR response (UACR decrease >30% without worsening in eGFR >25%) predicts renal outcome in 531 patients with newly-diagnosed AL amyloidosis. Methods From October 2013 paired 24 h-proteinuria and UACR (on first morning void) were measured in all newly-diagnosed patients with AL amyloidosis. Correlation between 24 h-proteinuria and UACR at baseline was assessed by Pearson's r test. Impact of UACR response on renal outcome was assessed in randomly created testing (n=354) and validation (n=177) cohorts. Results A strong linear correlation was found between 24 h-proteinuria and UACR at baseline (r=0.90; p<0.001). After a median follow-up of 31 months, 57 (11%) patients required dialysis. A UACR-based renal staging system identified three stages with significantly higher dialysis rate at 36 months comparing stage I with stage II and stage II with stage III. Achieving a renal response, according to a UACR-based criterion, resulted in lower dialysis rate in both testing and validation cohorts. Conclusions UACR is a reliable marker for diagnosis, prognosis, and organ response assessment in renal AL amyloidosis and can reliably replace 24 h-proteinuria in clinical trials and individual patients' management

Minimal residual disease negativity by next-generation flow cytometry is associated with improved organ response in AL amyloidosis

© The Author(s) 2021.Light chain (AL) amyloidosis is caused by a small B-cell clone producing light chains that form amyloid deposits and cause organ dysfunction. Chemotherapy aims at suppressing the production of the toxic light chain (LC) and restore organ function. However, even complete hematologic response (CR), defined as negative serum and urine immunofixation and normalized free LC ratio, does not always translate into organ response. Next-generation flow (NGF) cytometry is used to detect minimal residual disease (MRD) in multiple myeloma. We evaluated MRD by NGF in 92 AL amyloidosis patients in CR. Fifty-four percent had persistent MRD (median 0.03% abnormal plasma cells). There were no differences in baseline clinical variables in patients with or without detectable MRD. Undetectable MRD was associated with higher rates of renal (90% vs 62%, p = 0.006) and cardiac response (95% vs 75%, p = 0.023). Hematologic progression was more frequent in MRD positive (0 vs 25% at 1 year, p = 0.001). Altogether, NGF can detect MRD in approximately half the AL amyloidosis patients in CR, and persistent MRD can explain persistent organ dysfunction. Thus, this study supports testing MRD in CR patients, especially if not accompanied by organ response. In case MRD persists, further treatment could be considered, carefully balancing residual organ damage, patient frailty, and possible toxicity.This study was supported by a grant from CARIPLO “Molecular mechanisms of Ig toxicity in age-related plasma cell dyscrasias no. 2015-0591”, by a grant from the Black Swan Research Initiative from the International Myeloma Foundation “Automated multidimensional flow cytometry for high-sensitive screening and to monitor response in AL amyloidosis”, by a grant from CARIPLO “Structure–function relation of amyloid: understanding the molecular bases of protein misfolding diseases to design new treatments no. 2013-0964”, by a grant from the Amyloidosis Foundation “Investigating new therapies to treat AL amyloidosis”, and by a grant from Cancer Research UK, FCAECC and AIRC under the Accelerator Award 2017 Program “Early detection and intervention: understanding the mechanisms of transformation and hidden resistance of incurable hematological malignancies”, by a grant from CARIPLO “Harnessing the plasma cell secretory capacity against systemic light chain amyloidosis” (no. 2018-0257), by a grant from the Italian Ministry of Health “Towards effective, patient-tailored anti-plasma cell therapies in AL amyloidosis: predicting drug response and overcoming drug resistance” (GR-2018-12368387). This study has also supported the Centro de Investigación Biomédica en Red—Área de Oncología—del Instituto de Salud Carlos III (CIBERONC; CB16/12/00369, CB16/12/00400, and CB16/12/00489) and the Instituto de Salud Carlos III/Subdirección General de Investigación Sanitaria (FIS No. PI13/02196). G.P. is supported in part by the Bart Barlogie Young Investigator Award from the International Myeloma Society (IMS). P.M. is supported in part by a fellowship grant form Collegio Ghislieri (Pavia). We acknowledge the study coordinator and data manager Anna Carnevale Baraglia

Consistent patterns of common species across tropical tree communities

Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.Publisher PDFPeer reviewe

The lung in amyloidosis

Amyloidosis is a disorder caused by misfolding of autologous protein and its extracellular deposition as fibrils, resulting in vital organ dysfunction and eventually death. Pulmonary amyloidosis may be localised or part of systemic amyloidosis. Pulmonary interstitial amyloidosis is symptomatic only if the amyloid deposits severely affect gas exchange alveolar structure, thus resulting in serious respiratory impairment. Localised parenchymal involvement may be present as nodular amyloidosis or as amyloid deposits associated with localised lymphomas. Finally, tracheobronchial amyloidosis, which is usually not associated with evident clonal proliferation, may result in airway stenosis. Because the treatment options for amyloidosis are dependent on the fibril protein type, the workup of all new cases should include accurate determination of the amyloid protein. Most cases are asymptomatic and need only a careful follow-up. Diffuse alveolar-septal amyloidosis is treated according to the underlying systemic amyloidosis. Nodular pulmonary amyloidosis is usually localised, conservative excision is usually curative and the long-term prognosis is excellent. Tracheobronchial amyloidosis is usually treated with bronchoscopic interventions or external beam radiation therapy

Patients with light-chain amyloidosis and low free light-chain burden have distinct clinical features and outcome

The validated criteria of hematologic response in light-chain (AL) amyloidosis are based on the measurement of circulating free light chains (FLCs). Patients with a difference between involved and uninvolved FLC (dFLC) <50 mg/L cannot be assessed for response and are excluded from clinical trials. We compared the clinical characteristics and outcome of 203 newly diagnosed patients with dFLC <50 mg/L (low dFLC) with 866 patients with measurable dFLC (high dFLC) evaluated between 2004 and 2015. Heart involvement was significantly less common and less advanced in the low-dFLC group (43% vs 83% and Mayo stage III 45% vs 15%, bothP< .001), whereas renal involvement was more frequent (77% vs 63%,P< .001) and more severe (renal stage III 26% vs 18%,P= .001). Overall survival (OS) was significantly better in the low-dFLC group (median 117 vs 21 months,P< .001), whereas no difference was seen in renal survival (RS). Within each Mayo stage, patients with low dFLC had a longer survival. In the low-dFLC group, complete response was associated with a significant advantage in OS (median not reached vs 117 months,P= .005) and with a better RS. A reduction in dFLC after therapy of <10 mg/L was associated with a better OS and RS in patients with at least a dFLC >20 mg/L baseline. Nineteen percent of newly diagnosed patients with AL amyloidosis have low dFLC and had a better outcome. Hematologic response assessed with adapted criteria predicts OS and RS in these patients, who can thus be assessed for response and included in clinical trials with appropriate stratification