Hereditary Amyloidosis: Insights Into a Fibrinogen A Variant Protein.

Amyloidosis are a group of diseases in which soluble proteins aggregate and deposit in fibrillar conformation extracellularly in tissues. The effectiveness of therapeutic strategies depends on the specific protein involved, being crucial to accurately determine its nature. Moreover, following the diagnosis, the search for the mutation within relatives allows the clinical advice. Here we report the precise diagnosis and explored the possible reasons of the structural pathogenicity for a renal amyloidosis related to a fibrinogen Aα-chain variant. Whole-exome sequencing and GATK calling pipeline were leveraged to characterize the protein variant present in a patient with kidney failure. Bioinformatics strategies were applied to suggest potential explanations of the variants aggregation. Our pipeline allowed the identification of a single-point variant of fibrinogen Aα-chain, which opened the possibility of curative transplantation. In silico structural analysis suggested that the pathogenicity of the variant may be attributed to a heightened susceptibility to yield a peptide prone to deposit as an oligomer with a ß-sheet structure. Exploiting the comprehensive coverage of whole-genome sequencing, we managed to fill a vacant stage in the diagnosis of hereditary amyloidosis and to stimulate the advancement in biomedicine.

Aging Kidney Transplantation.

There are several immunological and non-immunological factors related to renal graft deterioration, and histological lesions such as interstitial fibrosis and tubular atrophy overlap with those observed in aging kidneys. Consequently, it has been proposed that kidney transplant senescence could contribute to graft loss. The process of cell senescence displays characteristics such as an increased expression of specific aging suppressor genes, shortened telomeres, mitochondrial changes, increased expression of negative regulators of the cell cycle, and immunological senescence. Additionally, tubular frailty characterizes the aged kidney, making it more susceptible to ischemia, reperfusion, toxic injury, and consequently, to inflammation. Moreover, renal tissue injury predisposes the older graft not only to progressive deterioration due to glomerular hyperfiltration, but also triggers acute rejection due to increased immunogenicity. In conclusion, renal graft senescence is a complex process, and its better understanding will help the nephrologist in its management in order to achieve a longer graft survival.

Renal Transplantation in Patients Older Than 60 Years With High Comorbidity. Is There a Survival Benefit? A Multicenter Study in Argentina.

BACKGROUND: The impact of renal transplantation (RT) in the elderly with many comorbid conditions is a matter of concern. The aim of our study was to assess the impact of RT on the survival of patients older than 60 years compared with those remaining on the waiting list (WL) according to their comorbidities. METHODS: In this multicentric observational retrospective cohort study, we included all patients older than 60 years old admitted on the WL from 01 January 2006 to 31 December 2016. The Charlson comorbidity index (CCI) score was calculated for each patient at inclusion on the WL. Kidney donor risk index was used to assess donor characteristics. RESULTS: One thousand and thirty-six patients were included on the WL of which 371 (36%) received an RT during a median follow-up period of 2.5 (1.4-4.1) years. Patient survival was higher after RT compared to patients remaining on the WL, 87%, 80%, and 72% versus 87%, 55%, and 30% at 1, 3, and 5 years, respectively. After RT survival at 5 years was 37% higher for patients with CCI ≥ 3, and 46% higher in those with CCI < 3, compared with patients remaining on the WL. On univariate and multivariate analysis, patient survival was independently associated with a CCI of ≥3 (hazard ratio 1.62; confidence interval 1.09-2.41; P < 0.02) and the use of calcineurin-based therapy maintenance therapy (hazard ratio 0.53; confidence interval 0.34-0.82; P < 0.004). CONCLUSIONS: Our study showed that RT improved survival in patients older than 60 years even those with high comorbidities. The survival after transplantation was also affected by comorbidities.