Dataset Information

Atypical haemolytic uraemic syndrome associated with a hybrid complement gene.

ABSTRACT: BACKGROUND: Sequence analysis of the regulators of complement activation (RCA) cluster of genes at chromosome position 1q32 shows evidence of several large genomic duplications. These duplications have resulted in a high degree of sequence identity between the gene for factor H (CFH) and the genes for the five factor H-related proteins (CFHL1-5; aliases CFHR1-5). CFH mutations have been described in association with atypical haemolytic uraemic syndrome (aHUS). The majority of the mutations are missense changes that cluster in the C-terminal region and impair the ability of factor H to regulate surface-bound C3b. Some have arisen as a result of gene conversion between CFH and CFHL1. In this study we tested the hypothesis that nonallelic homologous recombination between low-copy repeats in the RCA cluster could result in the formation of a hybrid CFH/CFHL1 gene that predisposes to the development of aHUS. METHODS AND FINDINGS: In a family with many cases of aHUS that segregate with the RCA cluster we used cDNA analysis, gene sequencing, and Southern blotting to show that affected individuals carry a heterozygous CFH/CFHL1 hybrid gene in which exons 1-21 are derived from CFH and exons 22/23 from CFHL1. This hybrid encodes a protein product identical to a functionally significant CFH mutant (c.3572C>T, S1191L and c.3590T>C, V1197A) that has been previously described in association with aHUS. CONCLUSIONS: CFH mutation screening is recommended in all aHUS patients prior to renal transplantation because of the high risk of disease recurrence post-transplant in those known to have a CFH mutation. Because of our finding it will be necessary to implement additional screening strategies that will detect a hybrid CFH/CFHL1 gene.

SUBMITTER: Venables JP

PROVIDER: S-EPMC1626556 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Atypical haemolytic uraemic syndrome associated with a hybrid complement gene.

Venables Julian P JP Strain Lisa L Routledge Danny D Bourn David D Powell Helen M HM Warwicker Paul P Diaz-Torres Martha L ML Sampson Anne A Mead Paul P Webb Michelle M Pirson Yves Y Jackson Michael S MS Hughes Anne A Wood Katrina M KM Goodship Judith A JA Goodship Timothy H J TH

PLoS medicine 20061001 10

<h4>Background</h4>Sequence analysis of the regulators of complement activation (RCA) cluster of genes at chromosome position 1q32 shows evidence of several large genomic duplications. These duplications have resulted in a high degree of sequence identity between the gene for factor H (CFH) and the genes for the five factor H-related proteins (CFHL1-5; aliases CFHR1-5). CFH mutations have been described in association with atypical haemolytic uraemic syndrome (aHUS). The majority of the mutation ...[more]

PMID: 17076561

Similar Datasets

Project description:BackgroundAtypical haemolytic uraemic syndrome (aHUS) is a rare, potentially life-threatening condition caused by dysregulation of the complement pathway. Eculizumab is currently the only approved treatment for this disorder.ObjectiveOur objective was to investigate the impact of early administration of eculizumab on inpatient resource use and hospitalisation costs in 222 patients with aHUS.MethodsWe conducted a retrospective analysis of the Premier Perspective® Hospital Database, including patients with a diagnosis of aHUS and evidence of eculizumab use for aHUS. Early initiation was defined as having received eculizumab within 7 days of admission, with late initiation defined as starting eculizumab on day 8 or later. This date represents the average time required to obtain a specific diagnostic test to discriminate aHUS from a similar haemolytic syndrome that requires a different treatment. Outcome measures were time from first eculizumab initiation to discharge, discharge status or death, days spent in the intensive care unit (ICU), readmission indicators, dialysis indicators, and total hospital costs. Time from first eculizumab initiation to discharge was analysed using a generalised linear model with a log link and an assumed underlying negative binomial distribution. Logistic regression models were used to test the statistical significance of early versus late initiation as a predictor of the occurrence of readmissions, dialysis, and death. Total hospital costs were analysed using a generalised linear model with a log link and an assumed underlying gamma distribution.ResultsBefore modelling, total length of stay and ICU duration were significantly longer for late initiators than for early initiators, and significantly more late initiators were readmitted within 90 days. Late initiation was associated with significantly higher hospital costs than early initiation. After multivariable analysis, late initiators were 3.2 times more likely to require dialysis. However, there was no significant association between early initiation and time to discharge, readmission, or death for any definition or early initiation after multivariable analysis. Estimated total hospital costs (year 2017 values) were $US103,557 in late initiators and $US85,776 in early initiators (p = 0.0024).ConclusionInitiation of eculizumab within 7 days of hospitalisation is associated with lower dialysis rates, less time in ICU, less plasmapheresis, and lower hospitalisation costs compared with late initiation.

Dataset Information

Atypical haemolytic uraemic syndrome associated with a hybrid complement gene.

Publications

Atypical haemolytic uraemic syndrome associated with a hybrid complement gene.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets