Search

Purpose: A new syndrome with hypotonia, intellectual disability, and eye abnormalities (HIDEA) was previously described in a large consanguineous family. Linkage analysis identified the recessive disease locus, and genome sequencing yielded three candidate genes with potentially pathogenic biallelic variants: transketolase (TKT), transmembrane prolyl 4-hydroxylase (P4HTM), and ubiquitin specific peptidase 4 (USP4). However, the causative gene remained elusive., Methods: International collaboration and exome sequencing were used to identify new patients with HIDEA and biallelic, potentially pathogenic, P4HTM variants. Segregation analysis was performed using Sanger sequencing. P4H-TM wild-type and variant constructs without the transmembrane region were overexpressed in insect cells and analyzed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western blot., Results: Five different homozygous or compound heterozygous pathogenic P4HTM gene variants were identified in six new and six previously published patients presenting with HIDEA. Hypoventilation, obstructive and central sleep apnea, and dysautonomia were identified as novel features associated with the phenotype. Characterization of three of the P4H-TM variants demonstrated yielding insoluble protein products and, thus, loss-of-function., Conclusions: Biallelic loss-of-function P4HTM variants were shown to cause HIDEA syndrome. Our findings enable diagnosis of the condition, and highlight the importance of assessing the need for noninvasive ventilatory support in patients.

Objectives: This study sought to compare techniques evaluating cardiac dysautonomia and predicting the risk of death of patients with hereditary transthyretin amyloidosis (mATTR) after liver transplantation (LT)., Background: mATTR is a multisystemic disease involving mainly the heart and the peripheral nervous system. LT is the reference treatment, and pre-operative detection of high-risk patients is critical. Cardiovascular dysautonomia is commonly encountered in ATTR and may affect patient outcome, although it is not known yet which technique should be used in the field to evaluate it., Methods: In a series of 215 consecutive mATTR patients who underwent LT, cardiac dysautonomia was assessed by a dedicated clinical score, time-domain heart rate variability, 123 -meta-iodobenzylguanidine heart/mediastinum ( 123 -MIBG H/M) ratio on scintigraphy, and heart rate response to atropine (HRRA)., Results: Patient median age was 43 years, 62% were male and 69% carried the Val30Met mutation. Cardiac dysautonomia was documented by at least 1 technique for all patients but 6 (97%). In univariate analysis, clinical score, 123 -MIBG H/M ratio and HRRA were associated with mortality but not heart rate variability. The 123 -MIBG H/M ratio and HRRA had greater area under the curve (AUC) of receiver-operating characteristic curves than clinical score and heart rate variability (AUC: 0.787, 0.748, 0.656, and 0.523, respectively). Multivariate score models were then built using the following variables: New York Heart Association functional class, interventricular septum thickness, and either 123- MIBG H/M ratio (S MIBG ) or HRRA (S atropine ). AUC of S MIBG and S atropine were greater than AUC of univariate models, although nonsignificantly (AUC: 0.798 and 0.799, respectively). Predictive powers of S MIBG , S atropine , and a reference clinical model (AUC: 0.785) were similar., Conclusions: Evaluation of cardiac dysautonomia is a valuable addition for predicting survival of mATTR patients following LT. Among the different techniques that evaluate cardiac dysautonomia, 123 -MIBG scintigraphy and heart rate response to atropine had better prognostic accuracy. Multivariate models did not improve significantly prediction of outcome., (Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

SPG3A, which is the second most common type of autosomal dominant hereditary spastic paraplegia (HSP), is caused by mutations in the atlastin GTPase 1 gene, ATL1. We report a case of a patient who presented as dysautonomia and had a novel splicing mutation c.35-3C>T in exon 2 of the ATL1. Orthostatic intolerance, urinary symptoms, hyperreflexia in the biceps and knee jerk, and decreased proprioception in both limbs were observed on neurological examinations. We tested the autonomic function and performed genetic tests for the SPG4 and SPG3A forms of HSP. This case is a genetically confirmed HSP with a novel mutation in SPG3A, and extends the phenotype of SPG3A., (Copyright © 2014 Elsevier B.V. All rights reserved.)