Methodology for Generating Datasets with Characteristic Diagnostic Parameters of Rare Diseases Using the Example of Pompe Disease, Gaucher Disease and Smith-Lemli-Opitz Syndrome

BackgroundFinding a diagnosis for rare diseases is a challenge for patients and those treating them. Establishing a uniform methodology for specifying the symptoms of a patient seems useful. This, as well as a database with clinical parameters reported in patients already diagnosed with the corresponding disease or that have led to the diagnosis, would facilitate the global data exchange between specialists and subsequently diagnosis. The aim of this work is to develop standardized data sets with the most frequent symptoms exemplarily for the three rare diseases late-onset Pompe disease, Gaucher disease Type I and Smith-Lemli-Opitz syndrome (SLOS).Methods and resultsA systematic literature review of characteristic symptoms and diagnostic criteria was performed for each of the three disorders. These parameters were converted into vocabulary standardized by The Human Phenotype Ontology (HPO), so-called HPO terms. Subsequently, a retrospective analysis of the patient files of 23 late-onset Pompe disease patients, 21 Gaucher disease Type I patients and 25 SLOS patients was carried out together with the University Children's Hospital Magdeburg and the Center of excellence for Rare Metabolic Diseases at the Charité Berlin. Features present in ≥ 40 % of the cohort and collected simultaneously in a certain minimum number of patients were filtered out. The analysis resulted in data sets with 20 diagnostic parameters for late-onset Pompe disease, 16 features for Gaucher disease Type I and 17 parameters for SLOS. After the statistical evaluation, the results were discussed comparatively with similar studies exemplarily for SLOS.ConclusionThe developed datasets for the three diseases provide a good basis for expansion with further patient examples and for extending the methodology to other diseases with the aim of improving the diagnostic pathway and thus the health care of patients with rare diseases.

A de novo Variant of ASXL1 Is Associated With an Atypical Phenotype of Bohring-Opitz Syndrome: Case Report and Literature Review

Bohring-Opitz syndrome (BOS) is a rare genetic disease first reported by Bohring et al. in 1999. With the recent development of exome sequencing (ES), de novo truncating mutations in the additional sex-combs-like 1 (ASXL1) gene have been causally implicated in BOS. Herein, we describe a 7-month-old girl with intrauterine growth restriction, severe pulmonary infection, seizures, and craniofacial abnormalities (microcephaly, micro/retrognathia, hypertelorism, depressed nasal bridge, low-set ears and hypertrichosis) at birth. At a later stage, the patient developed global developmental delay. We performed ES and identified a de novo heterozygous mutation in ASXL1, namely, c.1210C>T/p.R404*. However, this case did not have trigonocephaly, facial hemangioma, prominent eyes, myopia, BOS posture, or brain abnormalities (enlarged subarachnoid spaces, agenesis of the corpus callosum, moderately enlarged cerebral ventricles, or prominent frontal subarachnoid spaces), which are common characteristics in most patients with BOS-harboring ASXL1 mutations. These new data expand the phenotype of BOS driven by ASXL1 and may assist in more accurately delineating the phenotypes caused by variants of this gene.

Biochemical and Clinical Effects of Vitamin E Supplementation in Hungarian Smith-Lemli-Opitz Syndrome Patients

Smith-Lemli-Opitz syndrome (SLOS) is a severe monogenic disorder resulting in low cholesterol and high 7-dehydrocholesterol (7-DHC) levels. 7-DHC-derived oxysterols likely contribute to disease pathophysiology, and thus antioxidant treatment might be beneficial because of high oxidative stress. In a three-year prospective study, we investigated the effects of vitamin E supplementation in six SLOS patients already receiving dietary cholesterol treatment. Plasma vitamin A and E concentrations were determined by the high-performance liquid chromatography (HPLC) method. At baseline, plasma 7-DHC, 8-dehydrocholesterol (8-DHC) and cholesterol levels were determined by liquid chromatography–tandem mass spectrometry (LC-MS/MS) method. The clinical effect of the supplementation was assessed by performing structured parental interviews. At baseline, patients were characterized by low or low–normal plasma vitamin E concentrations (7.19–15.68 μmol/L), while vitamin A concentrations were found to be normal or high (1.26–2.68 μmol/L). Vitamin E supplementation resulted in correction or significant elevation of plasma vitamin E concentration in all patients. We observed reduced aggression, self-injury, irritability, hyperactivity, attention deficit, repetitive behavior, sleep disturbance, skin photosensitivity and/or eczema in 3/6 patients, with notable individual variability. Clinical response to therapy was associated with a low baseline 7-DHC + 8-DHC/cholesterol ratio (0.2–0.4). We suggest that determination of vitamin E status is important in SLOS patients. Supplementation of vitamin E should be considered and might be beneficial.

Variant of bohring-opitz syndrome: A rare case report

Bohring–Opitz syndrome also known as Opitz C syndrome or Oberklaid–Danks syndrome is a rare syndrome. We are reporting a 2 months old male child with Bohring-Opitz like syndrome with all classical features and eventration of diaphragm (left side) which has not been reported yet with this syndrome. To our knowledge, a total of 23 cases with this syndrome have been reported in the medical literature to date and this is probably the first case report from India. Although there is overlap, a clinical distinction from the Bohring-Opitz syndrome and other syndromes seems possible, and thus a specific causal entity may be postulated.

Smith-Lemli-Opitz syndrome: Bosnian and Herzegovinian experience

The aim of this paper is to present a patient with the Smith-Lemli-Opitz syndrome (SLOS), with an overview of the modality of diagnosis, and the treatment of the patient. Exome analysis showed two variants in exon 6 of the 7-dehydrocholesterol reductase (DHCR7) gene have been determined: missense variant 1) NM_001360.2: c.470T>C (p.Leu157Pro) and 2) nonsense variant c.452G>A (W151*). Therefore the DHCR7 genotype of the patient is NM_001360.2: c.[470T>C; c.452G>A]. The proband, aged 6 years, has global developmental retardation with missing contact gaze and lacking motor development for her age and with peripheral spastic-enhanced muscle tone, and is under the supervision of children neurologists, gastroenterologists, nephrologists and cardiologists.