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Background: TRNT1 (CCA-adding transfer RNA nucleotidyl transferase) enzyme deficiency is a new metabolic disease caused by defective post-transcriptional modification of mitochondrial and cytosolic transfer RNAs (tRNAs).Results: We investigated four patients from two families with infantile-onset cyclical, aseptic febrile episodes with vomiting and diarrhoea, global electrolyte imbalance during these episodes, sideroblastic anaemia, B lymphocyte immunodeficiency, retinitis pigmentosa, hepatosplenomegaly, exocrine pancreatic insufficiency and renal tubulopathy. Other clinical features found in children include sensorineural deafness, cerebellar atrophy, brittle hair, partial villous atrophy and nephrocalcinosis. Whole exome sequencing and bioinformatic filtering were utilised to identify recessive compound heterozygous TRNT1 mutations (missense mutation c.668T>C, p.Ile223Thr and a novel splice mutation c.342+5G>T) segregating with disease in the first family. The second family was found to have a homozygous TRNT1 mutation (c.569G>T), p.Arg190Ile, (previously published). We found normal mitochondrial translation products using passage matched controls and functional perturbation of 3' CCA addition to mitochondrial tRNAs (tRNA(Cys), tRNA(LeuUUR) and tRNA(His)) in fibroblasts from two patients, demonstrating a pathomechanism affecting the CCA addition to mt-tRNAs. Acute management of these patients included transfusion for anaemia, fluid and electrolyte replacement and immunoglobulin therapy. We also describe three-year follow-up findings after treatment by bone marrow transplantation in one patient, with resolution of fever and reversal of the abnormal metabolic profile.Conclusions: Our report highlights that TRNT1 mutations cause a spectrum of disease ranging from a childhood-onset complex disease with manifestations in most organs to an adult-onset isolated retinitis pigmentosa presentation. Systematic review of all TRNT1 cases and mutations reported to date revealed a distinctive phenotypic spectrum and metabolic and other investigative findings, which will facilitate rapid clinical recognition of future cases. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate cerebral magnetic resonance imaging (MRI) scans of children with prenatal drug exposure in a clinical context. A hospital-based cohort of 10- to 14-year-old children, prenatally exposed to alcohol, opioids, and polysubstances, and a group of sex- and age-matched controls were examined with cerebral MRI. Scans obtained from 34 exposed children and 40 controls were scored based on the presence and degree of pathology by an experienced pediatric neuroradiologist blinded to the participants’ background. Overall visual detectable MRI pathology was found in 35% of the exposed children and 33% of the controls (odds ratio = 1.08; 95% confidence interval = 0.36-3.25). No specific imaging pattern following prenatal drug exposure was seen by the means of simple visual analysis of cerebral MRI scans. Although cerebral MRI is feasible, it is probably of limited value in the clinical assessment of children with prenatal drug exposure. [ABSTRACT FROM AUTHOR]

Objectives: To compare the diagnostic yield of whole-body post-mortem computed tomography (PMCT) imaging to post-mortem magnetic resonance (PMMR) imaging in a prospective study of fetuses and children.Methods: We compared PMCT and PMMR to conventional autopsy as the gold standard for the detection of (a) major pathological abnormalities related to the cause of death and (b) all diagnostic findings in five different body organ systems.Results: Eighty two cases (53 fetuses and 29 children) underwent PMCT and PMMR prior to autopsy, at which 55 major abnormalities were identified. Significantly more PMCT than PMMR examinations were non-diagnostic (18/82 vs. 4/82; 21.9 % vs. 4.9 %, diff 17.1 % (95 % CI 6.7, 27.6; p < 0.05)). PMMR gave an accurate diagnosis in 24/55 (43.64 %; 95 % CI 31.37, 56.73 %) compared to 18/55 PMCT (32.73 %; 95 % CI 21.81, 45.90). PMCT was particularly poor in fetuses <24 weeks, with 28.6 % (8.1, 46.4 %) more non-diagnostic scans. Where both PMCT and PMMR were diagnostic, PMMR gave slightly higher diagnostic accuracy than PMCT (62.8 % vs. 59.4 %).Conclusion: Unenhanced PMCT has limited value in detection of major pathology primarily because of poor-quality, non-diagnostic fetal images. On this basis, PMMR should be the modality of choice for non-invasive PM imaging in fetuses and children.Key Points: • Overall 17.1 % more PMCT examinations than PMMR were non-diagnostic • 28.6 % more PMCT were non-diagnostic than PMMR in fetuses <24 weeks • PMMR detected almost a third more pathological abnormalities than PMCT • PMMR gave slightly higher diagnostic accuracy when both were diagnostic. [ABSTRACT FROM AUTHOR]

Background Adrenal vein sampling ( AVS) is useful for distinguishing unilateral versus bilateral hypersecretion in primary aldosteronism ( PA), but is technically challenging. Furthermore, the use of adrenocorticotropic hormone ( ACTH)-stimulation in AVS is controversial. We implemented a Monash Health-specific AVS protocol in 2010. Aim The audit aimed to: (i) examine the impact of a dedicated protocol on success rates of AVS at a tertiary referral centre; (ii) evaluate the impact of AVS on sub-typing of PA; and (iii) assess the utility of ACTH stimulation in AVS. Methods AVS was performed on patients with PA confirmed by positive saline suppression testing (aldosterone level >140 pmol/L post-saline infusion), with sequential sampling of adrenal and peripheral veins, pre- and post- ACTH infusion. Patients with unilateral aldosterone-producing adenoma diagnosed on successful AVS were referred for adrenalectomy. Results Between 2010 and 2014 inclusive, a total of 28 AVS procedures was performed, with complete pre- and post- ACTH data for 19 procedures. Bilateral successful cannulation rates improved post-implementation of our protocol (61% vs 41%). Of the patients, 32% had discordant imaging and AVS results: four patients with unilateral adenomas did not lateralise on AVS and were managed medically; four patients with bilateral or no adenomas on imaging, lateralised on AVS and had surgery. Overall, use of ACTH did not increase successful cannulation and tended to mask lateralisation. Conclusion AVS is crucial in subtype classification of PA and should be performed by a dedicated radiologist with a standardised protocol. AVS outcomes were not improved with the use of ACTH stimulation. [ABSTRACT FROM AUTHOR]

Background The primary purpose of this study was to report on an evaluation of the perceptions and beliefs of service providers towards family-centred practices in 11 early intervention programmes for infants and young children in Singapore. Methods The Measure of Processes of Care for Service Providers (MPOC-SP) and Measure of Beliefs about Participation in Family-Centred Service (MBP-FCS) were administered to 213 service providers made up of teachers, therapists, psychologists and social workers providing centre-based therapy to children with special needs who were below the age of 6 years. Results Exploratory factor analyses were performed with both scales. Nineteen of the 27 MPOC-SP items were retained and supported the original four-factor structure model. The exploratory factor analyses on MBP-FCS provided a less satisfactory outcome. Fourteen of the 28 items were retained and these loaded onto four factors. The two factors relating to Beliefs about benefits of FCS and Beliefs about the absence of negative outcomes from FCS failed to emerge as separate factors. Further multiple regressions indicated that more direct work with families and positive self-efficacy in implementing FCS contributed significantly to explaining service providers' positive perception towards family-centred practice in service delivery. Conclusions This is the first time MPOC-SP and MBP-FCS were administered to a population in an Asian context. While MBP-FCS would benefit from further development work on its construct, MPOC-SP offered important insights into service providers' perspectives about family-centred practices that would have useful implications for professional and service development. [ABSTRACT FROM AUTHOR]

The transcription factor SOX2 is expressed most notably in the developing CNS and placodes, where it plays critical roles in embryogenesis. Heterozygous de novo mutations in SOX2 have previously been associated with bilateral anophthalmia/microphthalmia, developmental delay, short stature, and male genital tract abnormalities. Here we investigated the role of Sox2 in murine pituitary development. Mice heterozygous for a targeted disruption of Sox2 did not manifest eye defects, but showed abnormal anterior pituitary development with reduced levels of growth hormone, luteinizing hormone, and thyroid-stimulating hormone. Consequently, we identified 8 individuals (from a cohort of 235 patients) with heterozygous sequence variations in SOX2. Six of these were de novo mutations, predicted to result in truncated protein products, that exhibited partial or complete loss of function (DNA binding, nuclear translocation, or transactivation). Clinical evaluation revealed that, in addition to bilateral eye defects, SOX2 mutations were associated with anterior pituitary hypoplasia and hypogonadotropic hypogonadism, variable defects affecting the corpus callosum and mesial temporal structures, hypothalamic hamartoma, sensorineural hearing loss, and esophageal atresia. Our data show that SOX2 is necessary for the normal development and function of the hypothalamo-pituitary and reproductive axes in both humans and mice. [ABSTRACT FROM AUTHOR]