Targeted screening for congenital cytomegalovirus: A micro-costing analysis.

AIM: We aimed to determine the cost and potential cost-savings of delivering a targeted congenital cytomegalovirus (cCMV) screening programme through a universal newborn hearing screening (UNHS) programme to detect cCMV-related hearing loss in infants from Victoria, Australia. METHODS: We completed a micro-costing analysis from a health-care perspective using data from a targeted cCMV screening programme piloted between June 2019 and March 2020. The programme involved collection of saliva samples to test for cCMV in infants who: received a 'refer' result on their second newborn hearing screen; were aged 21 days or less; and born at one of four maternity hospitals in Victoria, Australia. All costs to complete targeted cCMV screening were recorded in Australian 2020 dollars. Potential costs and benefits of adding targeted cCMV screening to the pre-existing UNHS programme were compared to when no screening was available up to 18 years to determine the likely cost or cost savings. RESULTS: The cost of adding targeted cCMV screening to Victoria's UNHS is $202 per infant screened. The total cost per positive case identified is $21 456. The overall cost of adding targeted salivary cCMV screening at the point of a second 'refer' result on the UNHS programme in Victoria's four largest hospitals is estimated to be $28 966 for the first year. CONCLUSION: Targeted screening for cCMV provides families the opportunity to detect and, if appropriate, treat cCMV in the first month of life in line with current recommendations. It falls within the range between cost neutral and cost saving.

Safe and effective use of a hybrid closed-loop system from diagnosis in children under 18 months with type 1 diabetes.

The management of type 1 diabetes in infancy presents significant challenges. Hybrid closed loop systems have been shown to be effective in a research setting and are now available for clinical use. There are relatively little reported data regarding their safety and efficacy in a real world clinical setting. We report two cases of very young children diagnosed with type 1 diabetes at ages 18 (Case 1) and 7 months (Case 2), who were commenced on hybrid closed-loop insulin delivery using the CamAPS FX™ system from diagnosis. At diagnosis, total daily dose (TDD) was 6 and 3.3 units for Case 1 and 2, respectively. Closed loop was started during the inpatient stay and weekly follow up was provided via video call on discharge. Seven months from diagnosis, Case 1 has an HbA1C of 49 mmol/mol, 61% time in range (TIR, 3.9-10 mmol/L) with 2% time in hypoglycemia (<3.9 mmol/L) with no incidents of very low blood glucose (BG; <3 mmol/L, 54 mg/dL) over 6 months. Given the extremely small TDD of insulin in Case 2, we elected to use diluted insulin (insulin aspart injection, NovoLog, Novo Nordisk Inc., Plainsboro, NJ, Diluting Medium for NovoLog®). Six months from diagnosis, the estimated HbA1c is 50 mmol/mol, TIR 76% with 1% hypoglycemia and no incidents of very low BG (<3 mmol/L, 54 mg/dL) over 6 months. We conclude that the use hybrid closed-loop can be safe and effective from diagnosis in children under 2 years of age with type 1 diabetes.

Feasibility and acceptability of targeted salivary cytomegalovirus screening through universal newborn hearing screening.

AIM: This study aimed to determine the feasibility and parental acceptability of screening for congenital cytomegalovirus (cCMV) through saliva polymerase chain reaction in infants who did not pass their newborn hearing screening. Additionally, the utility (i.e. time to diagnosis and treatment) of this enhanced clinical pathway was evaluated. METHODS: The study was conducted through the Victorian Infant Hearing Screening Programme (VIHSP) across four maternity hospitals in Melbourne, Australia, during June 2019-March 2020. Parents were approached by VIHSP staff about obtaining a test for cytomegalovirus (CMV) at the time of their baby's second positive ('refer') result on the VIHSP screen. Participating parents collected a saliva swab for CMV polymerase chain reaction from their infants. Feasibility was determined by the proportion of 'referred' infants whose parents completed the salivary CMV screening test ≤21 days of life. Acceptability was measured through parent survey. RESULTS: Of 126 eligible families, 96 (76.0%) had salivary screening swabs taken ≤21 days of life. Most families (>92.0%) indicated that screening was acceptable, straightforward and thought testing their baby for cCMV was a good idea. One infant screened positive on day 30, was diagnosed with cCMV via confirmatory testing by day 31 and commenced valganciclovir on day 32. CONCLUSIONS: Obtaining a saliva sample to screen for cCMV in infants who do not pass their newborn hearing screen is feasible and appears acceptable to parents. This targeted cCMV screening method could be an option where mothers are rapidly discharged from hospital, especially in the context of the COVID-19 pandemic.

Absence of the ER Cation Channel TMEM38B/TRIC-B Disrupts Intracellular Calcium Homeostasis and Dysregulates Collagen Synthesis in Recessive Osteogenesis Imperfecta.

Recessive osteogenesis imperfecta (OI) is caused by defects in proteins involved in post-translational interactions with type I collagen. Recently, a novel form of moderately severe OI caused by null mutations in TMEM38B was identified. TMEM38B encodes the ER membrane monovalent cation channel, TRIC-B, proposed to counterbalance IP3R-mediated Ca2+ release from intracellular stores. The molecular mechanisms by which TMEM38B mutations cause OI are unknown. We identified 3 probands with recessive defects in TMEM38B. TRIC-B protein is undetectable in proband fibroblasts and osteoblasts, although reduced TMEM38B transcripts are present. TRIC-B deficiency causes impaired release of ER luminal Ca2+, associated with deficient store-operated calcium entry, although SERCA and IP3R have normal stability. Notably, steady state ER Ca2+ is unchanged in TRIC-B deficiency, supporting a role for TRIC-B in the kinetics of ER calcium depletion and recovery. The disturbed Ca2+ flux causes ER stress and increased BiP, and dysregulates synthesis of proband type I collagen at multiple steps. Collagen helical lysine hydroxylation is reduced, while telopeptide hydroxylation is increased, despite increased LH1 and decreased Ca2+-dependent FKBP65, respectively. Although PDI levels are maintained, procollagen chain assembly is delayed in proband cells. The resulting misfolded collagen is substantially retained in TRIC-B null cells, consistent with a 50-70% reduction in secreted collagen. Lower-stability forms of collagen that elude proteasomal degradation are not incorporated into extracellular matrix, which contains only normal stability collagen, resulting in matrix insufficiency. These data support a role for TRIC-B in intracellular Ca2+ homeostasis, and demonstrate that absence of TMEM38B causes OI by dysregulation of calcium flux kinetics in the ER, impacting multiple collagen-specific chaperones and modifying enzymes.

Karyotype - Phenotype Associations in Patients with Turner Syndrome.

Variation in karyotype may be associated with the phenotype of patients with Turner syndrome (TS). Our objective was to identify these associations between karyotype and phenotype in TS patients. This study was part of the European multicentre dsd-LIFE study. We evaluated the associations between different karyotypes of TS patients and age at diagnosis, Turner stigmata, cardiac/renal involvement and gonadal function. Information was available for 328 TS patients. Participants had a monosomy 45,X (46%), mosaicism 45,X/46,XX (10%), karyotype with isochromosome (18%), or other karyotype (26%). The clinical signs of TS were the most severe in patients with monosomy 45,X and the least severe in patients with mosaicism 45,X/46,XX. Patients with isochromosome and y-material showed an intermediate phenotype. Despite the more severe features in patients with monosomy 45,X, the median age at diagnosis was only slightly lower compared to patients with other karyotypes, which suggests opportunities for improvement of knowledge and diagnostics.

Phenotypic variability in patients with osteogenesis imperfecta caused by BMP1 mutations.

Osteogenesis Imperfecta (OI) is an inherited bone fragility disorder most commonly associated with autosomal dominant mutations in the type I collagen genes. Autosomal recessive mutations in a number of genes have also been described, including the BMP1 gene that encodes the mammalian Tolloid (mTLD) and its shorter isoform bone morphogenic protein-1 (BMP1). To date, less than 20 individuals with OI have been identified with BMP1 mutations, with skeletal phenotypes ranging from mild to severe and progressively deforming. In the majority of patients, bone fragility was associated with increased bone mineral density (BMD); however, the full range of phenotypes associated with BMP1 remains unclear. Here, we describe three children with mutations in BMP1 associated with a highly variable phenotype: a sibship homozygous for the c.2188delC mutation that affects only the shorter BMP1 isoform and a further patient who is compound heterozygous for a c.1293C>G nonsense mutation and a c.1148G>A missense mutation in the CUB1 domain. These individuals had recurrent fractures from early childhood, are hypermobile and have no evidence of dentinogenesis imperfecta. The homozygous siblings with OI had normal areal BMD by dual energy X-ray absorptiometry whereas the third patient presented with a high bone mass phenotype. Intravenous bisphosphonate therapy was started in all patients, but discontinued in two patients and reduced in another due to concerns about increasing bone stiffness leading to chalk-stick fractures. Given the association of BMP1-related OI with very high bone material density, concerns remain whether anti-resorptive therapy is indicated in this ultra-rare form of OI.© 2016 Wiley Periodicals, Inc.

ARNT2 mutation causes hypopituitarism, post-natal microcephaly, visual and renal anomalies.

We describe a previously unreported syndrome characterized by secondary (post-natal) microcephaly with fronto-temporal lobe hypoplasia, multiple pituitary hormone deficiency, seizures, severe visual impairment and abnormalities of the kidneys and urinary tract in a highly consanguineous family with six affected children. Homozygosity mapping and exome sequencing revealed a novel homozygous frameshift mutation in the basic helix-loop-helix transcription factor gene ARNT2 (c.1373_1374dupTC) in affected individuals. This mutation results in absence of detectable levels of ARNT2 transcript and protein from patient fibroblasts compared with controls, consistent with nonsense-mediated decay of the mutant transcript and loss of ARNT2 function. We also show expression of ARNT2 within the central nervous system, including the hypothalamus, as well as the renal tract during human embryonic development. The progressive neurological abnormalities, congenital hypopituitarism and post-retinal visual pathway dysfunction in affected individuals demonstrates for the first time the essential role of ARNT2 in the development of the hypothalamo-pituitary axis, post-natal brain growth, and visual and renal function in humans.

Hearing Screening for Congenital CytoMegaloVirus-Exploring Parents' Experiences of Completing Targeted Congenital Cytomegalovirus Screening at the Time of Their Infants' Newborn Hearing Screening.

Background/Objectives: Congenital cytomegalovirus (cCMV) is the leading infectious cause of sensorineural hearing loss and neurodevelopmental disabilities, with prompt detection (<21 days of life) required to enable accurate diagnosis and anti-viral treatment where clinically appropriate. International guidelines recommend cCMV screening for infants who do not pass their Universal Newborn Hearing Screening (UNHS). This study aimed to explore parental experiences of targeted cCMV screening through the UNHS in Victoria, Australia between 2019 and 2020 (HearS-cCMV study). Methods: A qualitative study comprising 18 semi-structured interviews with parents who took saliva swabs from their infants who did not pass their UNHS. A maximum variation sampling strategy was used with data analysed using thematic analysis. Results: Four themes described 18 parents' experiences of cCMV screening: (1) parents' lack of CMV awareness prior to cCMV screening; (2) overall positive experience; (3) varied understanding of CMV post screening; and (4) parents were glad to screen their infant for cCMV. Enablers of targeted cCMV screening included the swab being simple and non-invasive, being easier to complete in the hospital than at home, and the screening being well delivered by the staff. Barriers included a potential increase in anxiety, especially with false positives, and the timing of cCMV screening coinciding with their infant not passing UNHS being difficult for some parents. Conclusions: Parent experiences of targeted cCMV screening were positive. Increasing public knowledge of cCMV and training staff members to complete the CMV swab would reduce the risk of false positives and associated parental anxiety. This would facilitate successful routine targeted cCMV screening.

Discovery of Protease-Activated Receptor 4 (PAR4)-Tethered Ligand Antagonists Using Ultralarge Virtual Screening.

Here, we demonstrate a structure-based small molecule virtual screening and lead optimization pipeline using a homology model of a difficult-to-drug G-protein-coupled receptor (GPCR) target. Protease-activated receptor 4 (PAR4) is activated by thrombin cleavage, revealing a tethered ligand that activates the receptor, making PAR4 a challenging target. A virtual screen of a make-on-demand chemical library yielded a one-hit compound. From the single-hit compound, we developed a novel series of PAR4 antagonists. Subsequent lead optimization via simultaneous virtual library searches and structure-based rational design efforts led to potent antagonists of thrombin-induced activation. Interestingly, this series of antagonists was active against PAR4 activation by the native protease thrombin cleavage but not the synthetic PAR4 agonist peptide AYPGKF.