A Novel Homozygous Missense Variant in the LRRC32 Gene Is Associated With a New Syndrome of Cleft Palate, Progressive Vitreoretinopathy, Growth Retardation, and Developmental Delay.

Cleft lip and/or cleft palate are a common group of birth defects that further classify into syndromic and non-syndromic forms. The syndromic forms are usually accompanied by additional physical or cognitive abnormalities. Isolated cleft palate syndromes are less common; however, they are associated with a variety of congenital malformations and generally have an underlying genetic etiology. A single report in 2019 described a novel syndrome in three individuals, characterized by cleft palate, developmental delay and proliferative retinopathy due to a homozygous non-sense mutation in the LRRC32 gene encoding glycoprotein A repetitions predominant (GARP), a cell surface polypeptide crucial for the processing and maturation of transforming growth factor ß (TGF-ß). We describe a patient who presented with cleft palate, prenatal and postnatal severe growth retardation, global developmental delay, dysmorphic facial features and progressive vitreoretinopathy. Whole exome sequencing (WES) revealed a very rare homozygous missense variant in the LRRC32 gene, which resulted in substitution of a highly conserved isoleucine to threonine. Protein modeling suggested this variant may negatively affect GARP function on latent TGF-ß activation. In summary, our report further expands the clinical features of cleft palate, proliferative retinopathy and developmental delay syndrome and emphasizes the association of LRRC32 pathogenic variants with this new syndrome.

Plasma metabolomics reveals a diagnostic metabolic fingerprint for mitochondrial aconitase (ACO2) deficiency.

Mitochondrial respiratory chain dysfunction has been identified in a number of neurodegenerative disorders. Infantile cerebellar-retinal degeneration associated with mutations in the mitochondrial aconitase 2 gene (ACO2) has been recently described as a neurodegenerative disease of autosomal recessive inheritance. To date there is no biomarker for ACO2 deficiency and diagnosis relies on genetic analysis. Here we report global metabolic profiling in eight patients with ACO2 deficiency. Using an LC-MS-based metabolomics platform we have identified several metabolites with affected plasma concentrations including the tricarboxylic acid cycle metabolites cis-aconitate, isocitrate and alpha-ketoglutarate, as well as phosphoenolpyruvate and hydroxybutyrate. Taken together we report a diagnostic metabolic fingerprint for mitochondrial aconitase 2 deficiency.

Severe Acute Mastoiditis Admission is Not Related to Delayed Antibiotic Treatment for Antecedent Acute Otitis Media.

BACKGROUND: Delayed antibiotic treatment for acute otitis media (AOM) is recommended for children >6 months with nonsevere illness, no risk factors for complications or history of recurrent AOM. This study evaluates relationship between delayed antibiotic treatment for antecedent AOM and severity of subsequent acute mastoiditis admission. METHODS: A prospective observational study of children aged 0-14 years admitted with acute mastoiditis to 8 hospitals between 2007 and 2012 calculates rates of severe acute mastoiditis admission [defined by ≥1 of the following: complication (mastoid subperiosteal abscess, brain abscess and sagittal vein thrombosis), need for surgical procedure and duration of admission >6 days].Severe acute mastoiditis admissions in children with antecedent AOM treated with immediate antibiotics were compared with those with delayed antibiotic treatment. RESULTS: Antecedent AOM was diagnosed in 216 of 512 acute mastoiditis admissions (42.1%), of whom 159 (73%) immediately received antibiotics, and 57 (27%) had delayed antibiotic treatment. Higher rate of recurrent AOM was noted in the immediate compared with delayed antibiotic treatment group (29% vs. 8.7%, P = 0.0021). Complication rates were 19.5% versus 10.5% (P = 0.12), rates of surgical procedures required, 30% versus 10% (P = 0.0033); admission rates >6 days, 37% versus 29% (P = 0.28) for immediate antibiotic therapy and delayed antibiotic treatment. On logistic regression analysis, immediately treated AOM patients had increased need for surgery for acute mastoiditis with adjustment for history of recurrent AOM (relative risk: 3.2, 95% confidence interval: 1.4-7.0). CONCLUSIONS: Delayed antibiotic treatment for antecedent AOM is not associated with an increase in severity parameters in subsequent acute mastoiditis admission.