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      <JournalTitle>Frontiers in Medical Case Reports</JournalTitle>
      <Volume-Issue>Volume 1; Issue 5</Volume-Issue>
      <Season>(Sep-Oct, 2020)</Season>
      <ArticleType>Medical Case Reports</ArticleType>
      <ArticleTitle>Connective Tissue Disorders: One of The Main Differential Diagnosis of Congenital Hypotonia</ArticleTitle>
      <Abstract>Loeys-Dietz syndrome (LDS) is an autosomal dominant connective tissue disorder that has been associated with mutations involving the TGFBR1/2, SMAD2/3, and TGFB2/3 genes. It is characterized by aneurysms, arterial tortuosity, hypertelorism and bifid uvula. We present the case of a full-term infant born with significant hypotonia and congenital anomalies who was eventually diagnosed with LDS. Physical findings were significant for decreased muscle tone, redundant skin on nape of the neck, small chin, widely spaced nipples, and bilateral club feet. Due to the multiple anomalies noted above, genetics consultation was obtained. A chromosomal analysis with reflex to SNP microarray analysis was performed, showing a normal female 46,XX. Given the complex nature of the patient’s presentation and normal initial genetics studies, Whole Exome Sequencing (WES) was ordered, revealing a heterozygous –likely De Novo, pathogenic variant in the TGFBFR1 gene (p.Glu239del), consistent with autosomal dominant LDS. Upon literature review, different cases of LDS associated with congenital hypotonia have been described. Nevertheless, medical attention was often sought for other clinical indications such as musculoskeletal and cardiac abnormalities, with some cases mislabeled as Larsen or Beals syndrome. We propose that connective tissue disorders should be included in the main differential diagnosis of congenital hypotonia.</Abstract>
      <Keywords>Loeys-Dietz syndrome (LDS),Congenital hypotonia,Connective tissue disorders</Keywords>
        <Abstract>https://www.jmedicalcasereports.org/ubijournal-v1copy/journals/abstract.php?article_id=8153&amp;title=Connective Tissue Disorders: One of The Main Differential Diagnosis of Congenital Hypotonia</Abstract>
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