AUTHOR=Zhou Jianli , Zhao Yuzhen , Qian Xia , Cheng Yongwei , Cai Huabo , Chen Moxian , Zhou Shaoming 

TITLE=Two Novel Mutations in the SI Gene Associated With Congenital Sucrase-Isomaltase Deficiency: A Case Report in China

JOURNAL=Frontiers in Pediatrics

VOLUME=9

YEAR=2021

URL=https://www.frontiersin.org/journals/pediatrics/articles/10.3389/fped.2021.731716

DOI=10.3389/fped.2021.731716

ISSN=2296-2360

ABSTRACT=<p><bold>Background:</bold> Congenital sucrase-isomaltase deficiency (CSID) is an autosomal recessive inherited disease that leads to the maldigestion of disaccharides and is associated with mutation of the sucrase-isomaltase (<italic>SI</italic>) gene. Cases of CSID are not very prevalent in China or worldwide but are gradually being identified and reported.</p><p><bold>Case Presentation:</bold> We report a case involving a 14-month-old male who presented with failure to thrive that had begun after food diversification and was admitted for chronic diarrhea. We used a whole-exome sequencing (WES) approach to identify mutations in this patient's genome. WES revealed two novel heterozygous mutations in the <italic>SI</italic> gene, c.2626C &gt; T (p.Q876<sup>*</sup>) and c.2872C &gt; T (p.R958C), which were confirmed by Sanger DNA sequencing. With a strict sucrose- and starch-restricted diet, the patient's diarrhea was resolved, and he began to gain weight.</p><p><bold>Conclusions:</bold> We report a case of novel variants in the <italic>SI</italic> gene that caused CSID. This report provides valuable information for the clinical field, especially in China.</p>