[Genetic and clinical analysis of a child with Shwachman-Diamond syndrome due to compound heterozygous variants of SBDS gene].

OBJECTIVE: To analyze the clinical features and genetic characteristics of a patient with Shwachman-Diamond syndrome (SDS) due to compound heterozygous variants of SBDS gene.

METHODS: A female child with SDS who was admitted to the Children's Hospital Affiliated to Zhengzhou University in February 2022 was selected as the study subject. Clinical data of the child was collected. Peripheral blood samples of the child and her elder sister and parents were collected and subjected to whole exome sequencing (WES). Candidate variant was verified by Sanger sequencing.

RESULTS: The child, a 1-year-and-1-month-old girl, had mainly manifested with diarrhea, hematochezia, growth retardation and malnutrition, along with increased transaminases and decreased neutrophils and hemoglobin. Anteroposterior X-ray of her left wrist indicated significantly delayed bone age. Colonoscopy revealed that her colorectal mucosa was erosive with oily food residues attached to the intestinal lumen. Genetic testing revealed that she has harbored c.258+2T>C and c.100A>G compound heterozygous variants of the SBDS gene. The c.258+2T>C variant has derived from her father and known to be pathogenic, whilst the other has derived from her mother. Based on the guidelines from the American College of Medical Genetics and Genomics, the c.100A>G variant was classified as likely pathogenic (PM1+PM2_Supporting+PM3+PM5+PP3).

CONCLUSION: The compound heterozygous variants of c.258+2T>C and c.100A>G probably underlay the SDS in this child. For children with refractory diarrhea, liver damage and growth retardation, SDS should be suspected, and genetic testing can facilitate the diagnosis and treatment.