A Chinese pediatric patient with thalassemia traits and compound heterozygous mutations in the PIEZO1 gene suspected of having dehydrated hereditary stomatocytosis.

BACKGROUND

Dehydrated Hereditary Stomatocytosis (DHS), also known as Hereditary Xerocytosis (HX), is a rare genetic disorder primarily arising from gain-of-function mutations in PIEZO1, which disrupt mechanosensitive ion channels on red blood cell membranes. This dysfunction leads to cellular dehydration and chronic anemia, while DHS/HX cells exhibit increased hypotonic resistance. Interpreting PIEZO1 variants requires integrating clinical findings with specialized knowledge.

METHODS

Laboratory tests, whole-genome sequencing, and Sanger sequencing were conducted for clinical phenotyping and identification of disease-causing mutations within the proband and his parents.

RESULTS

The proband was found to have both β-thalassemia trait and Dehydrated Hereditary Stomatocytosis. The proband inherited compound heterozygous mutations in the PIEZO1 gene (c.136G > A and c.6307C > G) from his mother and father, respectively. Additionally, the proband had a heterozygous β-globin gene mutation (c.315 + 2delT) inherited from his father.

CONCLUSION

Compared to patients with either DHS/HX or β-thalassemia alone, this patient, as a β-thalassemia carrier with suspected Dehydrated Hereditary Stomatocytosis, exhibited highly complex laboratory findings. Genetic testing played a crucial role in diagnosing conditions with overlapping clinical features. Given the increased risk of thromboembolic complications, splenectomy is contraindicated in DHS/HX patients, highlighting the necessity for precise diagnosis of DHS/HX and molecular confirmation of suspected hereditary red blood cell disorders.