[Dehydrated hereditary stomatocytosis in 23 cases: a single-center retrospective cohort study from Peking Union Medical College Hospital (2018-2024)].

Objective

Dehydrated hereditary stomatocytosis (DHS), a rare condition caused by pathogenic PIEZO1 or KCNN4 mutations, remains under-recognized. This study aimed to improve the diagnosis and management of DHS in China by retrospectively analyzing clinical and genetic characteristics.

Methods

Patients diagnosed with DHS at Peking Union Medical College Hospital between 2018 and 2024 were included. All had suspected congenital hemolytic anemia and were confirmed by next-generation sequencing to harbor pathogenic PIEZO1 or KCNN4 mutations. Clinical features, genotypes, iron overload, and treatment outcomes were collected and analyzed.

Results

Twenty-three DHS patients were identified, including 21 with PIEZO1 and 2 with KCNN4 mutations. Common manifestations were splenomegaly, jaundice, cholelithiasis, and secondary iron overload. Mild and moderate anemia occurred in 8.7% and 17.4% of patients, respectively, and stomatocytes were present in only 17.4%. The median time from symptom onset to diagnosis was 11 years. The predominant PIEZO1 variants were c.7367G > A and c.6328C > T, with nine novel mutations identified. Both KCNN4 mutations involved c.1055G > A. No clear genotype-phenotype correlation was observed. Secondary hepatic iron overload was found in 21.7% of patients.

Conclusion

DHS is often underdiagnosed or misdiagnosed. Genetic testing enables accurate identification, and regular monitoring for secondary hepatic iron overload is crucial for long-term management.