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Nonimmune hydrops fetalis (NIHF) is a serious and complex fetal condition. Prenatal diagnosis of hydrops fetalis is not difficult by ultrasound. However, determining the underlying etiology of NIHF remains a challenge which is essential to address for prenatal counseling. We extracted DNA from a proband prenatally diagnosed unexplained NIHF. Trio-whole exome sequencing (WES) was performed to filter candidate causative variants. Two gene mutations were identified as a compound heterozygous state in the proband. Both variants located on the PIEZO1 gene: c.3895C > T, a missense mutation in exon 27 paternally inherited; c.4030_4032del, a maternally inherited in-frame deletion in exon 28. Both variants were first reported to be related to NIHF. PIEZO1 gene mutations, leading to an autosomal recessive congenital lymphatic dysplasia, which can present as NIHF and partial or complete resolution postnatally. In conclusion, WES can aid in the elucidation of the genetic cause of NIHF and has a positive effect on the assessment of prognosis. [ABSTRACT FROM AUTHOR]

Nonimmune hydrops fetalis (NIHF) is a serious and complex fetal condition. Prenatal diagnosis of hydrops fetalis is not difficult by ultrasound. However, determining the underlying etiology of NIHF remains a challenge which is essential to address for prenatal counseling. We extracted DNA from a proband prenatally diagnosed unexplained NIHF. Trio-whole exome sequencing (WES) was performed to filter candidate causative variants. Two gene mutations were identified as a compound heterozygous state in the proband. Both variants located on the PIEZO1 gene: c.3895C > T, a missense mutation in exon 27 paternally inherited; c.4030_4032del, a maternally inherited in-frame deletion in exon 28. Both variants were first reported to be related to NIHF. PIEZO1 gene mutations, leading to an autosomal recessive congenital lymphatic dysplasia, which can present as NIHF and partial or complete resolution postnatally. In conclusion, WES can aid in the elucidation of the genetic cause of NIHF and has a positive effect on the assessment of prognosis.

Background: Diabetes is a global disease with rapidly increasing prevalence in the world. Glycated hemoglobin (HbA1c) as an important indicator of diabetes could reflect the average serum glucose level over 120 days. However, when using HbA1c to diagnose diabetes, it is important to consider other factors that may impact HbA1c level including age, race/ethnicity, detection method, and co-morbidities. Here we report a case of diabetes with normal hemoglobin but reduced HbA1c.Case report: A 57-year-old female patient was diagnosed with diabetes by oral glucose tolerance test results. However, the HbA1c level was repeatedly decreased, glycated albumin level was high, with normal levels of hemoglobin and albumin, and a slightly elevated level of bilirubin. Moreover, life span of red blood cells was significantly shortened. Further examination of whole exome sequencing of the patient and her daughter showed heterozygous variant in PIEZO1 gene (c.6017T > A) in both, which is associated with dehydration hereditary stomatocytosis (DHS). After this diagnosis, we changed nateglinide to sitagliptin to reduce the burden of the pancreas islet function.Conclusion: In case of abnormally low HbA1c, we recommend that GA and reticulocyte should be measured simultaneously. Moreover, the methodology for hemoglobin measurement and the diseases that could cause abnormal quantity and quality of red blood cells and hemoglobin be considered.

Background: Diabetes is a global disease with rapidly increasing prevalence in the world. Glycated hemoglobin (HbA1c) as an important indicator of diabetes could reflect the average serum glucose level over 120 days. However, when using HbA1c to diagnose diabetes, it is important to consider other factors that may impact HbA1c level including age, race/ethnicity, detection method, and co-morbidities. Here we report a case of diabetes with normal hemoglobin but reduced HbA1c. Case report: A 57-year-old female patient was diagnosed with diabetes by oral glucose tolerance test results. However, the HbA1c level was repeatedly decreased, glycated albumin level was high, with normal levels of hemoglobin and albumin, and a slightly elevated level of bilirubin. Moreover, life span of red blood cells was significantly shortened. Further examination of whole exome sequencing of the patient and her daughter showed heterozygous variant in PIEZO1 gene (c.6017T > A) in both, which is associated with dehydration hereditary stomatocytosis (DHS). After this diagnosis, we changed nateglinide to sitagliptin to reduce the burden of the pancreas islet function. Conclusion: In case of abnormally low HbA1c, we recommend that GA and reticulocyte should be measured simultaneously. Moreover, the methodology for hemoglobin measurement and the diseases that could cause abnormal quantity and quality of red blood cells and hemoglobin be considered. [ABSTRACT FROM AUTHOR]

Hereditary xerocytosis (HX), also known as dehydrated stomatocytosis (DHSt) is a dominantly inherited genetic disorder exhibiting red cell membrane dehydration caused by the loss of the monovalent cation K+ and water. Variants in mechanosensitive Piezo ionic channels of the PIEZO1 gene are the primary cause of HX. We have utilized high throughput and highly precise next-generation sequencing (NGS) to make a diagnosis and examine the genotype-phenotype relationship in inflexible HX cases. Seven unrelated patients with unexplained hemolytic anemia were scrutinized with a panel probing 8000 genes related to congenital anemia. Targeted next-generation sequencing identified 8 missense variants in the PIEZO1 gene in 7 unrelated Indian patients. Three of the 8 variants are novel (c.1795G > C, c.2915G > A, c.7372 T > C) and the remaining five (c.4082A > G, c.6829C > A, c.7374C > G, c.7381G > A, c.7483_7488dup) are previously reported. The variants have been validated by Sanger sequencing. One patient with autosomal dominant mutation (c.7372 T > C) is associated with iron refractory iron deficiency anemia. Of the 7 patients, one has HX in combination with a novel homozygous variant (c.994G > A) in the PKLR gene causing PK deficiency resulting in severe clinical manifestations with phenotypic variability. In silico prediction using bioinformatics tools were used to study the possible damaging effects of the novel variants. Structural-functional analysis of the novel variants was investigated by molecular modeling software (PyMOL and Swiss PDB). These results encompass the heterogeneous behavior of mechano-sensitive Piezo1 protein observed in HX patients in India. Moreover, NGS imparted a subtle, economical, and quick tool for understanding the genetic cause of undiagnosed cases of congenital hemolytic anemia. NGS grants a potential technology integrating clinical history together with molecular report profiting in such patients and their families. [ABSTRACT FROM AUTHOR]

Hereditary xerocytosis (HX) is a rare, autosomal dominant congenital hemolytic anemia (CHA) characterized by erythrocyte dehydration with presentation of various degrees of hemolytic anemia. HX is often misdiagnosed as hereditary spherocytosis or other CHA. Here we report three cases of suspected HX and one case of HX associated with β-thalassemia. Sanger method was used for sequencing cDNA of the PIEZO1 gene. Variants were evaluated for potential pathogenicity by MutationTaster, PROVEAN, PolyPhen-2 and M-CAP software, and by molecular modeling. Four different variants in the PIEZO1 gene were found, including three substitutions (p.D669H, p.D1566G, p.T1732 M) and one deletion (p.745delQ). In addition, in the patient with the p.T1732 M variant we detected a 12-nucleotide deletion in the β-globin gene leading to a deletion of amino acids 62AHGK65. The joint presence of mutations in two different genes connected with erythrocytes markedly aggravated the presentation of the disease. Bioinformatic analysis and molecular modeling strongly indicated likely deleterious effects of all four PIEZO1 variants, but co-segregation analysis showed that the p.D1566G substitution is in fact non-pathogenic. Identification of causative mutations should improve the diagnosis and management of HX and provide a new insight into the molecular basis of this complex red blood cell abnormality. [ABSTRACT FROM AUTHOR]

Background: It is not easy to identify the cause of various iron overload diseases because the phenotypes overlap. Therefore, it is important to perform genetic testing to determine the genetic background of patients., Aim: To investigate the genetic background of a patient with hemochromatosis complicated by psoriasis on both lower extremities., Methods: Ten years ago, a 61-year-old male presented with iron overload, jaundice, hemolytic anemia and microcytic hypochromic anemia. Computed tomography of the left knee joint showed enlargement of the tibial medullary cavity and thinned bone cortices. Magnetic resonance imaging showed hepatic hemochromatosis, extensive abnormal signals from bone marrow cavities and nodular lesions in the lateral medullary cavity of the upper left lateral tibia. Single photon emission computed tomography showed radial dots of abnormal concentration in the upper end of the left tibia and radial symmetry of abnormal concentrations in joints of the extremities. The patient showed several hot spot mutations of the HFE and G6PD genes detected by next-generation sequencing, but no responsible gene mutation was found. The thalassemia gene was detected by gap-PCR., Results: The patient was found to carry the -α 4.2 and -- SEA deletion mutations of the globin gene. These two mutations are common causes of Southeast Asian α-thalassemia, but rarely cause severe widespread non-transfusion secondary hemochromatosis osteoarthropathy. The simultaneous presence of an auxiliary superposition effect of a rare missense mutation of the PIEZO1 gene (NM_001142864, c.C4748T, p.A1583V) was considered. Moreover, several rare mutations of the IFIH1, KRT8, POFUT1, FLG, KRT2, and TGM5 genes may be involved in the pathogenesis of psoriasis., Conclusion: The selection of genetic detection methods for hemochromatosis still needs to be based on an in-depth study of the clinical manifestations of the disease., Competing Interests: Conflict-of-interest statement: The authors do not have any conflict of interest to disclose., (©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.)