Objective:To analyze the relationship between hematological and genotype characteristics of fetuses and patients with hemoglobin (Hb) H disease and their natural disease progression.Methods:From 2010 to 2022, a total of 1 252 blood samples from fetuses and patients with Hb H disease who visited the Guangxi Zhuang Autonomous Regional Maternal and Child Health Hospital were collected (including 174 umbilical cord blood samples, 1 062 peripheral blood samples from patients over 2 years old, and 16 peripheral blood samples from patients with rare cases of genotype Hb H). Additionally, 278 peripheral blood samples were collected from patients aged 0 - 2 years old with Hb H 3.7, Hb H 4.2, Hb H CS, and Hb H WS disease for the study of trends in red blood cell development. Multiple probe hybridization and microarray comparative genomic hybridization technology combined with first-generation Sanger sequencing were used for rare mutation detection.Results:Among the 1 062 Hb H disease patients over 2 years old, 62.34% (662/1 062) had gene deletion (--/-α), of which Hb H 3.7 (-- SEA/-α 3.7) and Hb H 4.2 (-- SEA/-α 4.2) were the most common, accounting for 42.28% (449/1 062) and 19.11% (203/1 062) of the total, respectively. Among the non-deletion genotypes (--/αα T or α Tα/αα T), Hb H CS (-- SEA/α CS), Hb H WS (-- SEA/α WS) and α CSα/α CSα accounted for 16.85% (179/1 062), 16.48% (175/1 062) and 1.98% (21/1 062), respectively. The 81.12% (537/662) of patients with deletional Hb H disease showed mild to moderate anemia, with Hb H detection rates ranging from 75% to 80%. Among non-deletional Hb H disease, Hb H WS disease showed the mild (blood Hb concentration > 95 g/L in 90% of patients) phenotype while Hb H CS and Hb H QS (-- SEA/αα QS) patients had moderate to severe anemia, with Hb H detected in peripheral blood at higher levels than in other types of Hb H disease patients. Except for Hb H CS and Hb H QS, which did not show a significant increase in Hb A2 levels when complicated with β-thalassemia, Hb A2 levels were increased (> 3.5%) in all other types of Hb H disease patients. When Hb H disease was complicated with β-thalassemia, Hb H peaks were not detected in either type of Hb H disease. The results of red blood cell development trend detection showed that erythrocyte counts were elevated in patients with Hb H disease compared to their normal counterparts; whereas, blood Hb, mean erythrocyte volume (MCV) and mean erythrocyte hemoglobin content (MCH) were lower than in their normal counterparts ( P < 0.05) and decreased to the minimum at 6 months to 1 year of age. Patients with Hb H CS disease, as the most severe form of anemia, had the highest MCV values ( P < 0.001). The results of fetal cord blood with Hb H disease showed that α CSα/α CSα caused severe intrauterine anemia, followed by Hb H QS and Hb H CS. The content of Hb Bart's in umbilical cord blood was negatively correlated with the severity of anemia ( rs = - 0.58, P < 0.001). When Hb H disease was complicated with β-thalassemia, there was no significant improvement in fetal anemia, and the Hb Bart's content did not change significantly ( P > 0.05). In addition, Hb H 21.9 (-α 21.9kb/-- SEA) and Hb H 2.4 (-α 2.4/-- SEA) were common in patients with deletion rare Hb H. In patients with non-deletion rare Hb H, αα Amsterdam-A1/-- SEA and αα Hb G-Georgia/-- SEA were both first reported. Conclusions:There is heterogeneity in clinical manifestations of patients with different types of Hb H disease or same type of Hb H disease at different developmental stages. When patients with Hb H are complicated with β-thalassemia, the phenotype of patients with the deletion type is improved, while that of patients with the non-deletion type is not. Compared to normal individuals, patients with Hb H disease have lower blood Hb concentration, MCV and MCH, and more rapid physiological changes in red blood cells.

Objective: Tracking the information on 1.69 million fetal cases across Guangxi Zhuang Autonomous Region (Guangxi) so as to study the occurrences of total and major birth defects in order to evaluate the ability on related prevention and control programs in Guangxi. Methods: Using the self-developed "Gui Women’s System" to establish a database of 1.69 million fetal cases in Guangxi and to analyze the distribution of time, space and population, as well as the outcomes of pregnancy, using the big data. Results: During the 29 months of observation, the overall live birth rate was 99.25%, with stillbirth rate during pregnancy as 0.44%, stillbirth rate during birth as 0.02%, and the 0-6 days mortality rate as 0.14%. The total detection rate on birth defects was 197.63/10 000; the incidence rate was 103.04/10 000, the birth rate was 102.55/10 000. The overall discovery rate of major birth defects was 48.33/10 000, with the incidence rate as 783 000, the birth rate as 0.58/10 000. The discovery rates of major birth defects in 14 cities were between 35 and 68/10 000, and the birth rate dropped significantly to less than 1.00 in 10 000. Nationalities showed that the number of pregnant women with birth defects more than 50 000 would include Hui (9.68/10 000), Yao (9.57/10 000), and Jing (9.37/10 000). With the increasing age of gestation, number of birth defects, incidence of major birth defects also increased. Ninety-five percent of the major birth defects were found within <28 weeks and with the top 5 kinds of major birth defects as complicated congenital heart disease (9.11/10 000), alpha thalassemia (8.36/10 000), and 21-trisomy syndrome (7.85/10 000), beta thalassemia (5.32/10 000) and fetal edema syndrome (4.92/10 000). The top 5 major birth defects appeared as complicated congenital heart disease (9.11/10 000), alpha thalassemia (8.36/10 000), and 21-trisomy syndrome (7.85/10 000), beta thalassemia (5.32/10 000) and fetal edema syndrome (4.92/10 000). Conclusion Programs leading to increase the rate on discovery of major birth defects were fundamental in effectively reducing the major birth defects.