Clinical manifestations and gene analysis of 18 cases of hereditary protein S deficiency / 中华血液学杂志

Objective: To analyze the clinical manifestations and molecular pathogenesis of 18 patients with inherited protein S (PS) deficiency. Methods: Eighteen patients with inherited PS deficiency who were admitted to the Institute of Hematology & Blood Diseases Hospital from June 2016 to February 2019 were analyzed: activity of protein C (PC) and antithrombin (AT) , PS activity were measured for phenotype diagnosis; high throughput sequencing (HTS) was used for screening of coagulation disease-related genes; Sanger sequencing was used to confirm candidate variants; Swiss-model was used for three-dimensional structure analysis. Results: The PS:C of 18 patients ranged from 12.5 to 48.2 U/dL. Among them, 16 cases developed deep vein thrombosis, including 2 cases each with mesenteric vein thrombosis and cerebral infarction, and 1 case each with pulmonary embolism and deep vein thrombosis during pregnancy. A total of 16 PROS1 gene mutations were detected, and 5 nonsense mutations (c.134_162del/p.Leu45*, c.847G>T/p.Glu283*, c.995_996delAT/p.Tyr332*, c.1359G> A/p.Trp453*, c.1474C>T/p.Gln492*) , 2 frameshift mutations (c.1460delG/p.Gla487Valfs*9 and c.1747_1750delAATC/p.Asn583Wfs*9) and 1 large fragment deletion (exon9 deletion) were reported for the first time. In addition, the PS:C of the deep vein thrombosis during pregnancy case was 55.2 U/dL carrying PROC gene c.565C>T/p.Arg189Trp mutation. Conclusion: The newly discovered gene mutations enriched the PROS1 gene mutation spectrum which associated with inherited PS deficiency.

A family of hereditary protein S deficiency with the onset of pulmonary embolism and literature review / 中华儿科杂志

Objective: To explore the clinical characteristics and genotype of PROS1 gene related hereditary protein S deficiency (PSD) with the onset of pulmonary embolism in children. Methods: A family with pulmonary embolism was diagnosed as hereditary PSD in the Department of Pediatrics of Peking University First Hospital in November 2020, and the clinical data, including clinical manifestations, laboratory tests, imaging and genetic results, were collected for a retrospective research. The family members were also screened for protein S activity and PROS1 gene mutations. A literature search with "PROS1" "protein S deficiency" "homozygous" and "complex heterozygous" as key words was conducted at PubMed, China National Knowledge Infrastructure, and Wanfang Data Knowledge Service Platform (up to October 2021). Case reports of patients with PROS1 gene homozygous or complex heterozygous variants and related clinical features, protein S activity, and genotype were reviewed and analyzed. Results: The proband, a 14-year-old girl, was admitted to the hospital for a 9-day history of coughing and a 4-day history of chest pain in November 2020. After admission, laboratory tests showed that D-dimer was 8.38 mg/L (reference:<0.24 mg/L). An urgent CT pulmonary angiography confirmed bilateral pulmonary embolism and right lower pulmonary infarction, while an ultrasonography showed deep vein thrombosis in her left leg. Further examination revealed that protein S activity was less than 10%. The proband's second sister, a 12-year-old girl, was admitted to the hospital in December 2020. Her protein S activity was 8% and an ultrasonography showed deep vein thrombosis in her right leg. The protein S activity of the proband's father and mother were 36% and 26%, respectively. Trio-whole-exome sequencing detected compound heterozygous PROS1 gene variants (c.-168C>T and c.200A>C (p.E67A)) for the proband and her second sister, that were inherited from her father and mother, respectively. The proband's third sister's protein S activity was 28%; she and the proband's grandfather both carried c.200A>C (p.E67A) variants. The proband and her younger sister were treated with rivaroxaban and responded well during the 3-month follow-up. A total of 1 Chinese report in literature and 18 English literature were retrieved and 14 patients with protein S deficiency caused by homozygous or complex heterozygous variants of PROS1 gene were enrolled, including 8 male and 6 female patients. The ages ranged from 4 days to 35 years. Three patients experienced fulminant purpura or severe intracranial hemorrhage in early neonatal-period, while the remaining 11 patients developed venous thromboembolism in adolescence. Protein S activity was examined in 11 patients, and all showed less than 10% of activity. Missense variants was the most common type of gene variants. Conclusions: For children with pulmonary embolism, if there are no clear risk factors for thrombosis, hereditary protein S deficiency should be considered, and protein S activity should be examined before oral anticoagulant drugs. If protein S activity is less than 10%, protein S deficiency caused by homozygous or complex heterozygous variants should be considered.

Trombofilia primaria: detección y manifestación clínica en 105 casos / Primary thombophilia: Report of 93 cases and 12 asymptomatic relatives

Background: Thrombophilia is defined as an altered hemostasis that predisposes to thrombosis. It can be primary when there is a family clustering of the disease or secondary, when it is associated to an acquired risk factor. Aim: To report clinical features in a series of patients with primary thrombophilia. Material and methods: Review of clinical records of patients with thrombotic episodes that lead to the suspicios of primary thrombophilia. Analysis of asymptomatic adult close relatives of these patients. Results: We report 93 subjects (56 females, age range 14-77 years) with repeated episodes of thrombosis and a family history of thrombosis and 12 asymptomatic close relatives. Seventy one percent had the first thrombotic episode before the age of 40 years, 62% had more than one thrombotic episode and 37% had a family history of thrombosis. Twenty four percent had protein C deficiency, 24% had antithrombin III deficiency, 18% had resistance to activated C protein by factor V Leiden, 10% had protein S deficiency, and 10% had the G20210 mutation of prothrombin gene. Among acquired defects studied simultaneously, 30% had lupus anticoagulant and 11% had hyperhomocysteinemia. Twenty four percent of cases had more than one thrombophilic risk factor. Among asymptomatic relatives, five had factor V Leiden, four had protein C deficiency and three had the G20210 mutation of prothrombin gene. Conclusions: Thrombophilia must be suspected in young subjects with thrombotic episodes and a family history. The type of coagulation defect will determine prognosis, and the type of treatment.

Trombose de veia cava em adolescente com deficiência de proteínas "C" e "S" / Vena cava thrombosis in a teenager with protein

Relata-se o caso de um adolescente com 14 anos de idade, do sexo masculino, que apresentava diagnóstico de deficiência de proteína C e S e desnvolveu trombose de veia cava após treino de capoeira. Enfatiza-se os achados clínicos e dados relevantes de literatura e alerta-se para os cuidados preventivos