Germline ERG haploinsufficiency defines a new syndrome with cytopenia and hematological malignancy predisposition.

The genomics era has facilitated discovery of new genes predisposing to bone marrow failure (BMF) and hematological malignancy (HM). We report the discovery of ERG as a novel autosomal dominant BMF/HM predisposition gene. ERG is a highly constrained transcription factor critical for definitive hematopoiesis, stem cell function and platelet maintenance. ERG colocalizes with other transcription factors including RUNX1 and GATA2 on promoters/enhancers of genes orchestrating hematopoiesis. We identified a rare heterozygous ERG missense variant in 3 thrombocytopenic individuals from one family and 14 additional ERG variants in unrelated individuals with BMF/HM including 2 de novo cases and 3 truncating variants. Phenotypes associated with pathogenic germline ERG variants included cytopenias (thrombocytopenia, neutropenia, pancytopenia) and HMs (acute myeloid leukemia, myelodysplastic syndrome, acute lymphoblastic leukemia) with onset before 40 years. Twenty ERG variants (19 missense, 1 truncating) including 3 missense population variants were functionally characterized. Thirteen potentially pathogenic ETS domain missense variants displayed loss-of-function characteristics disrupting transcriptional transactivation, DNA-binding and/or nuclear localization. Selected variants overexpressed in mouse fetal liver cells failed to drive myeloid differentiation and cytokine-independent growth in culture, and to promote acute erythroleukemia when transplanted into mice, concordant with these variants being loss-of-function. Four individuals displayed somatic genetic rescue by copy neutral loss of heterozygosity. Identification of predisposing germline ERG variants has clinical implications for patient/family diagnosis, counselling, surveillance, and treatment strategies including selection of bone marrow donors or cell/gene therapy.

Management of childbearing with hypermobile Ehlers-Danlos syndrome and hypermobility spectrum disorders: A scoping review and expert co-creation of evidence-based clinical guidelines.

OBJECTIVE: To co-create expert guidelines for the management of pregnancy, birth, and postpartum recovery in the context of hypermobile Ehlers-Danlos syndrome (hEDS) and hypermobility spectrum disorders (HSD). DESIGN: Scoping Review and Expert Co-creation. SETTING: United Kingdom, United States of America, Canada, France, Sweden, Luxembourg, Germany, Italy, and the Netherlands. SAMPLE: Co-creators (n = 15) included expertise from patients and clinicians from the International Consortium on the Ehlers-Danlos syndromes and Hypermobility Spectrum Disorders, facilitated by the Ehlers-Danlos Society. METHODS: A scoping review using Embase, Medline, the Cochrane Central Register of Controlled Trials and CINHAL was conducted from May 2022 to September 2023. Articles were included if they reported primary research findings in relation to childbearing with hEDS/HSD, including case reports. No language limitations were placed on our search, and our team had the ability to translate and screen articles retrieved in English, French, Spanish, Italian, Russian, Swedish, Norwegian, Dutch, Danish, German, and Portuguese. The Mixed Methods Appraisal Tool was used to assess bias and quality appraise articles selected. The co-creation of guidelines was based on descriptive evidence synthesis along with practical and clinical experience supported by patient and public involvement activities. RESULTS: Primary research studies (n = 14) and case studies (n = 21) including a total of 1,260,317 participants informed the co-creation of guidelines in four overarching categories: 1) Preconceptual: conception and screening, 2) Antenatal: risk assessment, management of miscarriage and termination of pregnancy, gastrointestinal issues and mobility, 3) Intrapartum: risk assessment, birth choices (mode of birth and intended place of birth), mobility in labor and anesthesia, and 4) Postpartum: wound healing, pelvic health, care of the newborn and infant feeding. Guidelines were also included in relation to pain management, mental health, nutrition and the common co-morbidities of postural orthostatic tachycardia syndrome, other forms of dysautonomia, and mast cell diseases. CONCLUSIONS: There is limited high quality evidence available. Individualized strategies are proposed for the management of childbearing people with hEDS/HSD throughout pregnancy, birth, and the postpartum period. A multidisciplinary approach is advised to address frequently seen issues in this population such as tissue fragility, joint hypermobility, and pain, as well as common comorbidities, including dysautonomia and mast cell diseases.

Vascular Ehlers-Danlos Syndrome: A Comprehensive Natural History Study in a Dutch National Cohort of 142 Patients.

BACKGROUND: Vascular Ehlers-Danlos syndrome (vEDS) is a rare connective tissue disorder with a high risk for arterial, bowel, and uterine rupture, caused by heterozygous pathogenic variants in COL3A1. The aim of this cohort study is to provide further insights into the natural history of vEDS and describe genotype-phenotype correlations in a Dutch multicenter cohort to optimize patient care and increase awareness of the disease. METHODS: Individuals with vEDS throughout the Netherlands were included. The phenotype was charted by retrospective analysis of molecular and clinical data, combined with a one-time physical examination. RESULTS: A total of 142 individuals (50% female) participated the study, including 46 index patients (32%). The overall median age at genetic diagnosis was 41.0 years. More than half of the index patients (54.3%) and relatives (53.1%) had a physical appearance highly suggestive of vEDS. In these individuals, major events were not more frequent (P=0.90), but occurred at a younger age (P=0.01). A major event occurred more often and at a younger age in men compared with women (P<0.001 and P=0.004, respectively). Aortic aneurysms (P=0.003) and pneumothoraces (P=0.029) were more frequent in men. Aortic dissection was more frequent in individuals with a COL3A1 variant in the first quarter of the collagen helical domain (P=0.03). CONCLUSIONS: Male sex, type and location of the COL3A1 variant, and physical appearance highly suggestive of vEDS are risk factors for the occurrence and early age of onset of major events. This national multicenter cohort study of Dutch individuals with vEDS provides a valuable basis for improving guidelines for the diagnosing, follow-up, and treatment of individuals with vEDS.

Impressive clinical improvement and disappearance of neuropathic pain in an adult patient with hypophosphatasia treated with asfotase alfa.

Hypophosphatasia (HPP) is a rare disorder, resulting from loss-of-function variants of the ALPL gene encoding non-tissue specific alkaline phosphatase (TNSALP). Presentation varies largely, with increased severity usually occurring with earlier disease onset. Here we describe the clinical improvement of a 57-year-old woman with childhood onset HPP, after initiating treatment with asfotase alfa (Strensiq®). This was started because of the rapid and progressive radiological deterioration of bone structure after placement of nails in both upper legs for spontaneous atypical femur fracture (AFF) - like fractures. Initiation of treatment, not only resulted in stabilization of bone structure on X-rays, but within a few weeks there was a dramatic reduction of burning pain sensations in the lower legs, attributed in retrospect to neuropathic pain, and also almost complete disappearance of headaches. Additionally, unhealed metatarsal fractures finally healed after almost 10 years. Drug efficacy was further evaluated through -quality of life questionnaires and multiple tests conducted by the physiotherapist, and showed clear improvements. Within 3 months after starting asfotase alfa, the patient was able to carry out her daily tasks indoors without relying on a walker and even started electric bike rides for 20 km/day. In conclusion, treatment with asfotase alfa, halted rapid radiological bone deterioration after bilateral intramedullary femoral pen placement and strongly increased quality of life, marked by rapid disappearance of neuropathic pain, reduction in headaches and musculoskeletal pains, and enhanced muscle strength and mobility. The quick and almost complete disappearance of neuropathic pain and headache suggests a relation with disturbed levels of metabolites in HPP.