Severe spinal deformity (Cobb angle > 90°) often leads to cardiopulmonary dysfunction, posing significant surgical risks. We report a rare case of severe kyphoscoliosis with cardiopulmonary failure treated with non-invasive ventilation, anti-shock treatment, Halo-pelvic traction (HPT), and orthopedic surgery, emphasizing the importance of multidisciplinary cooperation. A 13-year-old Boy with genetic suspicion of distal arthrogryposis (Type 5D) presented with Cobb angles of 94° (scoliosis) and 69° (kyphosis), respiratory failure (PO2 36.3 mmHg), and pre-shock status. A multidisciplinary team stabilized the patient using non-invasive ventilation, nutritional optimization and HPT. Post-traction correction rates reached 46.8% (coronal) and 53.6% (sagittal). Subsequent posterior spinal fusion (T1-L5) achieved 69% correction, resolving cardiopulmonary dysfunction and resulting in a highly satisfactory therapeutic outcome. This case illustrates a case with severe spinal deformity combined with extremely severe cardiopulmonary dysfunction and highlights the importance of multidisciplinary cooperation in high-risk pediatric patients.

To explore the clinical phenotypes and genetic characteristics of a pedigree with Distal arthrogryposis type 5D (DA5D) caused by compound heterozygous variants in the ECEL1 gene. A child (proband) diagnosed with DA5D and his family members (proband's parents and sister) who was admitted to the Department of Rehabilitation Medicine of Henan Children's Hospital in July 2022 due to "multiplex distal arthrogryposis" were enrolled into this study. Clinical data of the proband were collected and peripheral blood samples were obtained from the proband and members of his family about 3 mL. Trio-whole genome sequencing (trio-WGS) was carried out to detected the genetic variations of the proband and his family members. The candidate's pathogenic gene variants were screened and analyzed by Genome Aggregation Database (gnomAD) and other databases. The screened variants were annotated for clinical phenotypes using databases like the Online Mendelian Inheritance in Man (OMIM). The pathogenicity of the candidate variants was predicted by bioinformatics tools such as Provean. Based on the guidelines of the American College of Medical Genetics and Genomics (ACMG), pathogenicity ratings were conducted for variant sites. The protein conservation and mutation structure prediction of ECEL1 protein among species were carried out though MEGA-X and PyMOL. The research protocol of this study was reviewed by the Ethics Committee of Henan Provincial Children's Hospital (Approval No. 2023-H-H01), and informed consent for clinical research was obtained from the guardians of the probands. The proband had multiplex distal arthrogryposis involving hands, feet, knees, and ankles, and had right ptosis, micrognathia, low auricular position, and upturned nose. The parents and sister both had normal phenotypes. Trio-WGS and Sanger sequencing revealed that the child had compound heterozygous variants of paternal c.1742_c.1743insT and maternal c.2314T>G, for which the father and sister were carriers of the c.1742_c.1743insT heterozygous variant and the mother was carrier of c.2314T>A. Neither mutation site has been reported. According to guidelines of ACMG, the c.1742_c.1743insT variant was classified as likely pathogenic (PSV1+PM2_Supporting), and c.2314T>G was classified as uncertain (PM2_Supporting+PM3+PP3). The results of conserved analysis of amino acid residue sequences of ECEL1 protein showed that the missense mutation of the maternal c.2314T>G (p.Cys772Gly) was highly conserved among humans and other seven species. The protein structure prediction revealed that the c.1742_c.1743insT frameshift mutation led to the protein truncation, and the c.2314T>G missense mutation resulted in the failure of forming 1 disulfide bond. The compound heterozygous variants of ECEL1 gene were considered to be pathogenic for this DA5D patient, which have expanded the mutational spectrum of the ECEL1 gene and provided a reference for clinical diagnosis as well as genetic counseling for this family.

Arthrogryposis multiplex congenita involves joint contractures across various body parts. Distal arthrogryposis type 5D (DA5D) is a rare, autosomal recessive subtype affecting distal extremities, with symptoms like knee extension contractures, camptodactyly, overriding fingers, ulnar wrist deviation, and scoliosis. A 24-year-old pregnant woman with a second-degree relative partner had a fetus showing increased nuchal translucency (3.4 mm) and high Down syndrome risk in the first-trimester screen. Both parents were healthy and had no known family history of hereditary diseases. Genetic counselling and amniocentesis at 16 weeks revealed a segmental gain on chromosome 1p31.1 of uncertain significance, ruling out aneuploidies of chromosomes 21, 18, and 13. Later scans suggested fetal akinesia deformation sequence (FADS) with limited limb movement. Whole exome sequencing confirmed DA5D due to a novel ECEL1 5' splice site variant (c.2151 + 2T > A) inherited autosomally recessive. The couple chose pregnancy termination, with an autopsy confirming DA5D. This case expands the mutational spectrum of prenatal ECEL1 gene using whole exome sequencing (WES) for fetal joint disorders, potentially helping in parental counselling and clinical decision-making.

Distal arthrogryposis type 5D (DA5D) represents a subtype of distal arthrogryposis (DA) characterized by congenital joint contractures in the distal extremities. DA5D is inherited in a rare autosomal recessive manner and is associated with the ECEL1 gene. In this report, we describe a case of an infant with bilateral knee contractures and ptosis, caused by a novel compound heterozygous mutation of ECEL1. We conducted DNA extraction, whole-exome sequencing analysis, and mutation analysis of ECEL1 to obtain genetic data on the patient. We subsequently analyzed the patient's clinical and genetic data. The proband was a 6 months-old male infant who presented with significant bilateral knee contracture disorders and bilateral ptosis. MRI demonstrated cartilage degradation in knee joint. Whole-exome sequencing of the patient's DNA revealed a compound heterozygous mutation of c.2152-15C>A and c.110_155del in ECEL1. Analysis with the MutationTaster application indicated that c.110_155del was pathogenic (probability = 1), causing frameshift mutations affecting 151 amino acids (p.F37Cfs*151). The truncated protein lost the substructure of a transmembranous site based on the predicted protein crystal structure AF-O95672-F1. The variant of c.2152-15C>A of ECEL1 was also predicted to be disease-causing (probability = 0.98) as it impaired the methylation of ECEL1 serving as an H3K27me3 modification site, which led to the dysfunction of the second topological domain. Therefore, we concluded that the compound heterozygous mutation caused the pathogenic phenotype of this proband. The present case highlights the usefulness of molecular genetic screening in diagnosing unexpected joint disorder. Identification of novel mutations in the ECEL1 gene broadens the mutation spectrum of this gene and adds to the genotype-phenotype map of DA5D. Furthermore, rapid whole-exome sequencing analysis enabled timely diagnosis of this rare disease, facilitating appropriate treatment and scheduled follow-up to improve clinical outcomes.

Distal arthrogryposis type 5D (DA5D) is clinically characterized by knee extension contractures, distal joint contractures, clubfoot, micrognathia, ptosis, and scoliosis. We report nine affected individuals from eight unrelated Indian families with DA5D. Although the overall musculoskeletal phenotype is not very distinct from other distal arthrogryposis, the presence of fixed knee extension contractures with or without scoliosis could be an important early pointer to DA5D. We also report a possible founder variant in ECEL1 along with four novel variants and further expand the genotypic spectrum of DA5D.