Diagnosis Of Skeletal Dysplasias Research Articles

A skeletal dysplasia leading to a perinatal death in 17th–19th century Lisbon, Portugal

AbstractCongenital skeletal disorders are a heterogeneous group of anomalies that become evident during gestation. They are expressed in the shape and growth of the bones during development because of a defective genetic background. With the follow‐up of pregnant women and the advances in prenatal ultrasonographic examination and molecular genetic tests, nowadays, congenital skeletal disorders are identified at an early gestational age. If they are considered lethal, the termination of pregnancy is advised. This work unveils an exceptional instance of a rare pathological condition identified in a perinate (birth ± 2 weeks) from the 17th to 19th centuries, recovered during an excavation at the cloister of the São Domingos Convent in Lisbon, Portugal. The skeleton presents with exuberant modifications that include, among others, severe shortening (micromelia) and bowing of the long bones of the upper and lower limbs. The main skeletal findings indicated a presumptive general diagnosis of skeletal dysplasia, while the differential diagnosis includes hypophosphatasia, campomelic dysplasia, achondrogenesis, thanatophoric dysplasia, and severe achondroplasia with developmental delay and acanthosis nigricans (SADDAN) as the most plausible causes for the observed skeletal changes. Even though an exact diagnosis is unattainable based only on the macroscopic analysis of the bones, the phenotypic features observed in this perinate are more consistent with thanatophoric dysplasia type 1.

Prenatal diagnosis of a skeletal disorder characterized by rhizomelic shortening of limbs caused by compound heterozygous variants in the PKDCC gene: Case report and literature review.

The protein kinase domain containing cytoplasmic (PKDCC) gene (OMIM#618821) is associated with bone development. Biallelic variants in the PKDCC gene can cause rhizomelic limb shortening with dysmorphic features. A fetus was found to be rhizomelic limb shortening at 16 weeks of gestation and amniocentesis was performed at 19 weeks of gestation. Genomic DNA extracted from the amniotic fluid was subjected to chromosomal microarray analysis (CMA), and Trio-total whole-exome sequencing (Trio-WES). Sanger sequencing was used to verify the candidate pathogenic variants. CMA was normal, while Trio-WES identified two compound heterozygous variants in the PKDCC gene, namely c.417_c.423delCGGCGCG insTCATGGGCTCAGTACAC(p.G140fs*35) and c.345G>A (p.W115*,379). Then the fetus was aborted and the development of its bone cells were compared with that of a normal fetus of similar gestational age by histopathological examination. Clinical findings of the fetus were shortening humerus and femur, synophrys, much hair on the side face, simian line on the right palm, etc. Histopathological examination showed that the affected fetus had increased proliferative chondrocytes, widened proliferative bands, and delayed bone mineralization. We reported a prenatal case of rhizomelic shortening of limbs caused by compound heterozygous variants in the PKDCC gene, which emphasized the important role of Trio-WES for diagnosis of skeletal dysplasia in fetuses.

Lung Hypoplasia in Fetuses with Skeletal Dysplasia Determined by Fetal Lung Weight: Which Ultrasound Measurement/Ratio Has the Highest Detection Rate

Introduction: To determine lung hypoplasia in cases with fetal skeletal dysplasia based on the total lung weight at autopsy as the most accountable surrogate marker for pulmonary hypoplasia. Methods: This retrospective cohort study included all pregnancies with antenatal diagnosis of skeletal dysplasia (2012–2018). We included only cases in which information on fetal biometry was available within 2 weeks before delivery and had autopsy and skeletal X-rays + molecular analysis using extracted fetal DNA. We compared the predictive accuracy of fetal sonographic body-proportional ratios (BPRs) including: (1) thoracic circumference-to-abdominal circumference ratio, (2) the femur length-to-abdominal circumference (FL/AC) ratio, (3) head circumference-to-abdominal circumference ratio, and (4) foot length-to-femur length ratio. Lung hypoplasia was defined as total lung weight below −2 SD from the expected mean for gestational age. Results: Fifty three pregnancies with antenatal diagnosis of skeletal dysplasia underwent autopsy included. Lung hypoplasia was determined in 34 (64.1%). Median of gestational age at last sonographic assessment was 21.3 (19.9–24.9) weeks. FL/AC ratio demonstrated the highest area under the curve of 0.817 (95% CI: 0.685–0.949; p < 0.0001). FL/AC ≤0.1550 demonstrated the highest detection rate of 88.2% along with the highest negative predictive value of 75%. Conclusion: Using a novel, more practical approach to predict lung hypoplasia in skeletal dysplasia, fetal sonographic BPRs and, specifically, FL/AC ratio demonstrate a high detection rate of lung hypoplasia.

Skeletal Dysplasia: A Case Report.

This paper presents a rare case of fetal hydrops detected at just 23 weeks of gestation in a 22-year-old woman's first pregnancy. The fetal ultrasound revealed severe skeletal anomalies, craniofacial deformities, and thoracic abnormalities, suggesting a complex and severe skeletal dysplasia, potentially type IA Achondrogenesis-a lethal autosomal recessive condition marked by ossification delay. This case highlights the significance of advanced genetic testing, such as next-generation sequencing (NGS) and whole-genome sequencing (WGS), in diagnosing and understanding skeletal dysplasias. Skeletal dysplasias represent a group of genetic disorders that affect osteogenesis. The prevalence of this condition is 1 in 4000 births. Sadly, 25% of affected infants are stillborn, and around 30% do not survive the neonatal period. There is a wide range of rare skeletal dysplasias, each with its own specific recurrence risk, dysmorphic expression, and implications for neonatal survival and quality of life. When skeletal dysplasia is incidentally discovered during routine ultrasound screening in a pregnancy not known to be at risk of a specific syndrome, a systematic examination of the limbs, head, thorax, and spine is necessary to reach the correct diagnosis. Prenatal diagnosis of skeletal dysplasia is crucial for providing accurate counselling to future parents and facilitating the proper management of affected pregnancies. An accurate diagnosis can be a real challenge due to the wide spectrum of clinical presentations of skeletal dysplasia but advances in imaging technologies and molecular genetics have improved accuracy. Additionally, some of these skeletal dysplasias may present clinical overlap, making it especially difficult to distinguish. After the 11th revision of genetic skeletal disorder nosology, there are 771 entities associated with 552 gene mutations. The most common types of skeletal dysplasia are thanatophoric dysplasia, osteogenesis imperfect, achondroplasia, achondrogenesis, and asphyxiating thoracic dystrophy.

Genetic diagnosis of skeletal dysplasias causing short stature in children

Short stature may often be due to skeletal dysplasias affecting the limbs, spine, or both. A careful clinical evaluation will help in identifying the rhizomelic and mesomelic shortening of the limbs and scoliosis. The mutations in different genes involved in various pathways in skeletal development lead to phenotypes that present from infancy to childhood or adulthood. A systematic clinical evaluation with identification of the limb bowing or deformity, dysmorphic features, radiological findings from skull to toes, and a single gene or multi-gene panel testing will help in making an appropriate diagnosis. The clinical clues to skeletal dysplasia include skeletal disproportion, unexplained limb bowing, recurrent fractures, facial dysmorphism including flat facies and blue sclera in severe cases, and sometimes typical digital or cardiac abnormalities. The following review focuses on the postnatal presentation of skeletal dysplasias mostly referred for evaluation of short stature.

Prenatal diagnosis to identify compound heterozygous variants in PKDCC that causes rhizomelic limb shortening with dysmorphic features in a fetus from China

BackgroundRhizomelic limb shortening with dysmorphic features (RLSDF) has already been a disorder of the rare autosomal recessive skeletal dysplasia, just having a few reported cases. RLSDF is caused by protein kinase domain containing, cytoplasmic(PKDCC)gene variants. In this study, we describe the clinical features and potential RLSDF molecular etiology in a fetus from China.MethodsGenomic DNA (gDNA) extracted from the fetal muscle tissue and parents’ peripheral blood was subjected to chromosomal microarray analysis (CMA) and trio-based whole exome sequencing (Trio-WES). The candidate pathogenic variants were verified by using Sanger sequencing.ResultsTrio-WES identified two compound heterozygous variants in PKDCC, c.346delC (p.Pro117Argfs*113) and c.994G > T (p.Glu332Ter), inherited from the father and mother, respectively. Both variants are classified as pathogenic according to American College of Medical Genetics and Genomics guidelines.ConclusionsWe reported the first prenatal case of RLSDF caused by PKDCC in the Chinese population. Our findings extended the variation spectrum of PKDCC and emphasized the necessity of WES for the early diagnosis of skeletal dysplasia and other ultrasound structural abnormalities in fetuses.

Skeletal Dysplasia Families: A Stepwise Approach to Diagnosis

Skeletal dysplasias are a heterogeneous collection of genetic disorders characterized by bone and cartilage abnormalities, and they encompass over 400 disorders. These disorders are rare individually, but collectively they are common (approximate incidence of one in 5000 births). Radiologists occasionally encounter skeletal dysplasias in daily practice. In the 1980s, Professor Juergen Spranger proposed a concept suitable for the diagnosis of skeletal dysplasias termed bone dysplasia families. He stated that (a) different bone dysplasias that share a similar skeletal pattern can be grouped into a "family," (b) the final diagnosis is feasible through the provisional recognition of a pattern followed by a more careful analysis, and (c) families of bone dysplasias may be the result of similar pathogenetic mechanisms. The prototypes of bone dysplasia families include dysostosis multiplex family, achondroplasia family, spondyloepiphyseal dysplasia congenita family, and Larsen syndrome-otopalatodigital syndrome family. Since Spranger's proposal, the concept of bone dysplasia families, along with advancing genetic techniques, has been validated and further expanded. Today, this molecularly proven concept enables a simple stepwise approach to be applied to the radiologic diagnosis of skeletal dysplasias. The first step is the categorization of a given case into a family based on pattern recognition, and the second step is more meticulous observation, such as identification of different severities of the same pattern or subtle but distinctive findings. Since major skeletal dysplasias are limited in number, radiologists can be familiar with the representative patterns of these disorders. The authors describe a stepwise radiologic approach to diagnosing major skeletal dysplasia families and review the clinical and genetic features of these disorders. Published under a CC BY 4.0 license. Quiz questions for this article are available through the Online Learning Center. Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article.

Genetic variations in the DYNC2H1 gene causing SRTD3 (short-rib thoracic dysplasia 3 with or without polydactyly).

Background and aims: Short-rib thoracic dysplasia 3 with or without polydactyly (SRTD3) represents a type of severe fetal skeletal dysplasia (SD) characterized by shortened limbs, narrow thorax with or without polydactyly, which is caused by the homozygous or compound heterozygous mutations in the DYNC2H1 gene. SRTD3 is a recessive disorder, identification of the responsible genetic variation would be beneficial to an accurate prenatal diagnosis and well-grounded counseling for the affected families. Material and methods: Two families having experienced recurrent fetal SDs were recruited and submitted to a multiplatform genetic investigation. Whole-exome sequencing (WES) was performed with samples collected from the probands. Sanger sequencing and fluorescent quantitative PCR (qPCR) were conducted as validation assays for suspected variations. Results: WES identified two compound heterozygous variations in the DYNC2H1(NM_001080463.2) gene, namely c.2386C>T (p.Arg796Trp) and c.7289T>C (p.Ile2430Thr) for one; and exon (64-83)del and c.8190G>T (p.Leu2730Phe) for the other, respectively. One variant in them, exon (64-83)del, was novelly identified. Conclusion: The study detected two compound heterozygous variation in DYNC2H1 including one novel deletion: exon (64-83) del. Our findings clarified the cause of fetal skeletal dysplasia in the subject families, provided guidance for their future pregnancies, and highlighted the value of WES in diagnosis of skeletal dysplasia with unclear prenatal indications.

Prenatal diagnosis of recurrent moderate skeletal dysplasias in lamin B receptors.

The lamin B receptor (LBR) gene is located in chromosome 1q42.12 and encodes the lamin B receptor, an intracellular protein that binds to lamin B. LBR mutations are associated with a broad phenotypic spectrum ranging from non-lethal to lethal skeletal dysplasias. The typical phenotypes include the Pelger-Huet anomaly (PHA) and embryonic lethal Greenberg dysplasia (GRBGD). With the further study of this gene, other phenotypes have been found in different individuals. This retrospective study analyzed recurrent prenatal moderate skeletal dysplasias in Chinese fetuses. Nothing malformed was detected in the fetal karyotype and microarray, while the whole-exome sequencing identified a homozygous variant (NM_002296.4:c.1757G>A, NP_002287.2:p.Arg586His) in exon 14 of the LBR gene in both fetuses. Mutation analysis in the parents confirmed that the c.1757G>A variation is heterozygous by Sanger sequencing. Intensive analysis on bioinformatics and familial co-segregation suggest that the homozygous variation in the LBR gene is responsible for this recurrent prenatal moderate skeletal dysplasia. Moreover, moderate skeletal dysplasias differ from typical GRBGD phenotypes. Our findings are based on the DNA base test and the prenatal diagnosis of skeletal dysplasia, which can be helpful in proper phenotyping and contribute to a better understanding of the correlation between the phenotype and genotype.

Radiological diagnosis of skeletal dysplasia

Radiological diagnosis of skeletal dysplasia

Elongation-Derotation-Flexion Casting Treatment of Early-Onset Progressive Scoliosis in Skeletal Dysplasia.

Early-onset scoliosis in children with skeletal dysplasia is progressive, contributing to cardiopulmonary restrictive disease. Serial elongation-derotation-flexion (EDF) casting, used in other etiologies of scoliosis to delay curve progression, may be beneficial in maximizing spine growth. Our hypothesis is serial EDF casting can be safely used as a temporary alternative to surgery, delaying progression and preserving growth, to treat scoliosis in skeletal dysplasia. All patients with skeletal dysplasia treated at a single institution with serial EDF casting for scoliosis were reviewed retrospectively. Radiographic parameters: Cobb angle of major and minor curves, curve location, thoracic height, thoracolumbar height, space available for lung, and rib vertebra angle difference were measured before casting (C1), in first casting (C2), in last casting (C3), and out of last casting (C4). Peak inspiratory pressure (PIP) values were monitored and recorded during the casting application. Eleven patients met the inclusion criteria (mean 9.7 castings). The mean duration of EDF serial casting was 35 months. The mean major Cobb angles were 54 degrees° (C1), 30 degrees (C2), 37 degrees (C3), and 49 degrees (C4) with no statistically significant differences. The mean minor Cobb angles were 35 degrees (C1), 25 degrees (C2), 33 degrees (C3), and 51 degrees (C4) with no statistically significant differences. The mean thoracic heights were 130 mm (C1), 155 mm (C2), 173 mm (C3), and 160 mm (C4). The 19-mm mean difference between C2 and C3 represents spinal growth. The PIP-1, PIP-2, and PIP-3 mean values were 15, 27, and 18 cmH2O, respectively. Changes in PIP-1 and PIP-2 and PIP-2 and PIP-3 were statistically significant. Serial EDF casting can delay surgical scoliosis correction in children younger than 7 years with a diagnosis of skeletal dysplasia. Our study showed that serial casting controls progression of the major curve and allows longitudinal growth of the spine with possible expansion of lung volume for nearly 3 years. During cast application, PIP increased with molding and traction, and improved until windowing and trimming of the cast. Level IV-retrospective study.

VP10.06: Approach to the diagnosis of skeletal dysplasia: further validation of an indigenous model

VP10.06: Approach to the diagnosis of skeletal dysplasia: further validation of an indigenous model

Prenatal diagnosis of a novel pathogenic variation in the ACAN gene presenting with isolated shortening of fetal long bones in the second trimester of gestation: a case report

BackgroundHeterozygous mutations of the ACAN gene are a major cause of different evolutive growth defects in the pediatric population, but were never described as a cause of fetal skeletal dysplasia.Case presentationA G1 at 21w + 3d came to our institution for the second-trimester ultrasound and a skeletal dysplasia with prevalent involvement of limb’s rhizomelic tracts was suspected. Amniocentesis followed by CGH-array was performed, with normal results. An examination by NGS of some genes associated with skeletal dysplasias showed a novel pathogenic variant of the ACAN gene: c.2677delG.ConclusionSequence variations of ACAN were never described as a possible cause of fetal skeletal anomalies to date. In this case report, we describe the first prenatal diagnosis of skeletal dysplasia associated with a pathogenic variant of ACAN.

EP346 - Diagnostic utility of next-generation sequencing panel tests in the diagnosis of skeletal dysplasias

eP346 - Diagnostic utility of next-generation sequencing panel tests in the diagnosis of skeletal dysplasias

Diagnosing Fetal Skeletal Dysplasia Using Three-Dimensional Computed Tomography: A Study Protocol for an Interventional Study

Background: Fetal skeletal dysplasias are a group of skeletal dysplasias occurring during the fetal stage. As the use of fetal ultrasonography has become widespread, the rate of prenatal diagnosis of skeletal dysplasias has increased. However, many fetal skeletal dysplasia phenotypes have indistinct definitions, making definitive prenatal diagnosis difficult. Fetal imaging methods that are the basis of diagnosing fetal skeletal dysplasias include ultrasonography and three-dimensional computed tomography. The use of three-dimensional computed tomography requires specific imaging techniques and cannot easily be performed at all facilities. In the present study, we propose to conduct a survey for the preparation of a protocol with a low risk, and a high diagnostic accuracy. Methods: In total, 50 pregnant women who undergo three-dimensional computed tomography for the diagnosis of fetal skeletal dysplasias will be included. The primary outcome is prenatal diagnostic accuracy for fetuses with skeletal dysplasias. The secondary outcome is the safety from radiation exposure. Results and conclusion: Three-dimensional computed tomography should be considered for the prenatal diagnosis of fetal skeletal dysplasias, as it is important to judge whether the prognosis is favorable or lethal. When considering the risk of radiation exposure, high quality images that are adequate for a diagnosis have been obtained using low-dose three-dimensional computed tomography scans. This approach reduces the level of radiation to which the pregnant woman and fetus are exposed. Trial registration: University hospital Medical Information Network (UMIN) Center: Trial registration number is UMIN000034744. Data of registration is October 01, 2018. (URL: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000039610)

Clinico – Radiological Study of Skeletal Dysplasias

Background: Skeletal dysplasia and osteochondrodysplasia refer to a genetically and clinically heterogeneous group of disorders of skeletal development and growth. Their prevalence is about 1 in 4000 births. Skeletal dysplasia is prevalent worldwide and its prevalence varies in different parts of the world and even in the same country varies from region to region. The objective is to study the prevalence of skeletal dysplasia based on clinico-radiological features. Subjects and Methods: A hospital retro prospective based study of skeletal dysplasia’s was conducted over a period of 2 years in which 100 cases of skeletal dysplasia’s were studied and were grouped according to international classification of osteochondrodysplasia’ s revised in 2006. Results: 100 cases of skeletal dysplasia’s were detected by various modes of examination like clinical, radiological (radiographs, USG, CT scan, MRI, echocardiography), genetic and biochemical tests. Among 100 cases 22 cases showed clinico-radiologically concordance, 45 cases showed clinico-radiological complement and 40 cases showed clinico-radiological discordance. Conclusion: Our study makes an important observation that only clinical evaluation detected only 20% of skeletal dysplasia’s; and hence the importance of clinic-radiological evaluation in the proper diagnosis of skeletal dysplasia’s.

Multiple occurrence of premature polyarticular osteoarthritis in an early medieval Bohemian cemetery (Prague, Czech Republic)

ObjectivesTo highlight conditions that may cause early-onset degenerative joint disease, and to assess the possible impact of such diseases upon everyday life. MaterialFour adults aged under 50 years from a medieval skeletal collection of Prague (Czechia). MethodsVisual, osteometric, X-ray, and histological examinations, stable isotope analysis of bone collagen. ResultsAll four individuals showed multiple symmetrical degenerative changes, affecting the majority of joints of the postcranial skeleton. Associated dysplastic deformities were observed in all individuals, including bilateral hip dysplasia (n = 1), flattening of the femoral condyles (n = 3), and substantial deformation of the elbows (n = 3). The diet of the affected individuals differed from the contemporary population sample. ConclusionsWe propose the diagnosis of a mild form of skeletal dysplasia in these four individuals, with multiple epiphyseal dysplasia or type-II collagenopathy linked to premature osteoarthritis as the most probable causes. SignificanceCombining the skeletal findings with information from the medical literature, this paper defines several characteristic traits which may assist with the diagnosis of skeletal dysplasia in the archaeological record. LimitationsAs no genetic analysis was performed to confirm the possible kinship of the individuals, it is not possible to definitively assess whether the individuals suffered from the same hereditary condition or from different forms of skeletal dysplasia. Suggestions for further researchFurther studies on premature osteoarthritis in archaeological skeletal series are needed to correct the underrepresentation of these mild forms of dysplasia in past populations.

Prenatal diagnosis of skeletal dysplasias using whole exome sequencing in China

BackgroundSkeletal dysplasias account for nearly 10% of fetal structural malformations detected by ultrasonography. This clinically heterogeneous group of genetic anomaly includes at least 461 genetic skeletal disorders with extreme clinical, phenotypic, and genetic heterogeneities, thus, significantly complicates accurate diagnosis. Researches have used whole exome sequencing (WES) for prenatal molecular diagnoses of skeletal dysplasias, however, data are still limited. MethodsDNA extracted from umbilical cord blood or amniocytes from fetuses suspected of skeletal dysplasias based on ultrasound evaluations were analyzed by WES. Blood samples were taken from the parents of the positive fetuses for co-segregation analysis using Sanger sequencing. ResultDefinitive molecular diagnosis was made in 6/8 (75%) cases, comprised of 5 de novo disease-causing changes in 3 genes (FGFR3, COL2A1, and COL1A2) and one proband with a biallelic deficiency for Lamin B Receptor(LBR),and including 3 novel variants. All fetuses had no detectable copy number variation (CNV) from sequencing results. ConclusionsOur study suggests that WES is an efficient approach for prenatal diagnosis of fetuses suspected of skeletal abnormalities and contributes to parental genetics counseling and pregnancy management.

Rapid prenatal diagnosis of skeletal dysplasia using medical trio exome sequencing: Benefit for prenatal counseling and pregnancy management.

The aim of this study is to explore the utility of rapid medical trio exome sequencing (ES) for prenatal diagnosis using the skeletal dysplasia as an exemplar. Pregnant women who were referred for genetic testing because of ultrasound detection of fetal abnormalities suggestive of a skeletal dysplasia were identified prospectively. Fetal samples (amniocytes or cord blood), along with parental blood, were send for rapid copy number variations testing and medical trio ES in parallel. Definitive molecular diagnosis was made in 24/27 (88.9%) cases. Chromosomal abnormality (partial trisomy 18) was detected in one case. Sequencing results had explained the prenatal phenotype enabling definitive diagnoses to be made in 23 cases. There were 16 de novo dominant pathogenic variants, four dominant pathogenic variants inherited maternally or paternally, two recessive conditions with pathogenic variants inherited from unaffected parents, and one X-linked condition. The turnaround time from receipt of samples in the laboratory to reporting sequencing results was within 2 weeks. Medical trio ES can yield very timely and high diagnostic rates in fetuses presenting with suspected skeletal dysplasia. These definite diagnoses aided parental counseling and decision making in most of cases.

Pseudodiastrophic dysplasia expands the known phenotypic spectrum of defects in proteoglycan biosynthesis

BackgroundPseudodiastrophic dysplasia (PDD) is a severe skeletal dysplasia associated with prenatal manifestation and early lethality. Clinically, PDD is classified as a ‘dysplasia with multiple joint dislocations’; however, the molecular aetiology...