Achondrogenesis: A Lethal Chondrodystrophy.

Achondrogenesis is a type of skeletal dysplasia. Skeletal dysplasias are the heterogeneous class of bone growth disorders resulting in abnormal shape and size of the skeleton. Here, we present a rare case of achondrogenesis which was delivered by induced abortion at 6½ months of gestation. The physical, radiological, and ultrasonographic examinations done raised the possibility of this very rare anomaly. Achondrogensis is characterized by extreme micromelia and marked discrepancy between the relatively large head and the decreased trunk length. This rare condition has got genetic mutations associated with it. Achondrogenesis resembles other chondrodystrophies, therefore, its diagnosis needs to be made promptly and accurately.

Molecular analysis of a case of thanatophoric dysplasia reveals two de novo FGFR3 missense mutations located in cis

Thanatophoric dysplasia [TD] is the most common form of lethal skeletal dysplasia. It is primarily an autosomal dominant disorder and is characterised by macrocephaly, a narrow thorax, short ribs, brachydactyly, and hypotonia. In addition to these core phenotypic features, TD type I involves micromelia with bowed femurs, while TD type II is characterised by micromelia with straight femurs and a moderate to severe clover-leaf deformity of the skull. Mutations in the FGFR3 gene are responsible for all cases of TD reported to date. The objective of the study here was to delineate further the mutational spectrum responsible for TD. Conventional polymerase chain reaction [PCR], allele-specific PCR, and sequence analysis were used to identify FGFR3 gene mutations in a fetus with a lethal skeletal dysplasia consistent with TD, which was detected during a routine antenatal ultrasound examination. In this report we describe the identification of two de novo missense mutations in cis in the FGFR3 gene [p.Asn540Lys and p.Val555Met] in a fetus displaying phenotypic features consistent with TD. This is the second description of a case of TD occurring as a result of double missense FGFR3 gene mutations, suggesting that the spectrum of mutations involved in the pathogenesis of TD may be broader than previously recognised

Displasia tanatoforica: reporte de un caso / Thanatophoric dysplasia: a case report

Este caso concierne a paciente de 15 años quien fue referida del medio rural por presentar en su control pre-natal hallazgo ecográfico de malformación congénita: Polihidramnios severo, edema fetal generalizado (anasarca) hidrops no inmune con antecedente de hermano con malformación esuquelética congénita acondroplasia. Fue estudiada en el Servicio de ARO, observándose durante su hospitalización ausencia de frecuencia cardiaca fetal razón por la cual, se realiza inducción de trabajo de parto con obtención de producto con signos de maceración además de malformaciones esqueléticas en miembros superiores e inferiores, edema generalizado, desprendimiento de placenta 20 por ciento. Posteriormente se realiza curetaje uterino para verificar presencia o no de restos placentarios, después de 2 días de hospitalización la paciente se egresa debido a buena evolución clínica.

Thanatophoric dysplasia: roentgenographic findings and detection of a de novo mutation of FGFR3 gene in a Thai patient.

Thanatophoric dysplasia is the most common neonatal lethal skeletal dysplasia with an estimated incidence of 1 in 20,000 live births. This condition shares some similarity of radiological findings with other types of lethal skeletal dysplasias. Definite diagnosis is necessary for accurate medical and genetic counseling. The authors describe a male neonate who had characteristic features of thanatophoric dysplasia type I including severe shortening of limbs with redundant skin folds, large head, frontal bossing, depressed nasal bridge, and narrow thoracic cage with severe respiratory insufficiency. Postmortem radiographs revealed short ribs, flat vertebral bodies (platyspondyly), hypoplastic iliac bones, marked shortening of long bones including short and mild bowing of both femora, oval radiolucent area of proximal femur. Molecular analysis of Fibroblast Growth Factor Receptor 3 (FGFR3) gene identified a de novo mutation, p.R248C, in exon 7.

Displasia tantofórica / Thanatophoric dysplasia

Objetico: chamar atenção para a displasia tanatofórica, uma causa rara de insuficiência respiratória e a mais frequente condrodisplasia letal no recém-nascido. Descrição: o recém-nascido apresentava sinais de distúrbio respiratório. O fêmur em forma de telefone, um achado radiológico clássico, estava presente. /Objective: to focus attention on thanatophoric dwarfism, a rare cause of respiratory insufficiency and chondrodysplasia. The femur resembling a 'telephone receiver', a classical radiological finfing, was present...