RESUMEN
INTRODUCTION: Counseling osteogenesis imperfecta (OI) pregnancies is challenging due to the wide range of onsets and clinical severities, from perinatal lethality to milder forms detected later in life. METHODS: Thirty-eight individuals from 36 families were diagnosed with OI through prenatal ultrasonography and/or postmortem clinical and radiographic findings. Genetic analysis was conducted on 26 genes associated with OI in these subjects that emerged over the past 20 years; while some genes were examined progressively, all 26 genes were examined in the group where no pathogenic variations were detected. RESULTS: Prenatal and postnatal observations both consistently showed short limbs in 97%, followed by bowing of the long bones in 89%. Among 32 evaluated cases, all exhibited cranial hypomineralization. Fractures were found in 29 (76%) cases, with multiple bones involved in 18 of them. Genetic associations were disclosed in 27 families with 22 (81%) autosomal dominant and five (19%) autosomal recessive forms, revealing 25 variants in six genes (COL1A1, COL1A2, CREB3L1, P3H1, FKBP10, and IFITM5), including nine novels. Postmortem radiological examination showed variability in intrafamily expression of CREBL3- and P3H1-related OI. CONCLUSION: Prenatal diagnosis for distinguishing OI and its subtypes relies on factors such as family history, timing, ultrasound, genetics, and postmortem evaluation.
Asunto(s)
Osteogénesis Imperfecta , Humanos , Osteogénesis Imperfecta/genética , Osteogénesis Imperfecta/diagnóstico por imagen , Femenino , Embarazo , Ultrasonografía Prenatal , Cadena alfa 1 del Colágeno Tipo I , Proteínas de Unión a Tacrolimus/genética , Masculino , Colágeno Tipo I/genética , Autopsia , Prolil Hidroxilasas/genética , Adulto , Glicoproteínas de Membrana , Proteínas de la Membrana , ProteoglicanosRESUMEN
Osteogenesis imperfecta (OI) is a heterogeneous group of diseases affecting type I collagen and characterized by bone fragility. Lethal forms are rare and are characterized by micromelia associated with limb deformities. We report two cases of prenatally diagnosed lethal OI. Patients underwent ultrasound examination at 17 and 25 weeks of amenorrhoea, supplemented with fetal skeletal CT scanning in one case. Therapeutic abortion was recommended in both cases.