Introduction: Craniosynostosis is a craniofacial abnormality characterized by the premature ossification of one or more cranial sutures. In the literature, the cause of nonsyndromic craniosynostosis is attributed to a complex interaction between genetic and environmental factors. To our knowledge, there is no report in the literature of craniosynostosis occurring in each of three triplets.
Methods: We describe a case of spontaneous male triplets, each afflicted by craniosynostosis. The patients were the product of a non-consanguineous marriage and were delivered at 35 weeks’ gestation by a 38-year-old mother.
Results: The dichorionic triamniotic triplets consisted of a monochorionic-diamniotic pair (A and B) and a fraternal triplet (C). Examination of A and B revealed a palpable ridge along the sagittal suture. Examination of C revealed a palpable ridge along the metopic suture. Three-dimensional computed tomography scans confirmed sagittal synostosis in A and B and metopic synostosis in C. All patients underwent endoscopic strip craniectomy and were discharged by postoperative day two.
Conclusions: Current understanding of craniosynostosis involves an interaction between genetic and environmental factors. Increased concordance rates in monozygotic twins supports a genetic etiology while a concordance less than 100% suggests a multifactorial process which may also involve environmental and/or epigenetic influences. Involvement of the sagittal suture in the monozygotic twin pair and the metopic suture in the fraternal triplet substantiates the current understanding of craniosynostosis. Given the 100% concordance in this set of siblings, a genetic mechanism likely underlies the observed phenotype however environmental and/or epigenetic contributions cannot be excluded.
Patient Care: Although craniosynostosis is a commonly encountered condition, the pathogenesis remains poorly understood. This rare case serves to highlight how a combination of both genetic and environmental factors contribute to the development of this disease process. By recognizing these risk factors in our future patients, we can more easily identify which patients are at increased risk for craniosynostosis. Treatment can therefore be offered earlier and will ideally be performed in time to improve cosmesis and prevent possible neurological sequelae associated with craniosynostosis.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the pathoetiology of craniosynostosis, 2) Discuss the evidence for and against both genetic and environmental factors in the development of craniosynostosis