Response to Kosaki et al. “Molecular pathology of Shprintzen-Goldberg syndrome”

Craniosynostosis, Scheuermann's disease, and intellectual disability resembling Shprintzen-Goldberg syndrome: a report on a family over 4 generations: Case report

RATIONALE

Craniosynostosis is a disorder characterized by premature fusion of cranial sutures with subsequent development of abnormal craniofacial contour associated with variable skeletal and extra-skeletal abnormalities. In this family syndromic type of craniosynostosis was recognized and the etiology behind diverse forms of deformities have been diagnosed.

PATIENT CONCERNS

The negative impact of the disorder on the child and his family is enormous. Particularly when the diagnosis is late and little can be done. Though counselling the family through discussing the whole picture of the disorder might lessens their concern.

DIAGNOSES

Diagnosis is the corner stone of management. In this paper we aimed to sensitize pediatricians, physicians, and orthopedic surgeons concerning the necessity to recognize syndromic associations early on.

INTERVENTIONS

Patients with syndromic craniosynostosis are usually associated with a complexity of malformation complex. Craniofacial surgery can be of remarkable help if the diagnosis is made early. It requires a series of corrections to avoid intellectual disability and other neurological deficits.The timing of interventions is strongly correlated on the timing of diagnosis.

OUTCOMES

The earliest the diagnoses, the much better the outcomes are. And consequently avert the psychological and the financial cost on the patient and his family.

LESSONS

The golden principle of medicine should prevail in all medical disciplines, which states: The more you see, the more you know and conversely the more you know is the more you see.

Loeys-Dietz syndrome: cardiovascular, neuroradiological and musculoskeletal imaging findings

Loeys-Dietz syndrome (LDS) is an increasingly recognized autosomal-dominant connective tissue disorder with distinctive radiological manifestations, including arterial tortuosity/aneurysms, craniofacial malformations and skeletal abnormalities. LDS exhibits a more aggressive course than similar disorders, such as Marfan or the vascular subtype of Ehlers-Danlos syndrome, with morbidity and mortality typically resulting from complications of aortic/arterial dissections. Early diagnosis, short-interval follow-up imaging and prophylactic surgical intervention are essential in preventing catastrophic cardiovascular complications. This review focuses on the cardiovascular, neuroradiological and musculoskeletal imaging findings in this disorder and recommendations for follow-up imaging.

Recent progress in genetics of Marfan syndrome and Marfan-associated disorders

Marfan syndrome (MFS, OMIM #154700) is a hereditary connective tissue disorder, clinically presenting with cardinal features of skeletal, ocular, and cardiovascular systems. In classical MFS, changes in connective tissue integrity can be explained by defects in fibrillin-1, a major component of extracellular microfibrils. However, some of the clinical manifestations of MFS cannot be explained by mechanical properties alone. Recent studies manipulating mouse Fbn1 have provided new insights into the molecular pathogenesis of MFS. Dysregulation of transforming growth factor beta (TGFbeta) signaling in lung, mitral valve and aortic tissues has been implicated in mouse models of MFS. TGFBR2 and TGFBR1 mutations were identified in a subset of patients with MFS (MFS2, OMIM #154705) and other MFS-related disorders, including Loeys-Dietz syndrome (LDS, #OMIM 609192) and familial thoracic aortic aneurysms and dissections (TAAD2, #OMIM 608987). These data indicate that genetic heterogeneity exists in MFS and its related conditions and that regulation of TGFbeta signaling plays a significant role in these disorders.

FBN1, TGFBR1, and the Marfan-craniosynostosis/mental retardation disorders revisited

The recent identification of TGFBR2 mutations in Marfan syndrome II (MFSII) [Mizuguchi et al. (2004); Nat Genet 36:855-860] and of TGFBR1 and TGFBR2 mutations in Loeys-Dietz aortic aneurysm syndrome (LDS) [Loeys et al. (2005); Nat Genet 37:275-281] [OMIM 609192] has provided direct evidence of abnormal signaling in transforming growth factors beta (TGF-beta) in the pathogenesis of Marfan syndrome (MFS). In light of this, we describe the phenotypes and genotypes of five individuals. Patient 1 had MFS and abnormal cranial dura. Patient 2 had severe early onset MFS and an abnormal skull. Patients 3 and 4 had probable Furlong syndrome (FS). Patient 5 had marfanoid (MD) features, mental retardation (MR), and a deletion of chromosome 15q21.1q21.3. All patients had a condition within the MFS, MD-craniosynostosis (CS) or MD-MR spectrum. The names of these entities may become redundant, and instead, come to be considered within the spectrum of TGF-beta signaling pathway disorders. Two recurrent heterozygous FBN1 mutations were found in Patients 1 and 2, and an identical novel heterozygous de novo TGFBR1 mutation was found in Patients 3 and 4, in whom altered fibrillin-1 processing was demonstrated previously [Milewicz et al. (2000); Am J Hum Genet 67:279]. A heterozygous FBN1 deletion was found in Patient 5. These findings support the notion that perturbation of extracellular matrix homeostasis and/or remodeling caused by abnormal TGF-beta signaling is the core pathogenetic mechanism in MFS and related entities including the MD-CS syndromes.