Summary
Pfeiffer syndrome is characterised by the association of craniosynostosis, broad and deviated thumbs and big toes, and partial syndactyly of the fingers and toes. Hydrocephaly may be found occasionally, along with severe ocular proptosis, ankylosed elbows, abnormal viscera, and slow development. The syndrome is rare, affecting about 1 in 100,000 individuals. Pfeiffer syndrome is divided into three clinical subtypes based on the severity of the phenotype. Type 1 "classic'' Pfeiffer syndrome involves individuals with mild manifestations including brachycephaly, midface hypoplasia and finger and toe abnormalities. It is associated with normal intelligence and a generally good outcome. Type 2 involves cloverleaf skull, extreme proptosis, finger and toe abnormalities, elbow ankylosis or synostosis, developmental delay and neurological complications. Type 3 is similar to type 2 but does not involve cloverleaf skull. Clinical overlap between the three types may occur. The disorder is inheritied an autosomal dominant trait and can be caused by mutations in the fibroblast growth factor receptor genes FGFR-1 or FGFR-2. Pfeiffer syndrome can be diagnosed prenatally by sonography showing craniosynostosis, hypertelorism with proptosis and broad thumbs, or molecularly if it concerns a recurrence and the causative mutation was found. Molecular genetic testing is important for confirming the diagnosis. The management includes multi-staged surgery for the craniosynostosis. Midfacial surgery is performed to reduce the exophthalmos and midfacial hypoplasia. *Authors: Drs A. Vogels and J. P. Fryns (June 2006)*. Reproduced from Pfeiffer syndrome. Orphanet J Rare Dis. 2006;1:19.
