ABSTRACT
An estimated birth prevalence of 1:125,000 is reported in the literature.
Birth to first months of life; fully visible phenotype during childhood.
• Hypertrichosis of the arms and back (75%) (Figure 20.1)
• Capillary hemangiomas on the forehead, nape and lumbar region (60%)
• Simian crease and abnormal dermatoglyphics (50%) (Figure 20.2)
• Increased tendency to form keloids (5%–22%) (Figure 20.3)
• Supernumerary nipples (16%) • Racquet nails • Thick and highly arched eyebrows • Unusually long eyelashes • Atopy keratosis pilaris and ulerythema
ophryogenes • Piebaldism • Multiple pilomatricomas (Figure 20.3) • Epidermal nevi and nevus flammeus in 20% of
patients
• Characteristic broad thumbs and great toes (Figure 20.2)
• Broad terminal phalanges in the other fingers (Figure 20.2)
• Clinodactyly of the fourth toe and of the fourth and fifth fingers
• Distinctive facies consisting of microcephaly, prominent forehead, beaked nose with nasal septum below the alae, deformed ears, higharched palate and irregular and crowded teeth (Figure 20.4)
• Ocular abnormalities include strabismus, cataracts, glaucoma, blepharoptosis, refractive errors, colobomata, nasolacrimal duct obstruction, and anterior segment dysgenesis
• Hearing loss • Short stature with bony abnormalities of the
ribs, vertebrae, and sternum; obesity • Cryptorchidism • Cardiac abnormalities; septa; heart defects (30%) • Severe mental and motor retardation • Report of increased incidence of polyhydram-
nios during pregnancy and increased risk of gestational hypertension in pregnancyies of children with EP300 mutations
• Increased tumor risk
• Complete radiographic studies of bones • Electrocardiography and electroencepha lo graphy
• Autosomal dominant inheritance. • Pathogenic variants of the CREBBP gene were
identified in 50%–70% of RSTS individuals (RSTS1), whereas mutations in the EP300 gene have been reported in about 5%–8% RSTS patients (RSTS2). These genes are involved in multiple
cell pathways of growth control, DNA repair, differentiation, apoptosis, and tumor suppression.
