A syndrome characterised by:¹

• Facial abnormalities
• Broad thumbs
• Broad great toes
• Short stature
• Mental retardation

It was first described in 1963 by Rubinstein and Taybi.² More recently, mutations in two genes - CREBBP and EP300 - have been identified to cause the syndrome.

Epidemiology

• Incidence is about 1 case per 100,000 live births.³
• Most cases of Rubinstein-Taybi syndrome are sporadic, although the syndrome has been reported in monozygotic twins.⁴

Presentation

• Facial abnormalities: hypoplastic maxilla with a narrow palate, prominent beaked nose, antimongoloid eye slant, low-set/malformed ears, and strabismus.
• Digital abnormalities: broad thumbs, fingers and great toes.
• Abnormalities of growth and development: severe mental retardation, sleep apnoea, speech difficulties, hypotonia, and growth restriction.
• Skeletal abnormalities: patellar dislocation.
• Skin: hirsutism, capillary naevus of the forehead.
• Cardiovascular abnormalities, including ventricular septal defects, and patent ductus arteriosus.⁵
• Ocular abnormalities occur in the majority of patients. The abnormalities are diverse but include retinal dysfunction, which has been reported to occur in 78% of patients.⁶
• Cryptorchidism in males.
• Mood disorders and obsessive-compulsive disorder.
• Recurrent respiratory tract infections.⁷

Differential diagnosis

Other similar syndromes to consider are:¹

• Faciodigitogenital syndrome
• Greig's syndrome
• Larsen's syndrome
• Pfeiffer's syndrome
• Saethre-Chotzen syndrome
• Simpson-Golabi-Behmel syndrome
• Weaver's syndrome

Investigations

Chromosome karyotype analysis shows the presence of structural abnormalities and confirms the diagnosis. Fluorescence in situ hybridisation can detect microdeletions of the CBP gene on band 16p13.
Otherwise, investigations will depend on the clinical manifestations of the patient:

• Skeletal deformities may require CT and MRI scans as well as X-rays.
• Cardiac assessment, including echocardiography, for congenital heart disease.
• Eye and vision assessment for ocular abnormalities.
• Ear, nose and throat, and hearing assessment.

Management

• The wide spectrum of clinical manifestations requires disease management tailored to the problems of each patient.
• Physiotherapy, speech therapy and special education are all required.
• Families of affected children need a great deal of support and all management intervention must be carefully co-ordinated and periodically reviewed.

Prognosis

• The survival rate is good, with frequent reports of survival to adulthood.
• Affected children suffer from developmental delay, growth restriction and feeding difficulties.
• Respiratory tract infections and complications from congenital heart disease are primary causes of morbidity and mortality in infancy.¹

Document references

1. Mijuskovic ZP et al; Rubinstein-Taybi Syndrome, eMedicine, Feb 2009
2. Rubinstein JH, Taybi H; Broad thumbs and toes and facial abnormalities. Am J Dis Child 1963; 105: 588-608.
3. Roelfsema JH, Peters DJ; Rubinstein-Taybi syndrome: clinical and molecular overview. Expert Rev Mol Med. 2007 Aug 20;9(23):1-16. [abstract]
4. Baraitser M, Preece MA; The Rubinstein-Taybi syndrome: occurrence in two sets of identical twins. Clin Genet. 1983 Apr;23(4):318-20.
5. Stevens CA, Bhakta MG; Cardiac abnormalities in the Rubinstein-Taybi syndrome. Am J Med Genet. 1995 Nov 20;59(3):346-8. [abstract]
6. van Genderen MM, Kinds GF, Riemslag FC, et al; Ocular features in Rubinstein-Taybi syndrome: investigation of 24 patients and review of the literature. Br J Ophthalmol. 2000 Oct;84(10):1177-84. [abstract]
7. Naimi DR, Munoz J, Rubinstein J, et al; Rubinstein-Taybi syndrome: an immune deficiency as a cause for recurrent infections. Allergy Asthma Proc. 2006 May-Jun;27(3):281-4. [abstract]

Internet and further reading

• Rubinstein-Taybi Syndrome, MedlinePlus
• Rubinstein-Taybi syndrome, Online Mendelian Inheritance in Man (OMIM)

Acknowledgements