Rubinstein-Taybi syndrome: Clinical profile of 11 patients and review of literature

Abstract

Background: Rubinstein-Taybi syndrome (RSTS) is a rare congenital neurodevelopmental disorder, characterized by postnatal growth deficiency, typical dysmorphic features, broad thumbs and toes, and mental retardation. Very few cases are reported in literature from developing countries. Diagnosis is often delayed due to non-familiarity with the characteristic features of this syndrome.

Aims: To report 11 cases of RSTS and to review the current literature.

Settings and design: Retrospective study conducted in genetic and metabolic unit of a tertiary care teaching hospital in north India over a period of 3½ years.

Materials and methods: 11 patients with diagnosis of RSTS were identified, and their case sheets were reviewed.

Results: Developmental delay was presenting complaint in 10 patients, and seizure in 1 case. 7 patients had microcephaly (head circumference below -3 SD), and a prominent beaked nose was seen in 9 patients. The intelligence quotient (IQ) varied from 22-62 in 7 patients who had mental retardation. The most notable features in hands were broadness, shortening, and flattening of the distal phalanx of thumbs or great toes. Additionally, we also noted webbing of neck, microphthalmia, and pachygyria (on MRI brain) in 1 patient each.

Conclusions: The diagnosis of RSTS is primarily clinical and based on characteristic phenotype that is often combined with a variety of somatic anomalies. An early diagnosis facilitates appropriate genetic counseling and in planning the management.

Keywords: Beaked nose; broad thumbs; broad toes; dysmorphism; mental retardation.

Figure 1

(a) Showing broad thumbs, (b) X-ray of hands of another patient showing broad and radially- deviated thumbs

Figure 2

(a-c) Characteristic facial profile of two patients