Lacrimal drainage anomalies in Rubinstein-Taybi syndrome: case report and review of literature

The functional secondary effect after an integrated rehabilitative intervention to learn reading and writing in a girl with Rubinstein-Taybi syndrome

PURPOSE

A case report of a six-year and five-month-old female admitted with typical symptoms of Rubinstein-Taybi syndrome is presented. Clinical and rehabilitation settings where she acquired her reading, writing, and communication skills are described.

METHODS

Because of her cognitive disabilities, a multidisciplinary and long-term intervention (2014-2020) was necessary. Treatment included orthoptic, psychomotor, logopedic, occupational, and neuropsychological care. Her family and school were involved.

RESULTS

Increased attention led to decreased dysfunctional behaviors. Test results are still below average, but there has been significant improvement. Better communication skills resulted from increased phonetic range, improved articulation, lexical-semantic structure, comprehension, and production of sentences. Digital technologies played a significant role in enhancing her communication skills, not just in social interactions but also in school activities. The patient is oriented in time and space with the help of agendas and calendars. She can express her needs and compose concise narratives. As a result of acquiring functional skills, she is better equipped to handle real-life situations, which has led to increased social and family activities.

CONCLUSION

This case report highlights the importance of personalized rehabilitation programs. Obtaining an early genetic diagnosis is crucial for timely tailored rehabilitation, and any delays in this process can hinder progress.

Diagnosis and management in Rubinstein-Taybi syndrome: first international consensus statement

Rubinstein-Taybi syndrome (RTS) is an archetypical genetic syndrome that is characterised by intellectual disability, well-defined facial features, distal limb anomalies and atypical growth, among numerous other signs and symptoms. It is caused by variants in either of two genes (CREBBP, EP300) which encode for the proteins CBP and p300, which both have a function in transcription regulation and histone acetylation. As a group of international experts and national support groups dedicated to the syndrome, we realised that marked heterogeneity currently exists in clinical and molecular diagnostic approaches and care practices in various parts of the world. Here, we outline a series of recommendations that document the consensus of a group of international experts on clinical diagnostic criteria for types of RTS (RTS1: CREBBP; RTS2: EP300), molecular investigations, long-term management of various particular physical and behavioural issues and care planning. The recommendations as presented here will need to be evaluated for improvements to allow for continued optimisation of diagnostics and care.

Genotype-phenotype analysis of ocular findings in Rubinstein-Taybi syndrome - A case report and review of literature

BACKGROUND

Rubinstein-Taybi syndrome (RSTS) is a rare genetic syndrome with a wide range of phenotypic presentations, including characteristic facial features. A variety of ocular abnormalities have been described in patients with RSTS. The genetic etiology of RSTS is heterogeneous but often involves two major genes, CREBBP (cAMP-response element binding protein-binding protein) and EP300 (E1A binding protein p300), with CREBBP variants responsible for the majority of the cases.

MATERIALS AND METHODS

We report a new case of female patient with a novel variant in CREBBP (c.4495C>G), with clinical features consistent with RSTS. We performed a literature review to search for possible genotype-phenotype relationships between the type of variant in CREBBP and frequency of ocular presentations. A PubMed search generated 12 articles that met our inclusion criteria. With the addition of our patient, there were a total of 163 patients included for mutation analysis (164 variants given one patient had two different variants).

RESULTS

Our review revealed that the most common variant types were frameshift (25%), gross deletion (23%), nonsense (18%), and intragenic deletions (13%). There does not appear to be an obvious hot spot location. A total of 127 patients were included for genotype-phenotype analysis of ocular features (36 patients were excluded as unable to discern variant type). The most frequent ocular features in patients with RSTS were down-slanting palpebral fissure (74%), arched eyebrows (56%), long eyelashes (52%), and strabismus (23%).

CONCLUSIONS

Our results suggest that currently there is no clear genotype-phenotype relationship between the type of variant and frequency of associated ocular features in RSTS patients.

Rubinstein-Taybi Syndrome: A Model of Epigenetic Disorder

The Rubinstein-Taybi syndrome (RSTS) is a rare congenital developmental disorder characterized by a typical facial dysmorphism, distal limb abnormalities, intellectual disability, and many additional phenotypical features. It occurs at between 1/100,000 and 1/125,000 births. Two genes are currently known to cause RSTS, CREBBP and EP300, mutated in around 55% and 8% of clinically diagnosed cases, respectively. To date, 500 pathogenic variants have been reported for the CREBBP gene and 118 for EP300. These two genes encode paralogs acting as lysine acetyltransferase involved in transcriptional regulation and chromatin remodeling with a key role in neuronal plasticity and cognition. Because of the clinical heterogeneity of this syndrome ranging from the typical clinical diagnosis to features overlapping with other Mendelian disorders of the epigenetic machinery, phenotype/genotype correlations remain difficult to establish. In this context, the deciphering of the patho-physiological process underlying these diseases and the definition of a specific episignature will likely improve the diagnostic efficiency but also open novel therapeutic perspectives. This review summarizes the current clinical and molecular knowledge and highlights the epigenetic regulation of RSTS as a model of chromatinopathy.

Updates on congenital lacrimal drainage anomalies and their association with syndromes and systemic disorders: A major review

BACKGROUND

To review and update the syndromic and non-syndromic systemic associations of congenital lacrimal drainage anomalies.

METHODS

The authors performed a PubMed search of all articles published in English on congenital lacrimal drainage anomalies (CLDA). The current review provides an update from January 2017 to August 2020 on all CLDA associated with clinical syndromes or non-syndromic systemic disorders. The update intends to appraise the readers on all papers that were published in the interim 3-year period since the publication of the previous major review by authors (1933-2016). Patients with specific syndromes or systemic disorders were then reviewed. Pertinent cross-references from each of the short-listed articles were also included. Data reviewed include syndromic descriptions, systemic details, demographics, lacrimal presentations, management, and outcomes.

RESULTS

There have been significant new updates. Eleven new syndromes have been added to the list of syndromic associations, of which three were suspects. Among the new syndromic associations, three (PHACE, Williams-Beuren, and Peter's plus syndromes) described CLDA details in depth. Several new non-syndromic systemic conditions with associated CLDA also came to light, the foremost amongst them being proboscis lateralis, diprosopus dirrhinus, cerebral palsy, and NGLY-1 related disorders. Although familial presentations have been reported, the inheritance patterns are unclear for most anomalies. Surgical challenges in these patients are distinct, and a thorough pre-operative assessment, including detailed imaging when indicated, may facilitate good outcomes. Two updated tables reflecting the summary of syndromic and non-syndromic systemic associations are provided to capture the details at a glance.

CONCLUSION

It is not very uncommon to find CLDA in syndromic or non-syndromic systemic disorders. Diagnosis of a craniofacial syndrome should prompt the physician to look out for CLDA. Similarly, a diagnosis of multiple CLDA should alert the examiner for the possible presence of associated systemic anomalies.