Management of nutritional and gastrointestinal issues in RASopathies: A narrative review

Clarifying main nutritional aspects and resting energy expenditure in children with Smith-Magenis syndrome

Our study aims to define resting energy expenditure (REE) and describe the main nutritional patterns in a single-center cohort of children with Smith-Magenis syndrome (SMS). REE was calculated using indirect calorimetry. Patients' metabolic status was assessed by comparing measured REE (mREE) with predictive REE (pREE). Patients also underwent multidisciplinary evaluation, anthropometric measurements and an assessment of average energy intake, using a 3-day food diary, which was reviewed by a specialized dietitian. Twenty-four patients (13 M) were included, the median age was 9 years (IC 95%, 6-14 years), 84% had 17p11.2 deletion, and 16% had RAI1 variants. REE was not reduced in SMS pediatric patients, and the mREE did not differ from the pREE. In patients with RAI1 variants (16%, n = 3/24), obesity was more prevalent than those with 17p11.2 deletion (100% vs 38%). Lower proteins intake and higher total energy intake were reported in obese and overweight patients, compared to healthy weight children. No significant difference was found between males and females in energy or macronutrient intake.

CONCLUSIONS

In SMS, the onset of obesity is not explained by REE abnormalities, but dietary factors seem to be crucial. Greater concern should be addressed to patients with RAI1 variants. A better understanding of the molecular mechanisms causing obesity in SMS patients could set the basis for possible future targeted therapies.

WHAT IS KNOWN

• More than 90% of SMS patients after the age of 10 are overweight or obese.

WHAT IS NEW

• Onset of overweight and obesity in SMS pediatric patients is not explained by abnormal resting energy expenditure. • The development of syndrome-specific dietary guidelines for SMS patients should be of utmost relevance and are highly needed.

Validation and cross-cultural adaptation of the Italian version of the paediatric eating assessment tool (I-PEDI-EAT-10) in genetic syndromes

BACKGROUND

The Pediatric Eating Assessment Tool (PEDI-EAT-10) is a reliable and valid tool for rapid identification of dysphagia in patients aged 18 months to 18 years.

AIMS

To translate and adapt the PEDI-EAT-10 into the Italian language and evaluate its validity and reliability.

METHODS & PROCEDURES

The translation and cross-cultural adaptation of the tool consisted of five stages: initial translation, synthesis of the translations, back translation, expert committee evaluation and test of the prefinal version. The internal consistency of the translated tool was analysed in a clinical group composed of 200 patients with special healthcare needs aged between 18 months and 18 years. They were consecutively enrolled at the Rare Disease Unit, Paediatrics Department, Fondazione Policlinico Agostino Gemelli-IRCCS, Rome. For test-retest reliability, 50 caregivers filled in the PEDI-EAT-10 questionnaire for a second time after a 2-week period. Construct validity was established by comparing data obtained from patients with data from healthy participants (n = 200). The study was approved by the local ethics committee.

OUTCOMES & RESULTS

Psychometric data obtained from patients (104 M; mean age = 8.08 ± 4.85 years; median age = 7 years) showed satisfactory internal consistency (Cronbach's α = 0.89) and test-retest reliability (Pearson r = 0.99; Spearman r = 0.96). A total of 30% of children were classified as having a high risk of penetration/aspiration. The Italian PEDI-EAT-10 mean total score of the clinical group was significantly different from that resulting from healthy participants.

CONCLUSIONS & IMPLICATIONS

The PEDI-EAT-10 was successfully translated into Italian, validated and found to be a reliable one-page rapid screening tool to identify dysphagia in children and adolescents with special needs.

WHAT THIS PAPER ADDS

What is already known on the subject The PEDI-EAT-10 is a valid and reliable quick discriminative paediatric tool for identifying penetration/aspiration risks. What this paper adds to the existing knowledge In the present study we successfully translated and adapted the PEDI-EAT-10 into the Italian language. What are the potential or actual clinical implications of this work? This translation and adaptation increase access to valid feeding and swallowing assessment for children of Italian-speaking families. In addition, the I-PEDI-EAT-10 can suggest further assessment of patients' swallowing abilities.

The Cardiofaciocutaneous Syndrome: From Genetics to Prognostic-Therapeutic Implications

Cardiofaciocutaneous (CFC) syndrome is one of the rarest RASopathies characterized by multiple congenital ectodermal, cardiac and craniofacial abnormalities with a mild to severe ocular, gastrointestinal and neurological involvement. It is an autosomal dominant syndrome, with complete penetrance, caused by heterozygous pathogenic variants in the genes BRAF, MAP2K1/MEK1, MAP2K2/MEK2, KRAS or, rarely, YWHAZ, all part of the RAS-MAPK pathway. This pathway is a signal transduction cascade that plays a crucial role in normal cellular processes such as cell growth, proliferation, differentiation, survival, metabolism and migration. CFC syndrome overlaps with Noonan syndrome, Costello syndrome, neurofibromatosis type 1 and Legius syndrome, therefore making the diagnosis challenging. Neurological involvement in CFC is more severe than in other RASopathies. Phenotypic variability in CFC patients is related to the specific gene affected, without a recognized genotype-phenotype correlation for distinct pathogenic variants. Currently, there is no specific treatment for CFC syndrome. Encouraging zebrafish model system studies suggested that, in the future, MEK inhibitors could be a suitable treatment of progressive phenotypes of CFC in children. A multidisciplinary care is necessary for appropriate medical management.

From Feeding Challenges to Oral-Motor Dyspraxia: A Comprehensive Description of 10 New Cases with CTNNB1 Syndrome

CTNNB1 syndrome is an autosomal-dominant neurodevelopmental disorder featuring developmental delay; intellectual disability; behavioral disturbances; movement disorders; visual defects; and subtle facial features caused by de novo loss-of-function variants in the CTNNB1 gene. Due to paucity of data, this study intends to describe feeding issues and oral-motor dyspraxia in an unselected cohort of 10 patients with a confirmed molecular diagnosis. Pathogenic variants along with key information regarding oral-motor features were collected. Sialorrhea was quantified using the Drooling Quotient 5. Feeding abilities were screened using the Italian version of the Montreal Children's Hospital Feeding Scale (I-MCH-FS). Mild-to-severe coordination difficulties in single or in a sequence of movements involving the endo-oral and peri-oral muscles were noticed across the entire cohort. Mild-to-profuse drooling was a commonly complained-about issue by 30% of parents. The mean total I-MCH-FS t-score equivalent was 43.1 ± 7.5. These findings contribute to the understanding of the CTNNB1 syndrome highlighting the oral motor phenotype, and correlating specific gene variants with clinical characteristics.

The "FEEDS (FEeding Eating Deglutition Skills)" over Time Study in Cardiofaciocutaneous Syndrome

Feeding, eating and deglutition difficulties are key concerns in patients with cardiofaciocutaneous syndrome (CFCS). This study intends to quantify the development of feeding skills from birth to adulthood in patients with CFCS. Twenty-seven patients (eight males; mean age: 16.7 ± 8.3 years; median age: 15 years, age range: 1.5-38 years) with molecularly confirmed clinical diagnosis of CFCS were prospectively recruited from the Rare Disease Unit, Paediatrics Department, Fondazione Policlinico Agostino Gemelli-IRCCS, Rome, Italy, over a one-year period. Pathogenic variants along with key information regarding oro-motor features were collected. Sialorrhea was quantified using the Drooling Quotient 5. Feeding abilities were screened using the Italian version of the Montreal Children's Hospital Feeding Scale (I-MCH-FS). The oral sensory processing section of the Sensory Profile completed the assessment. Mild-to-profuse drooling was experienced by 25% of patients, and food taste selectivity was a constant during infancy (65%), with persistence even beyond adolescence. Nineteen percent of participants with long-term enteral feeding dependency had BRAF, KRAS and MAP2K1 mutations. These findings document that mealtime challenges in CFCS do not remain restricted only to the paediatric age, and that supportive care until adulthood plays a key role.

The Impact of Blenderized Tube Feeding on Gastrointestinal Symptoms, a Scoping Review

Severe gastrointestinal symptoms are one of the main reasons for switching from conventional artificial tube feeding to blenderized tube feeding (BTF). This study aimed to describe and quantify the impact of BTF on gastrointestinal symptoms in children and adults. We analyzed four databases (PubMed, Scopus, Cochrane Library, and Google Scholar). The review was performed following the PRISMA extension for Scoping Reviews checklist. The methodological quality of articles was assessed following the NIH quality assessment tools. The initial search yielded 535 articles and, after removing duplicates and off-topic articles, 12 met the inclusion criteria. All included papers unanimously converged in defining an improvement of gastrointestinal symptoms during blenderized feeding: the eight studies involving pediatric cohorts report a decrease from 30 to over 50% in gagging and retching after commencing BTF. Similar rates are reported for constipation and diarrhea improvement in most critically ill adults. Experimental studies and particularly randomized controlled trials are needed to develop robust evidence on the effectiveness of BTF in gastrointestinal symptom improvement with prolonged follow-up and adequate medical monitoring.