A pilot study for evaluation of hypotonia in children with neurofibromatosis type 1

The management of neurofibromatosis type 1 (NF1) in children and adolescents

INTRODUCTION

Neurofibromatosis type 1 (NF1) is a rare neurogenetic disorder characterized by multiple organ system involvement and a predisposition to benign and malignant tumor development. With revised NF1 clinical criteria and the availability of germline genetic testing, there is now an opportunity to render an early diagnosis, expedite medical surveillance, and initiate treatment in a prompt and targeted manner.

AREAS COVERED

The authors review the spectrum of medical problems associated with NF1, focusing specifically on children and young adults. The age-dependent appearance of NF1-associated features is highlighted, and the currently accepted medical treatments are discussed. Additionally, future directions for optimizing the care of this unique population of children are outlined.

EXPERT OPINION

The appearance of NF1-related medical problems is age dependent, requiring surveillance for those features most likely to occur at any given age during childhood. As such, we advocate a life stage-focused screening approach beginning in infancy and continuing through the transition to adult care. With early detection, it becomes possible to promptly institute therapies and reduce patient morbidity. Importantly, with continued advancement in our understanding of disease pathogenesis, future improvements in the care of children with NF1 might incorporate improved risk assessments and more personalized molecularly targeted treatments.

Identifying and Evaluating Young Children with Developmental Central Hypotonia: An Overview of Systematic Reviews and Tools

Children with developmental central hypotonia have reduced muscle tone secondary to non-progressive damage to the brain or brainstem. Children may have transient delays, mild or global functional impairments, and the lack of a clear understanding of this diagnosis makes evaluating appropriate interventions challenging. This overview aimed to systematically describe the best available evidence for tools to identify and evaluate children with developmental central hypotonia aged 2 months to 6 years. A systematic review of systematic reviews or syntheses was conducted with electronic searches in PubMed, Medline, CINAHL, Scopus, Cochrane Database of Systematic Reviews, Google Scholar, and PEDro and supplemented with hand-searching. Methodological quality and risk-of-bias were evaluated, and included reviews and tools were compared and contrasted. Three systematic reviews, an evidence-based clinical assessment algorithm, three measurement protocols, and two additional measurement tools were identified. For children aged 2 months to 2 years, the Hammersmith Infant Neurological Examination has the strongest measurement properties and contains a subset of items that may be useful for quantifying the severity of hypotonia. For children aged 2-6 years, a clinical algorithm and individual tools provide guidance. Further research is required to develop and validate all evaluative tools for children with developmental central hypotonia.

Hypotonia: Is It a Clear Term and an Objective Diagnosis? An Exploratory Systematic Review

BACKGROUND

Hypotonia is considered a determinant factor in multiple developmental disorders and is associated with various characteristics and morbidities. It is necessary to perform a systematic review to know which characteristics are described as associated with hypotonia in children and which methods are used for its diagnosis.

METHODS

Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were used to develop the systematic review protocol. A search of databases (Pubmed, Cochrane, Web of Knowledge, among others) was performed in May 2021 to identify relevant studies. Those describing characteristics or tests of hypotonia assessment were included, excluding those that exclusively addressed peripheral hypotonia. Two reviewers evaluated the articles and collected the data in a table, noting the authors, date of publication, type of study, and characteristics or tests described in relation to hypotonia. The quality of the studies was also assessed, and data were extracted.

RESULTS

A total of 8778 studies were identified and analyzed, of which 45 met the inclusion criteria. Fifty-three characteristics associated with hypotonia and tests used for its evaluation were located, with pull to sit and vertical suspension being the most frequently referenced.

CONCLUSIONS

The characteristics associated with hypotonia, more highly debated by authors are muscle strength, hypermobility, or the maintenance of antigravity postures. The most used test in the diagnosis of hypotonia is observation, followed by the pull-to-sit test, and adoption of frog posture. A unanimous understanding of the term hypotonia would favor further research.

Clinical evaluation of muscle functions in neurofibromatosis type 1

AIM

Muscle weakness, fatigue and speech problems can occur in neurofibromatosis type 1 (NF1). The pathogenesis of these symptoms is unclear, likely multifactorial. We examined motor function in limb and speech muscles in NF1 patients.

METHODS

We evaluated NF1 and control groups aged 4-18 years for muscle strength, tone and mobility using standard manual testing, joint motion and Beighton score measurements. Speech and language functions were assessed by speech articulation and resonance. As a marker of muscle tissue turnover, we determined collagen degradation products in urine before and after submaximal exercise.

RESULTS

NF1 patients had reduced strength in proximal limb muscles compared to control subjects. Speech articulation problems and hypernasality were more common in NF1 (47% and 38%, respectively). Collagen products excreted in urine correlated with gluteal and biceps muscle strength.

CONCLUSION

Muscle dysfunction can be detected in some children with NF1 and may explain certain clinical features including fatigue, speech and articulation problems. If confirmed by further research, these findings may be relevant to the management of this condition.

AGREE-II Appraisal of a clinical algorithm for hypotonia assessment

Objective

The objective of this study was to systematically appraise the quality of an evidenced-based clinical algorithm for the clinical assessment of hypotonia in children.

Design

The Appraisal of Guidelines for Research and Evaluation (AGREE) II tool with 23 items and six domains was used. The study was located in South Africa. Ten appraisers, who were recruited based on specific selection criteria, completed the assessment.

Results

Nine appraisers recommended the EBCA without any modification. Scope and purpose (94%), stakeholder involvement (91%) and editorial independence (99%) were rated the highest with the lower scoring domains being clarity of presentation (85%) and applicability (86%) due to clarity required in areas of resource implications and auditing and monitoring criteria. Inter-rater reliability was strong (ICC 0.7) amongst the appraisers in this study.

Conclusion

This is the first independent assessment of the methodological rigour and transparency of a clinical algorithm using the AGREE-II instrument. Determining the quality of the EBCA for practice is essential as this would ultimately aid clinicians towards more accurate clinical assessment of hypotonia which would inevitably impact outcomes and management of the child presenting with this symptom. Whilst the AGREE-II provided initial feedback on the methodological rigour of development, understanding that the AGREE-II instrument evaluates the guideline development process and not the content is also essential in order to consider the next stage which would be to consider clinicians feedback on the clinical utility of this EBCA.

Evidence-Based Clinical Algorithm for Hypotonia Assessment: To Pardon the Errs

Despite the many advances in diagnostics, the clinical assessment of children with hypotonia presents a diagnostic challenge for clinicians due to the current subjectivity of the initial clinical assessment. The aim of this paper is to report on an evidence-based clinical algorithm (EBCA) that was developed for the clinical assessment of hypotonia in children as part of the output of a multiphased study towards assisting clinicians in more accurate assessments. This study formed part of a larger advanced mixed methods design. The preceding phases of the study included a systematic review, a survey amongst clinicians, a consensus process (Delphi technique), and a qualitative critique with multiple focus groups. Samples were drawn from three professional groups (occupational therapists, physiotherapists, and paediatricians). Data were analysed at each stage and merged in the development of the EBCA. The EBCA followed a rigorous process of development and critique. The methods for formulating changes in the revision and development of the EBCA are presented together with a description and presentation of the final algorithm for practice. The overarching concepts that guided the development and refinement of the EBCA are described, taking into consideration knowledge translation, evidence-based practice, and the value of EBCAs in addition to recommendations for stakeholder uptake. The EBCA is envisaged to be useful in practice for clinicians who are faced with the assessment of a child that is suspected as having hypotonia via a systematic process in identifying specific characteristics that are associated with low muscle tone.

'Toning' up hypotonia assessment: A proposal and critique

Background

Clinical assessment of hypotonia is challenging due to the subjective nature of the initial clinical evaluation. This poses dilemmas for practitioners in gaining accuracy, given that the presentation of hypotonia can be either a non-threatening or malevolent sign. The research question posed was how clinical assessment can be improved, given the current contentions expressed in the scientific literature.

Objectives

This paper describes the development and critique of a clinical algorithm to aid the assessment of hypotonia.

Methods

An initial exploratory sequential phase, consisting of a systematic review, a survey amongst clinicians and a Delphi process, assisted in the development of the algorithm, which is presented within the framework of the International Classification of Functioning, Disability and Health. The ensuing critique followed a qualitative emergent–systematic focus group design with a purposive sample of 59 clinicians. Data were analysed using semantical content analysis and are presented thematically with analytical considerations.

Results

This study culminated in the development of an evidence-based clinical algorithm for practice. The qualitative critique of the algorithm considered aspects such as inadequacies, misconceptions and omissions; strengths; clinical use; resource implications; and recommendations.

Conclusions

The first prototype and critique of a clinical algorithm to assist the clinical assessment of hypotonia in children has been described. Barriers highlighted include aspects related to knowledge gaps of clinicians, issues around user-friendliness and formatting concerns. Strengths identified by the critique included aspects related to the evidence-based nature of the criteria within the algorithm, the suitability of the algorithm in being merged or extending current practice, the potential of the algorithm in aiding more accurate decision-making, the suitability of the algorithm across age groups and the logical flow. These findings provide a starting point towards ascertaining the clinical utility of the algorithm as an essential step towards evidence-based praxis.