A new score combining compound muscle action potential (CMAP) amplitudes and motor score is predictive of motor outcome after AVXS-101 (Onasemnogene Abeparvovec) SMA therapy

Spinal muscular atrophy 1 (SMA1) is a severe early genetic disease with degeneration of motor neurons. Motor development is still suboptimal after gene replacement therapy in symptomatic patients. In this study, compound muscle action potential (CMAP) amplitudes were explored as predictors of motor recovery after gene therapy. Thirteen symptomatic SMA1 patients were prospectively included at the Necker Enfants Malades Hospital, Paris, France (Cohort 1) and 12 at the other pediatric neuromuscular reference centers of the French Filnemus network (Cohort 2). In Cohort 1, median CMAP amplitudes showed the best improvement between baseline and the 12 months visit compared to the other tested nerves (ulnar, fibular and tibial). High median CMAP amplitudes at baseline was associated with unaided sitting achievement at M6 (AUC 90%). None of the patients with CHOPINTEND at M0 < 30/64 and median CMAP < 0.5 mV achieved unaided sitting at M6 and this result was confirmed on Cohort 2 used as an independent validation data. Thus, median CMAP amplitude is a valid biomarker for routine practice to predict sitting at M6. A median CMAP amplitude over 0.5 mV at baseline may predict better motor recovery.

State of the art for motor function assessment tools in spinal muscular atrophy (SMA)

Spinal muscular atrophy (SMA) is a progressive disease characterized by a degeneration of the spinal cord motor neurons. Many clinical trials - planned, in progress, or completed - have chosen motor function as the primary or secondary outcome because motor function assessment tools appeared to be more reliable than quantitative muscle testing in monitoring the course of the disease. Reliable, valid, and responsive outcome measures are needed to be able to capture the effectiveness of the therapeutic approach during clinical trials. Medical staff involved in neuromuscular diseases is faced with increasing pressure regarding the complex issue of choosing the right outcome measure for the objectives they have to assess. This paper provides a narrative literature review of available and validated motor function assessment tools in SMA population based on SMA subtypes, age and ambulant status. © 2020 French Society of Pediatrics. Published by Elsevier Masson SAS. All rights reserved.

Construction and feasibility study of the SOFMER Activity Score (SAS), a new assessment of physical and cognitive activity

OBJECTIVES

For hospitalizations in rehabilitation centers (RCs) in France, the quantification of healthcare givers' activity is based on the dependency of the patients, defined as a total or partial inability to perform activities required for daily living without help. The tools currently used to quantify dependency are not sufficiently precise. Here we describe the construction of a new tool, the SOFMER Activity Score (SAS scoring), which allows for a good description of the level of activity of patients hospitalized in RCs, and a feasibility study of the tool.

METHODS

After a study group proposed the first version of the SAS, the validity of its content was studied by the Delphi consensus method: 26 physicians or healthcare professionals known for their expertise in PMR responded to the first round. The feasibility study was prospective and involved multi-site professionals. Data related to the SAS determined by a multidisciplinary team were collected and compared to the Activité de la Vie Quotidienne (AVQ) scale, which is administered to all patients and included in medical and administrative data.

RESULTS

We included 81 patients in the feasibility study. The mean (SD) time to obtain the SAS was 4.5 (3.3) min. For 97.5% of scorings, the participating professionals judged that the SAS was compatible or fairly compatible with clinical practice. The internal structure of the SAS scale seemed better than that of the AVQ scale, for which the present study confirmed a floor effect for all items.

CONCLUSIONS

The SAS allows for measuring the level of physical and cognitive activity of a patient hospitalized in an RC. If validation studies for the SAS, exploring its reliability, construct validity or criterion validity, confirm the tool's good metrological qualities, the SAS will allow for a good quantification of the burden of care.

Perspectives in neonatal and childhood arterial ischemic stroke

INTRODUCTION

Over the last decade considerable advances have been made in the identification, understanding and management of pediatric arterial ischemic stroke. Such increasing knowledge has also brought new perspectives and interrogations in the current acute and rehabilitative care of these patients. Areas covered: In developed countries, focal cerebral arteriopathy is one of the most common causes of arterial ischemic stroke in childhood and imaging features are well characterized. However, there are ongoing debates regarding its underlying mechanisms, natural evolution and proper management. The implementation of thrombolytic therapy in acute pediatric stroke has been shown to be efficient in anecdotal cases but is still limited by a number of caveats, even in large tertiary centers. Finally, neonatal stroke represents a unique circumstance of possible early intervention before the onset of any neurological disability but this appears meaningful only in a selective group of neonates. Expert commentary: While perinatal stroke, a leading cause of cerebral palsy, appears to be multifactorial, a large number of childhood ischemic stroke are probably essentially triggered by infectious factors leading to vessel wall damage. Current research is aiming at better identifying risk factors in both conditions, and to define optimal acute and preventive therapeutic strategies in order to reduce significant long-term morbidity.

[Vitamin D supplementation: not too much, not too little!]

Vitamin D deficiency is common in the general population and even more frequent in patients with chronic diseases. The prevention of rickets with native vitamin D supplementation is one of the oldest and most effective prophylactic measures ever reported in medicine, leading to an almost complete eradication of vitamin D-deficient rickets in developed countries. We report on two children with vitamin D abnormalities: the first, 10-year-old child developed rickets without any vitamin D supplementation despite different risk factors (autism, ethnicity, nutritional problems, chronic antiepileptic therapies). In contrast, the second, 8-month-old child received double doses of native vitamin D from birth for several months and was referred for acute and symptomatic hypercalcemia. As such, vitamin D supplementation must follow specific rules: neither too much nor too little! We also discuss the emergence of "new" genetic diseases such as mutations in the 24-hydroxylase (CYP24A1) gene inducing neonatal hypercalcemia and nephrocalcinosis: we believe that before prescribing conventional vitamin D supplementation as recommended by the national guidelines, pediatricians should quickly rule out a potential genetic abnormality in phosphate/calcium metabolism (namely a history of lithiasis or hypercalcemia) that would lead to further biological investigations.

Quality of life and functional outcome in early school-aged children after neonatal stroke: a prospective cohort study

BACKGROUND

Quality of life (QoL) is recognized internationally as an efficient tool for evaluating health interventions. To our knowledge, QoL has not been specifically assessed in children after neonatal arterial ischemic stroke (AIS).

AIM

To study the QoL of early school-aged children who suffered from neonatal AIS, and QoL correlation to functional outcome.

METHOD

We conducted a multicenter prospective cohort study as part of a larger study in full-term newborns with symptomatic AIS. Participating families were sent anonymous QoL questionnaires (QUALIN). Functional outcome was measured using the Wee-FIM scale. Healthy controls in the same age range were recruited in public schools. Their primary caregivers filled in the QUALIN questionnaires anonymously. We used Student's t-test and a rank test to compare patients and controls' QoL and functional outcomes.

RESULTS

84 children with neonatal AIS were included. The control group was composed of 74 children, of which ten were later excluded due to chronic conditions. Mean ages and QUALIN median scores did not differ between patients and controls. Median Wee-FIM scores were lower in hemiplegic children than in non-hemiplegic ones (p < 0.001). QoL scores did not seem correlated to functional outcome.

INTERPRETATION

Those results could support the presence of a "disability paradox" in young children following neonatal AIS.

[Multicentric study of medical care and practices in spinal muscular atrophy type 1 over two 10-year periods]

AIM

Questions about care practices and the role of palliative care in pediatric neurodegenerative diseases have led the Neuromuscular Committee of the French Society of Neurology to conduct a retrospective study in spinal muscular atrophy type 1, a genetic disease most often leading to death before the age of 1 year.

MATERIAL AND METHODS

A retrospective multicenter study from pediatricians included in the reference centers of pediatric neuromuscular diseases was carried out on two 10-year periods (1989-1998 and 1999-2009).

RESULTS

The 1989-1998 period included 12 centers with 106 patients, the 1999-2009 period 13 centers with 116 children. The mean age of onset of clinical signs was 2.1 months (range, 0-5.5 months), the median age at diagnosis was 4 months (range, 0-9 months) vs 3 months. The median age of death was 7.5 months (range, 0-24 months) vs 6 months. The care modalities included physiotherapy (90 %), motor support (61 % vs 26 % for the previous period), enteral nutrition by nasogastric tube (52 % vs 24 %), and 3.4 % of children had a gastrostomy (vs 1.8 %). At home, pharyngeal aspiration was used in 64 % (vs 41 %), oxygen therapy in 8 %, noninvasive ventilatory support in 7 %. The mean age at death was 8.1 months (range, 0-24 months) vs 7 months, the time from diagnosis to death was 4 months vs 3 months. Death occurred at home in 23 % vs 17 %, in a pediatric unit in 62 % vs 41 %. The use of analgesics and sedative drugs was reported in 60 % of cases: 40 % morphine (vs 18 %) and benzodiazepines in 48 % (vs 29 %). Respiratory support was limited mostly to oxygen by nasal tube (55 % vs 54 %), noninvasive ventilation in 9 % of the cases, and intubation and assisted mechanical ventilation (2 %).

DISCUSSION AND CONCLUSION

These results confirm a change in practices and the development of palliative care in children with a French consensus of practices quite different from the standard care in North-America and closer to the thinking of English medical teams. A prospective study within the 2011 national hospital clinical research program (PHRC 2011) is beginning in order to evaluate practices and the role of families and caregivers.

Rehabilitation of 190 non-ambulatory children with cerebral palsy in structures of care or in liberal sector

AIMS

To describe the rehabilitation of non-ambulatory children with cerebral palsy and to explore adjustability on their individual needs.

MATERIAL AND METHOD

Data described are extracted from an on-going national cohort study, following during 10years 385 children with cerebral palsy, aged from 4 to 10, Gross Motor Function Classification System IV and V. We analysed data from the first 190 patients (mean age 6years 10months (SD 2.0), 111 boys), focusing on physiotherapy, ergotherapy, psychomotility and speech therapy in medico-social and liberal sectors.

RESULTS

In medico-social sector, duration of paramedical care is significantly more important than in liberal sector (structure of care: median=4.25h/week, liberal sector: median=2.00h/week) (P<0.0001). More than 4 different types of care per week are given in medico-social sector, while in liberal sector children benefit from only 2 different types of care a week. In investigators opinion, rehabilitation in structures of care is 71.65% adapted as opposed to 18.75% in the liberal sector (P<0.001). Children level V have less time of rehabilitation than the others (P=0.0424).

INTERPRETATION

Rehabilitation of children with cerebral palsy who are not able to walk, with an objective to improve quality of life, is truly multidisciplinary and suitable in medico-social sector.

Tolerance and effectiveness on pain control of Pamidronate® intravenous infusions in children with neuromuscular disorders

Osteoporosis is a common complication in children with motor impairments. They have a higher risk of fractures (20% during their lifetime) mostly at femoral level. Furthermore, these children have pain yet no clear relation has been established between osteoporosis and pain. The efficacy of bisphosphonates has been validated in adults and for children with osteogenesis imperfecta (OI). However, its use in children with motor impairments has not yet been validated.

PATIENTS AND METHODS

Retrospective study on the medical charts of children presenting neurological diseases and motor impairments associated to secondary symptomatic osteoporosis. These children underwent treatment with Pamidronate(®) intravenous infusions (I.V.) in Lyon and Valence between 2002 and 2008. Data were collected on pain control, incidence and frequency of fractures and bone mass density (BMD). Data on adverse events were also collected to evaluate treatment's tolerance.

RESULTS

Twelve children's charts were studied for a total of 50 Pamidronate(®) I.V. infusions. Regarding treatment's efficacy, we observed a clear decrease and even total relief of the pain with improvement reported after 98% of perfusions. Regarding BMD, there was a real improvement after the treatment (e.g., lumbar BMD measures, -46.5% before treatment and -27% after treatment). The adverse events, flu-like syndrome, muscle pain and asymptomatic hypocalcemia, were minor and quickly reversible.

CONCLUSION

It seems quite essential to screen for osteoporosis-related pain in these children and treat them quickly to avoid a negative impact on their quality of life. Treatment with I.V. bisphosphonates has shown its relevance, yet practical modalities still need to be defined. It would be interesting but quite difficult to implement, in light of the positive effect of this study, a prospective, randomized, controlled, double-blind vs. placebo study on a large enough sample of patients.