Introduction
Spinal Muscular Atrophy is a rare neuromuscular disorder caused by
autosomic recessive mutations in the Survival Motor Neuron 1 (SMN1)
gene. According to age of onset and clinical severity, SMA is associated
with different pediatric forms, among them type 1 and 2 are the most
severe ones [1]. The weakness classically also involves the
respiratory muscles with a typical diaphragmatic breathing pattern, most
obvious in type 1 infants with subsequent need for mechanical
ventilation support, recurrent hospitalization and, before treatment
became available, premature exitus [2, 3].
The advent of new therapies increasing SMN protein either by gene
replacement or incrementing SMN2 mRNA splicing, has produced a dramatic
change in progression of the disease, improvement in survival, motor and
respiratory function, more obvious in type 1 infants, who, until the
advent of therapy, rarely survived beyond the 2nd year and never
achieved independent sitting [4, 5, 6].
With increased survival it has become even more important to follow
these patients over time. According to the SMA International
Standard-of-Care (SoC), the assessments should be repeated every 3 to 6
months, involving a multidisciplinary team of specialists at tertiary
centers for neuromuscular diseases, for routine in-personassessment and bed-side physical evaluations [2, 3].
Unfortunately, as a result of Covid-19 pandemic, the physical access to
care, as well as our chance to guarantee the SoC, became more difficult
since many tertiary centers had to limit routine in-person evaluation,
focus resources and reduce the risk of infection. In order to address
some of the difficulties faced by families to attend routine
assessments, we first developed a “contactless ” patient
video-monitoring platform [7] to assure a safe, privacy compliant
and reliable access to specialists while providing, through
questionnaires and tutorials, some essential care, including
rehabilitation, that could not be otherwise guaranteed during the
pandemic. While the platform proved to be extremely useful to replace
some of the routine follow up assessments, SMA families were still very
concerned about the difficulties experienced in getting physical
examinations during acute events. Several parents reported that in the
last few months “red flags” of respiratory infections, happened to go
unnoticed or underestimated by themselves or local practitioners, who
had little experience with neuromuscular diseases. In some cases that
led to preventable complications which could have been avoided. In
others, the absence of reliable assessment, parents rushed their
children to emergency rooms even if this was often not necessary. And
they were worried it may happen again.
We therefore decided to move beyond the video-monitoring solution to
explore the feasibility of an innovative home-basedadvanced-telemedicine platform to perform challenging remote
physical evaluation in type 1 and 2 SMA patients. Although there are
many commercially available tools that could have been theoretically
used to perform remote physical evaluation, there were however some
concerns related to their applicability to type1 and 2 SMA patients. The
concerns were related to the chest and trunk appearance of the SMA
patients as most children present with kyphoscoliosis and thoracic
asymmetry, ribs crowding, thoracic organ displacement (Fig. 1), that are
often associated with pulmonary functional impairment and impaired
airway clearance [8, 9, 10]. This has become particularly true in
type 1 infants who now generally survive beyond the first year but
despite the functional improvements, still have variable degree of trunk
hypotonia and weakness causing kyphoscoliosis that has become one of the
key features of the emerging post treatment new phenotypes.
Because of these concerns, we aimed to explore the feasibility of one of
the advanced telemedicine platforms and explore its possible application
into a clinical SMA setting.
More specifically, we wished to explore feasibility, accuracy, and
experience with home-based virtual physical evaluation, especially
focused on challenging lung auscultation, versus traditional bed-side
exam in type 1 and 2 SMA children with different degrees of scoliosis
and chest asymmetry. Our expectation is to find an innovative solution
to guarantee safety and access to care, reduce infection exposure,
logistic and economic burden for families and improve disease
management, during Covid-19 and beyond.