Table 2.

Comparison of clinical symptoms at disease onset and current status.

Patient ID	Clinical symptoms	Gross motor/Ambulatory status	Musculoskeletal	Pulmonary	Gastrointestinal	Genitourinary
#1	At onset	Delayed walking*	Easy fatigability	Sleep apnea	Aspiration during feeding	None
	Current	Walks unassisted; wide-based gait with frequent tripping and falls; uses motorized scooter for long distances	Ptosis; weakness of neck flexors, shoulder abductors, hip abductors; paraspinal muscles & ankle dorsiflexors; spinal extension with lumbar lordosis, scoliosis, scapular winging, wide based, foot-slapping gait	Unassisted ventilation	None	None
#2	At onset	Delayed sitting, pull-to-stand, and walking	Lethargy, hypotonia	Apneic episodes	Feeding difficulty, vomiting, diarrhea	None
	Current	Walks unassisted; wide-based gait	Myopathic facies; scapular winging; weakness of neck flexors, hip abductors, ankle dorsiflexors; genu recurvatum, and medial pronation at ankle, elbow hyperextension; stepto gait pattern on stairs	Unassisted ventilation; New onset snoring and sleep disturbances/apnea; suspected aspiration pneumonia	Choking on saliva, persistent gastroesophageal reflux,	Urinary retention and overflow incontinence, chronic constipation
#3	At onset	Poor head control till age 6 months	Needing assistance to pull to stand from a prone position, wide-based gait with lumbar lordosis,	Weak cry	None	None
	Current	Walks unassisted; wide-based gait with frequent tripping and falls	Ptosis; lingual muscle weakness, lumbar lordosis, scapular winging; weakness of neck flexors and abdominals; core muscle weakness, decreased hip extensor and hip abductor strength; scoliosis	Unassisted ventilation	Cramping, vomiting, diarrhea	None
#4	At onset	Delayed walking	Unsteady gait with frequent falls	Apnea and bradycardia as newborn	None	None
	Current	Walks unassisted; unsteady and abnormal gait with frequent falls; scoots in sitting for mobility	Delayed motor skills; poor pincer grasp; lumbar lordosis, scapular winging; weakness of abdominals, hip extensors, abductors and adductors, ankle plantar flexors, and neck flexors	Unassisted ventilation; Snoring, apneic pauses

^*Lost to follow-up at this age.