SPPRS is a complex syndrome that can present with various symptoms. The following symptoms are shared by all reported cases:
• Delayed development and moderate to severe intellectual disability. Infants born with SPPRS may not reach normal milestones such as learning to speak, walk, or use the toilet.
• Leg muscle issues known as hypotonia, dystonia, and spastic paraplegia. This means that the legs may be very weak, with stiff muscles that contract involuntarily (spasms). Many reported SPPRS patients have an unsteady or ‘waddling’ walk or are non-ambulatory, meaning they are bedridden or require a wheelchair to move.
• Ataxia, meaning difficulty with balance and coordination of movement.
These additional symptoms have been described in some, but not all SPPRS patients:
• Seizures, specifically myoclonic seizures where muscles briefly and suddenly jerk.
• Changes in growth and appearance, including short stature, being overweight, and a deformed spine and feet. Infants may also be born with an unusually large head.
• Microcephaly and cerebral atrophy, which means the head is smaller than expected and the brain does not grow or develop normally.
• Problems with the senses, including myopia (being near-sighted), strabismus (being cross-eyed), and hearing loss.
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