Table 1.

Spectrum of PLP1-Related Disorders

PhenotypeAge of OnsetNeurologic FindingsAmbulationSpeechAge at Death
Severe ‘connatal’ PMDNeonatal periodNystagmus at birth; pharyngeal weakness; stridor; hypotonia; severe spasticity; ± seizures; cognitive impairmentNever achievedAbsent, but nonverbal communication & speech comprehension possibleInfancy to 3rd decade
Classic PMDFirst 5 yearsNystagmus in 1st 2 mos; initial hypotonia; spastic quadriparesis; ataxia titubation; ± dystonia, athetosis; cognitive impairmentW/assistance if achieved; lost in childhood / adolescenceUsually present3rd-7th decade
PLP1 null syndromeFirst 5 yearsNo nystagmus; mild spastic quadriparesis; ataxia; peripheral neuropathy; mild-to-mod cognitive impairmentPresentPresent; usually worsens after adolescence5th-7th decade
Complicated spastic paraplegia (SPG2)First 5 yearsNystagmus; ataxia; autonomic dysfunction 1; spastic gait; little or no cognitive impairmentPresentPresent4th-7th decade
Uncomplicated spastic paraplegia (SPG2)Usually first 5 years; may be 3rd-4th decadeAutonomic dysfunction 1; spastic gait; normal cognitionPresentPresentNormal

Spastic urinary bladder

From: PLP1-Related Disorders

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