Clinical characteristics
This disorder resembles many lysosomal storage disorders.
It can present at birth with hypotonia, feeding difficulties, and respiratory distress.
There is always a developmental delay, ranging from moderate to profound.
Seizure may develop shortly after birth or later in childhood.
Facial features can be normal, or may become progressively coarse, including striking tongue overgrowth.
Patients have non-specific white matter changes on brain MRI that resemble a leukodystrophy.
The most severe patients become unable to interact, have uncontrollable seizures, and become depending on mechanical ventilation.