Neurological manifestations of xeroderma pigmentosum in two siblings

Two sibs with xeroderma pigmentosum and neurological complications are described. These included progressive dementia, chorea, perceptive deafness, cortico-spinal tract degeneration, peripheral neuropathy and skeletal abnormalities. Electromyographic studies showed evidence of chronic denervation and the motor and sensory nerve conduction studies indicated the presence of a mixed axonal peripheral neuropathy in both cases. A sural nerve biopsy in 1 case demonstrated a global fall out of both myelinated and unmyelinated nerve fibres and a muscle biopsy in this patient confirmed the presence of chronic denervation atrophy with widespread reinnervation. The significance of these findings is discussed and the basic defect in xeroderma pigmentosum is reviewed.