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Inherited neuropathies are a diverse group of diseases, ranging from those where neuropathy is the primary feature to those occurring within multisystem disorders. Sensory-ataxic-neuropathy (SAN) presents with loss of proprioception and vibration sense, with relatively preserved muscle strength. Deletions in ITRP1 have been associated with a variable phenotype including ataxia, dysarthria, nystagmus, and rarely peripheral neuropathy. A 57-year-old woman presented with a chronic asymmetrical neuropathy, accompanied by numbness, and shooting pains who was treated with cyclophosphamide and prednisolone at local hospital for a possible vasculitis. Neurophysiology revealed a patchy axonal, sensory polyneuropathy mainly affecting the upper limbs. Investigations revealed positive ENA antibodies, rheumatoid factors as well as a foci of lymphocytes on lip biopsy. Cerebrospinal fluid (CSF) was normal, and dorsal ulnar and sural nerve biopsies did not show evidence of inflammation. A trial of IVIG was administered for a possible Sjogren neuropathy without objective clinical improvement. She experienced slow disease progression over 10 years and developed mild head titubation. Whole-genome-sequencing identified a heterozygous ~6.5Mbp terminal copy-number-loss on chromosome 3 involving the ITPR1 gene. We report an ITPR1 deletion in a patient with a SAN, highlighting its genetic and phenotypical heterogeneity and identifying ITPR1 as a cause of isolated SAN.saif.haddad@ucl.ac.uk