Infantile neuroaxonal dystrophy (INAD) is a neurodegenerative disorder associated with a mutation in the PLA2G6 gene. It is the second most common type of neurodegeneration with brain iron accumulation (NBIA) mainly in the globus pallidus, caudate nucleus and substantia nigra after pantothenate kinase-associated neurodegeneration (PKAN, formerly Hallervorden-Spatz disease).
INAD is inherited in an autosomal recessive fashion. PLA2G6 encodes a calcium-independent phospholipase and has been associated with infantile neuroaxonal dystrophy (INAD), atypical neuroaxonal dystrophy (NAD) and dystonia-parkinsonism. PLA2G6 is protective of mitochondrial health. It is also important for membrane homoeostasis and calcium signalling. INAD is characterised histologically by axonal spheroid bodies. Phenotypically, INAD is characterised by psychomotor regression with early onset between six months and three years of age. Hypotonia occurs early with severe weakness that may be replaced by spasticity. Many INAD patients also experience progressive dementia. Death usually occurs before the age of 10 years due to respiratory complications. Patients may present for gastrostomy tube and tracheostomy placement due to bulbar dysfunction and some may require surgical correction of scoliosis to improve respiratory status. The main anaesthetic concern for INAD patients is their poor preoperative respiratory status due to poor airway clearance and respiratory mechanics that often make postoperative intubation necessary.