Neurodegeneration With Brain Iron Accumulation

Neurodegeneration with brain iron accumulation (NBIA) is a group of inherited neurologic disorders in which iron accumulates in the basal ganglia. Symptoms include progressive dystonia (a movement disorder resulting in muscular spasms, twisting, and repetitive movements) spasticity, parkinsonism (slurred or slow speech, stiffness of the muscles, slow movement, and visible tremors), inability to coordinate movements (ataxia), neuropsychiatric abnormalities (confusion, disorientation, seizures, stupor, dementia), and eye problems, such as optic atrophy or retinal degeneration. The age of onset ranges from infancy to late adulthood, and the rate of progression varies. Some subtypes have cognitive decline. Cerebellar atrophy is common in many cases.

There are ten recognized types of NBIA, classified according to the altered gene that causes the disease. These genes include PANK2, PLA2G6, C19orf12, FA2H, ATP13A2, WDR45, COASY, FTL, CP and  DCAF17. Eight of the ten types of NBIA are inherited in an autosomal recessive manner. The type known as beta-propeller protein-associated neurodegeneration (BPAN), caused by mutations in the WDR45 gene, is inherited in an X-linked dominant manner. The neuroferritinopathy, caused by mutations in the FTL gene, is inherited in an autosomal dominant manner.

There is no cure for NBIA. Treatment is symptomatic, and includes medication such as baclofen, trihexyphenidyl, botulinum toxin, and a procedure known as  deep brain stimulation to treat dystonia.  Levodopa and anticholinergic drugs may also bring some relief of parkinsonian symptoms.

The NBIA Disorders Association has detailed information about NBIA.