Brachial amyotrophic diplegia (segmental proximal spinal muscular atrophy) associated with HIV infection.

Several forms of motor neuron disease occurring in association with HIV infection have been described. Segmental proximal spinal muscular atrophy or brachial amyotrophic diplegia, a rare segmental variant of motor neuron disease with isolated bilateral upper extremity weakness, has previously been described in a single case report. We describe a patient who is HIV-seropositive presenting with this phenotype and illustrate novel findings on MRI of the cervical cord, consisting of focal atrophy and T2 hyperintense signal change involving the anterior grey matter. Additionally, a number of differences compared with patients without HIV presenting with this motor neuron disease variant are highlighted.