Holmes tremor in progressive multifocal leukoencephalopathy: A video case report

Background

Progressive multifocal leukoencephalopathy (PML) is a rare demyelinating disease of the central nervous system caused by the John Cunningham virus. Various brain regions are affected by PML. Therefore, patients with PML show various neurological symptoms. However, tremors are rare neurological symptoms of PML.

Case Presentation

A 49-year-old man developed intermittent slow tremor in the left hand, bilateral dysesthesia and gait disturbance. Brain magnetic resonance imaging showed hyperintense lesions in the right parietofrontal lobe, right thalamus, left middle cerebellar peduncle, left dentate nucleus, pons and medulla oblongata on fluid-attenuated inversion recovery images. The patient was positive for HIV antibodies. In addition, HIV-1 RNA was increased. Quantitative real-time polymerase chain reaction identified John Cunningham virus DNA in the cerebrospinal fluid; HIV-associated PML was diagnosed. Surface electromyography showed 3-Hz grouped discharges in the left flexor carpi ulnaris and extensor carpi radialis, which were consistent with Holmes tremor (HT). Although we administered antiretroviral therapy and mirtazapine, the neurological and radiological findings progressively worsened, and the patient died on day 90. Including the present case, there have been 10 reported cases of PML with HT.

Conclusions

Although tremors are rarely observed in PML, HT might be a common tremor phenotype in patients with PML. If the neurologist observes HT in patients with multiple brain lesions, PML should be considered.