Unexplained worsening of parkinsonian symptoms in a patient with advanced Parkinson's disease as the sole initial presentation of COVID-19 infection: a case report.

To our knowledge, worsening of PD symptoms as the sole initial manifestation of SARS-CoV-2 infection, in the absence of other cardinal features of COVID-19, has not been reported in the literature. We suggest testing for COVID-19 infection in patients with PD, especially advanced cases, who present with unexplained worsening of symptoms, even in the absence of COVID-19 cardinal features.