A 53-year-old woman was admitted to an American clinic with complaints of fever and abdominal pain. A month before, she had undergone a kidney transplant, after which she regularly took the immunosuppressants cyclosporine and tacrolimus. Soon, the patient began to develop right-sided hemiparesis and progressive encephalopathy, due to which she could not speak, but periodically followed the doctor's commands. An MRI revealed mesencephalic foci of hyperintensity in the thalamus, tegmentum, and substantia nigra of the brain, forming a picture known as the panda sign (the sign of the giant panda of the midbrain). Dr. Carlton Watson and colleagues from Vassar Brothers and Westchester Medical Centers shared the case in Neurology.
The panda symptom is most often observed in Wilson's disease, less often in Leigh syndrome, acute disseminated encephalomyelitis, rabies and toxic leukoencephalopathy. However, the etiology of the woman turned out to be different - PCR of the cerebrospinal fluid revealed the West Nile fever virus. She was prescribed five doses of specific immunoglobulin against the virus and a month-long course of the antiviral drug remdesivir, after which she was sent for rehabilitation. There, her speech was restored, but hemiparesis remained. Thus, although the panda symptom is not specific for West Nile fever, when it is detected, this infection should be taken into account, especially in patients with immunosuppression.