Sixth cranial nerve palsy: a rare clinical symptomof Herpes simplex virus-1 and 2 encephalitis
Medical Review (Med. pregled), 2023, 59(6), 55-60.
S. Zhelyazkova1,2, S. Cherninkova1,2, I. Tarnev1,2,3
1 Clinic of Nervous System Diseases, University Hospital “Alexandrovska”
2 Department of Neurology, Medical University – Sofia
3 Department of Cognitive Science and Psychology, New Bulgarian University, Sofia
Abstract. Herpes simplex encephalitis (HSE) is one of the most common causes of spo¬radic encephalitis of adults with the majority of cases due to Herpes simplex virus typе 1 (HSV-1). The clinical presentation of HSV-1 encephalitis usually includes a rapid onset of fever, headache, seizures with focal neurologic signs, and impaired consciousness. The clinical symptoms of HSV-2 encephalitis may include altered level of consciousness, hemiparesis, and hemisensory loss. Abducens cranial nerve involvement by herpes simplex virus 1 and 2 is a rare entity even in patients with human immunodeficiency virus infection. We describe two cases of Herpes simplex virus-1 and 2, encephalitis, who presented with lesion of the abducens nerve (six cranial nerve) as the main clinical symptom of the disease. Brain MRI of both patients showed a hyperintense lesson in the brainstem on T2-weighted images. Cerebrospinal fluid polymerase chain reaction (PCR) amplification analysis was positive for HSV-2 (the first patient) and HSV-1 (the second patient). Acyclovir therapy was started and the symptoms gradually disappeared.
Key words: Herpes simplex virus-1 and 2, abducens nerve lesion, encephalitis, clinical cases
Address for correspondence: Sashka Zhelyazkova, MD, e-mail: doc_sashka@abv.bg