Herpes simplex encephalitis as a complication of neurosurgical procedures: report of 3 cases and review of the literature

Abstract

Background: Herpes simplex virus (HSV) is the most common identified cause of focal encephalitis worldwide. However, postoperative HSV encephalitis (HSVE) is a rare complication of neurosurgical procedures and a significant clinical challenge

Method: We describe 3 cases of postoperative HSVE and review all published reports. A total of 23 cases were identified.

Discussion: Clinical heterogeneity represents a diagnostic challenge in the postoperative setting. Cerebral magnetic resonance imaging showed typical findings in a minority of patients only, whereas HSV-specific polymerase chain reaction on the cerebrospinal fluid proved to be a valuable test. The postoperative viral pathophysiology remains a subject of debate. The rate of adverse outcome is high and early antiviral treatment seems to be a strong predictor of clinical outcome.

Conclusion: We recommend early empirical treatment for any patient presenting with post-neurosurgical lymphocytic meningo-encephalitis, and prophylactic antiviral treatment for patients with a history of previous HSVE who will undergo a neurosurgical procedure.

Keywords: Complication; Encephalitis; Herpes simplex virus; Meningitis; Neurosurgery; Postoperative.

Fig. 1

Coronal FLAIR MRI sequence illustrates a diffuse leptomeningeal enhancement (arrows) after surgery of an epidermoid cyst of the right cerebellopontine angle

Fig. 2

Post-surgical CT visualization of a right frontal heterogeneous collection (2a, left). MRI showed no empyema but ischemic lesions of the right deep frontal white matter (2b, right)

Fig. 3

Sequels of HSVE at the level of the temporal lobe and right hippocampus (3a, upper left, arrows and asterisk). Post-surgical MRI shows areas of suspected encephalitis with high signal on T2 in the right frontal, parietal and temporal lobes at 3 weeks (3b, upper right), associated with hemorrhagic transformation and mass effect one month later (3c, lower left). Follow-up MRI at 45 days showed large sequelae of the temporal lobe (3d, lower right)