Oral bacterial genic expression detection in aneurysm wall of a French population sample - preliminary monocentric study.

INTRODUCTION: The etiology of brain aneurysms remains poorly understood. Finnish research suggests that oral bacteria might contribute to the development and rupture of brain aneurysms. Previous studies by our team have not confirmed these findings, likely due to methodological differences. We aimed to replicate the Finnish study with a French population, using the same primers and comparing the results to internal controls. METHODS: We used RT-qPCR to retrospectively analyze the expression of oral bacterial genes in eight patients. During surgical procedures, four tissue types were consistently sampled from each patient: the aneurysmal wall, the superficial temporal artery (STA), the middle meningeal artery (MMA), and the dura mater (DM). Results were expressed as fold differences employing the 2-∆∆Ct method, and statistical analyses were performed accordingly. RESULTS: Our cohort included eight patients, evenly split into ruptured and unruptured groups. The sex distribution was balanced (4 females, 4 males). We observed DNA expression from oral bacteria in all sampled tissues; however, there were no significant differences between the ruptured and unruptured groups. CONCLUSION: We detected oral bacterial gene expression in the aneurysmal wall, STA, MMA, and DM in a sample of French patients. Although limited by the small sample size, our results suggest a potential role for bacterial involvement in vascular invasiveness related to bacteremia. These findings do not definitively link oral bacteria to the pathogenesis of aneurysm development and rupture.

Delayed cranial neuropathy after neurosurgery caused by herpes simplex virus reactivation: report of three cases.

BACKGROUND: Delayed cranial neuropathy is an uncommon complication of neurosurgical interventions of which the exact etiology is uncertain. Several authors have hypothesized that reactivation of herpesviruses may play a role. CASE DESCRIPTIONS: The first patient underwent microvascular decompression of the left facial nerve because of hemifacial spasm. Nine days postoperatively, he developed severe facial weakness on the ipsilateral side. The polymerase chain reaction for herpes simplex virus (HSV) was positive in the cerebrospinal fluid (CSF). Treatment with intravenous acyclovir was initiated, after which a rapid and marked improvement was observed. The second patient developed left-sided facial numbness 20 days after microvascular decompression of the left facial nerve. The polymerase chain reaction for HSV was positive in the CSF. Treatment with intravenous acyclovir resulted in full recovery. The third patient underwent a suboccipital craniectomy with excision of a meningioma located at the left petrosal apex. Three months postoperatively, she developed multiple cranial neuropathies (involving cranial nerves V, VI, VIII, and XII). This was accompanied by serologic evidence of HSV reactivation and a positive polymerase chain reaction for HSV in the CSF. The patient was successfully treated with intravenous acyclovir. CONCLUSIONS: The 3 reported cases provide evidence that delayed postoperative cranial neuropathy can be caused by HSV reactivation and can involve multiple cranial nerves. An increased awareness of this treatable postoperative complication is warranted.