Excessively Elevated C-Reactive Protein and Seizure Outcome in 87 Patients Undergoing Surgery for Temporal Lobe Epilepsy

Aims: We present a series of 87 patients who underwent surgery for therapy refractory temporal lobe epilepsy. This study focuses on seizure outcome and on the report of an interesting phenomenon: excessively elevated C-reactive protein (CRP) levels in the absence of clinical infection following epilepsy surgery.

Patients and Methods: We followed 87 patients (m = 39, f = 48; mean age 33.73±12.92, range 5 to 67 years) who underwent surgery between July 2003 and November 2011. In 73 cases, a selective amygdalohippocampectomy was performed and an anterior 2/3 resection of the temporal lobe was performed in 14 cases. CRP serum levels were measured and seizure outcome was classified according to the ILAE classification by Wieser et al (mean follow-up: 38.72 months).

Results: In 70 cases (80.5%) patients were postoperatively completely seizure-free and no auras were observed (ILAE class 1), 3 patients (3.4%) had only auras, but no seizures (ILAE class 2), in 8 cases (9.2%) one to three seizure days per year were noted (ILAE class 3). Only three patients (3.4%) belonged to the ILAE class 4 (four seizures per year to 50% reduction of baseline seizures) and another three patients (3.4%) had less than a 50% reduction of baseline seizure days (ILAE class 5). At last follow-up, 17 patients (19.5%) were completely off antiepileptic medications, in 24 cases (27.6%) the antiepileptic regimen was reduced, 42 patients (48.3%) stayed on the same medications, and 4 patients (4.6%) needed additional medications. Perioperative complications included one case (1.1%) of a left-sided hemiparesis, one case (1.1%) of oculomotor nerve palsy, three cases (3.4%) of wound infections, and one case (1.1%) of a deep vein thrombosis. In 59 patients of this group, a complete dataset of postoperative CRP values was available. Mean CRP peak value was 100.86 mg/L (SD 56.00, range 16 to 258). Two patients (3.4%) had a CRP peak above 200 mg/L, 12 patients (20.3%) had a peak higher than 150 mg/L.

Conclusions: Seizure outcome was excellent with a clinical benefit in 96.6% of the patients and with 80.5% being completely seizure-free. Although postoperative elevation of CRP is a known phenomenon, the rise of CRP in this patient group is much higher than in patients undergoing other neurosurgical procedures at our institution. Reasons for this phenomenon might include the manipulation of circumventricular organs, which are involved in the inflammatory cascade following tissue damage.