Neopterin plasma concentrations in patients with aneurysmal subarachnoid hemorrhage: correlation with infection and long-term outcome

J Neurosurg. 2016 May;124(5):1287-99. doi: 10.3171/2015.3.JNS142212. Epub 2015 Sep 25.

Abstract

OBJECT Aneurysmal subarachnoid hemorrhage (aSAH) is associated with high rates of mortality and morbidity. The main predictor for the poor outcome is the World Federation of Neurosurgical Societies (WFNS) scale. However, this scale does not take into account proinflammatory events, such as infection occurring after the aSAH, which could modify the long-term status of patients. The aim of this study was to evaluate neopterin as an inflammatory biomarker for outcome and infection prediction in aSAH patients. METHODS Plasma concentrations of neopterin were measured in 61 aSAH patients (22 male and 39 female; mean age [± SD] 52.8 ± 11.8 years) using a commercial ELISA kit. Samples were collected daily for 10 days. Outcome at 12 months was determined using the Glasgow Outcome Scale (GOS) and dichotomized as poor (GOS score 1, 2, or 3) or good (GOS score 4 or 5). Infection was determined by the presence of a positive bacterial culture. RESULTS Patients with poor outcome at 12 months had higher concentrations of neopterin than patients with good outcome. In the same way, patients who had an infection during the hospitalization had significantly higher concentrations of neopterin than patients without infection (p = 0.001). Moreover, neopterin concentrations were significantly (p < 0.008) elevated in infected patients 2 days before infection detection and antibiotic therapy. CONCLUSIONS Neopterin is an efficient outcome predictor after aSAH. Furthermore, it is able to differentiate between infected and uninfected patients as early as 2 days before clinical signs of infection, facilitating earlier antibiotic therapy and better management.

Keywords: AUC = area under the ROC curve; DCI = delayed cerebral ischemia; EVD = external ventricular drain; GCS = Glasgow Coma Scale; GOS = Glasgow Outcome Scale; NSE = neuron-specific enolase; ROC = receiver operating characteristic; ROS = reactive oxygen species; S100β = S100 calcium binding protein-β; WBC = white blood cell; WFNS = World Federation of Neurosurgical Societies; aSAH = aneurysmal subarachnoid hemorrhage; aneurysmal subarachnoid hemorrhage; biomarker; infection; inflammation; neopterin; outcome; vascular disorders.

MeSH terms

  • Adult
  • Aged
  • Bacterial Infections / blood*
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Follow-Up Studies
  • Glasgow Outcome Scale
  • Humans
  • Inflammation Mediators / blood*
  • Male
  • Middle Aged
  • Neopterin / blood*
  • Outcome Assessment, Health Care
  • S100 Calcium Binding Protein beta Subunit / blood
  • Statistics as Topic
  • Subarachnoid Hemorrhage / blood*

Substances

  • Inflammation Mediators
  • S100 Calcium Binding Protein beta Subunit
  • S100B protein, human
  • Neopterin