Related Experiment Video
Updated: Sep 3, 2025
Pre-Chiasmatic, Single Injection of Autologous Blood to Induce Experimental Subarachnoid Hemorrhage in a Rat Model
Published on: June 18, 2021
Adding eosinophil count to EMERALD rules predicts subarachnoid haemorrhage better in emergency department
Adem Kaya1, Salim Satar2, Muge Gulen1
1Department of Emergency Medicine, Adana City Training and Research Hospital, Mithat Ozhan Avenue, 01370, Yuregir, Adana, Turkey.
Background:
Subarachnoid haemorrhage (SAH) clinical decision rules can provide successful results in the differential diagnosis of non-traumatic headache.
Aim:
The aim of this study is to investigate whether a laboratory parameter that can be added to clinical decision-making rules can better predict subarachnoid haemorrhages in patients presenting to the emergency department with headache.
Methods:
We conducted a retrospective cohort study between March 2017 and March 2019. Patients over the age of 18 who admitted to the emergency department with non-traumatic, acute headache last 14 days before admission and evaluated by imaging and laboratory studies were included in the study.
Results:
A total of 867 patients were included and 141 of them had SAH. In detecting the SAH, Ottawa SAH rule sensitivity (85.1%), specificity (47.1%), positive predictive value (PPV) (23.8%) and negative predictive value (NPV) (94.2%), and for EMERALD SAH, rule sensitivity (96.4%), specificity (43.2%), PPV (24.8%) and NPV (98.4%). In the regression analysis, statistically significant result was obtained to exclude the diagnosis of SAH with the decrease in the eosinophil value (cutoff < 0.085 10^3/µL, OR: 0.011, 95% CI: 0.001-0.213, p = 0.003). When eosinophil value was added to EMERALD SAH rule, it provided a 100% of sensitivity, a 38.4% of specificity, a 24% of PPV and a 100% of NPV in detecting the SAH.
Conclusions:
EMERALD SAH rule plus eosinophil, which offers 100% sensitivity and NPV for predicting SAH in adult non-traumatic headaches, may be recommended as a successful and practical decision rule for clinical use according to the Ottawa and EMERALD SAH rule.
