Predictive Factors and Clinical Prediction Score for Serious Intracranial Causes in Acute Nontraumatic Headache at an Emergency Department

Table 2

Comparison of red flag signs and investigations.

	Nonserious intracranial headache (366 patients)	Serious intracranial headache (88 patients)	value
Red flag signs
Age >50 years	231 (63.1)	48 (54.5)	0.174
Abrupt onset	58 (15.8)	33 (37.5)	<0.001
Positional provocation	5 (1.4)	4 (4.5)	0.076
Systemic symptoms	26 (7.1)	22 (25)	<0.001
Secondary risk factors	26 (7.1)	21 (23.9)	<0.001
Neurological deficit	13 (3.6)	29 (33)	<0.001
Investigations
Performed CT brain	70 (19.1)	88 (100)	<0.001
CT brain results
Subarachnoid hemorrhage	0 (0)	12 (13.6)	<0.001
Intracerebral hemorrhage	0 (0)	15 (17.0)	<0.001
Infarction	0 (0)	6 (6.8)	<0.001
Tumor with/without complications	0 (0)	21 (23.9)	<0.001
Venous sinus thrombosis	0 (0)	4 (4.5)	0.001
Hydrocephalus	0 (0)	1 (1.1)	0.194
Brain abscess	0 (0)	1 (1.1)	0.194
Within normal limits	70 (19.1)	28 (31.8)	0.014
Performed CTA	0 (0)	16 (18.2)	<0.001
CTA results
AVM	0 (0)	6 (6.8)	<0.001
Aneurysm	0 (0)	7 (8)	<0.001
Within normal limits	0 (0)	3 (3.4)	0.007
Performed MRI	0 (0)	23 (26.1)	<0.001
MRI results
Leptomeningeal enhancement	0 (0)	1 (1.1)	0.194
Focal meningoencephalitis	0 (0)	1 (1.1)	0.194
Brain tumor/metastasis	0 (0)	17 (19.3)	<0.001
Cerebral infarction	0 (0)	2 (2.3)	0.037
Venous sinus thrombosis	0 (0)	1 (1.1)	0.194
AVM	0 (0)	1 (1.1)	0.194
Performed lumbar puncture	5 (1.4)	26 (29.5)	<0.001
CSF findings
Bacterial meningitis	0 (0)	2 (2.3)	0.037
Viral meningitis	0 (0)	12 (13.6)	<0.001
Fungal meningitis	0 (0)	6 (6.8)	<0.001
Eosinophilic meningitis	0 (0)	1 (1.1)	0.194
Blood	0 (0)	1 (1.1)	0.194
Normal profile	5 (1.4)	4 (4.5)	0.076
Pathogens
Beta Streptococcus group B	0	1
Pseudomonas aeruginosa	0	1
Cryptococcus neoformans	0	5
Human herpes virus	0	2

Data are presented as n (%) unless indicated otherwise. values <0.05 are statistically significant. CT = computed tomography; CTA = computed tomographic angiography; AVM = arteriovenous malformation; MRI = magnetic resonance imaging.