Patients presenting with headaches need to be screened for primary vs secondary etiologies. “Red flags” associated with secondary headaches are crucial to identify. Physical examination should be completed with careful assessment of clues obtained during the history. It should include blood pressure measurements, assessment of mental status, and cranial nerve (CN) examination including but not limited to fundoscopic examination, gait, and facial strength.
An overview of the mnemonic SNNOOP10 that considers the “red flag” features that may suggest an underlying secondary etiology for acute or subacute headaches.
Red Flags in Headache
Clinical characteristic
- S Systemic symptoms, including a fever: Non-vascular intracranial events from an inflammatory or infectious process
- N Neoplasm history: Brain neoplasm or metastasis
- N Neurologic focal deficits (e.g., diminished level of consciousness): Vascular intracranial or cervical events; brain abscess; meningitis; opportunistic infections
- O Onset is sudden: Subarachnoid hemorrhage and other secondary headaches with vascular etiology
- O Older age (50+ years): Giant cell arteritis or other vascular intracranial process; neoplasms and other non-vascular intracranial disorder
- P Pattern of headache changes: Neoplasm, headaches attributed to intracranial or cervical vascular and non-vascular etiologies
- P Positional headache in nature: Intracranial hypertension or hypotension
- P Precipitating factors include sneezing, coughing, or exercise: Posterior fossa malformations; Chiari malformation
- P Pregnancy or puerperium: Acute intracranial or cervical vascular etiologies
- P Painful eye with autonomic features: Pathology in posterior fossa, cavernous sinus, or pituitary gland; ophthalmic etiologies
- P Post-traumatic onset of headache: Headaches related to intracranial or cervical vascular etiologies; post-dural puncture headaches; headaches related to pre-eclampsia; venous sinus thrombosis; anemia; hyperthyroidism; hypothyroidism; diabetes
- P Pathology of the immune system (e.g., HIV, T-cell lymphoma): Headaches related to intracranial non-vascular events; brain abscess; opportunistic infections
- P Painkiller (analgesic) overuse headache, or new drug at onset of headache: Headaches related to non-vascular intracranial etiology related to adverse drug metabolite interaction
References:
- Hernandez J, Molina E, Rodriguez A, Woodford S, Nguyen A, Parker G, Lucke-Wold B. Headache Disorders: Differentiating Primary and Secondary Etiologies. J Integr Neurosci. 2024 Feb 20;23(2):43. [Medline]
- Raam R, Tabatabai RR. Headache in the Emergency Department: Avoiding Misdiagnosis of Dangerous Secondary Causes, An Update. Emerg Med Clin North Am. 2021 Feb;39(1):67-85. [Medline]
Created Nov 28, 2024.
