From the Guidelines
Red flags in a patient presenting with headache require immediate medical attention as they may indicate serious underlying conditions, and the most critical red flags include sudden onset of severe headache (thunderclap headache), headache accompanied by fever, neck stiffness, or rash, and headache with neurological deficits such as weakness, numbness, visual changes, speech difficulties, or altered mental status, as indicated by the most recent and highest quality study 1. These warning signs may indicate serious conditions such as subarachnoid hemorrhage, meningitis, brain tumor, temporal arteritis, or cerebral venous thrombosis. Some key red flags to evaluate in a patient presenting with a headache include:
- Sudden onset of severe headache (thunderclap headache)
- Headache accompanied by fever, neck stiffness, or rash
- Headache with neurological deficits such as weakness, numbness, visual changes, speech difficulties, or altered mental status
- Headaches that wake the patient from sleep, progressively worsen over days or weeks, or change in character from previous headache patterns
- Headache in patients with cancer, HIV, or immunosuppression
- Headache following head trauma
- Headache associated with systemic symptoms like weight loss or hypertension When these warning signs are present, immediate neuroimaging (CT or MRI), lumbar puncture, or other diagnostic tests may be necessary to rule out life-threatening causes, as suggested by 1 and 1. It is essential to note that the presence of these red flags may indicate a need for urgent evaluation and treatment to prevent morbidity and mortality, and the evaluation should be guided by the most recent and highest quality evidence, such as the study published in 1. In addition to these red flags, other concerning features include headache with atypical aura, head trauma, unexplained fever, impaired memory, and focal neurological symptoms, as mentioned in 1. The diagnosis and management of headache disorders, including the identification of red flags, are crucial in preventing morbidity and mortality, and the most recent and highest quality study 1 provides the best guidance on this topic.
From the Research
Headache Red Flags
The following are red flags to evaluate in a patient presenting with a headache:
- Sudden onset of headache 2, 3, 4
- Onset of headache after 50 years of age 2, 5, 4
- Increased frequency or severity of headache 2
- New onset of headache with an underlying medical condition 2
- Headache with concomitant systemic illness 2
- Focal neurologic signs or symptoms 2, 3, 4
- Papilledema 2, 4
- Headache subsequent to head trauma 2
- Acute thunderclap headache 4
- Fever 4
- Meningeal irritation on physical examination 4
- Impaired consciousness 4
- Concern for acute glaucoma 4
Evaluation and Management
A thorough neurologic examination should be performed, with abnormal findings warranting neuroimaging to rule out intracranial pathology 2, 3, 4. The preferred imaging modality to rule out hemorrhage is noncontrast computed tomographic (CT) scanning followed by lumbar puncture if the CT scan is normal 2, 4. Magnetic resonance imaging (MRI) is more expensive than CT scanning and less widely available; however, MRI reveals more detail and is necessary for imaging the posterior fossa 2. Cerebrospinal fluid (CSF) analysis can help to confirm or rule out hemorrhage, infection, tumor and disorders related to CSF hypertension or hypotension 2. Referral is appropriate for patients with headaches that are difficult to diagnose, or that worsen or fail to respond to management 2.