In a previously healthy 12‑year‑old girl presenting with acute headache, nausea, vomiting and vertigo without trauma, fever, or focal neurological deficits, what are the appropriate differential diagnoses and initial management plan?

Differential Diagnosis and Management for 12-Year-Old with Headache, Nausea, Vomiting, and Vertigo

Most Likely Diagnosis: CNS Infection (Meningitis/Encephalitis)

In a previously healthy 12-year-old presenting with headache, nausea, vomiting, and vertigo, CNS infection (viral or bacterial meningitis/encephalitis) must be ruled out first, as this represents the most life-threatening condition requiring immediate intervention. 1

Why CNS Infection is Priority #1:

• The classic triad of headache, vomiting, and fever strongly suggests CNS infection 1
• Vertigo can result from dural irritation and localized encephalitis affecting vestibular pathways 2, 1
• Altered neurological function (including vertigo and visual disturbances) with headache and vomiting is the hallmark presentation of encephalitis 1
• Empiric antimicrobial therapy must NOT be delayed while awaiting diagnostic confirmation, as delays worsen outcomes and increase mortality 1

Complete Differential Diagnosis (Ranked by Urgency)

Tier 1: Life-Threatening Conditions Requiring Immediate Action

1. Bacterial Meningitis/Encephalitis 1

   • Presents with fever, headache, vomiting, altered mental status
   • Vertigo from dural irritation and cranial nerve involvement
   • Requires immediate antibiotics before imaging if unstable

2. Brain Abscess/Subdural Empyema 1

   • Can present with fever, headache, vomiting, and vertigo
   • Often follows sinusitis or otitis media in older children
   • Requires urgent surgical evaluation

3. Cerebellar Stroke 2, 3

   • Rare (1-3% of acute ataxia cases) but critical to diagnose 2
   • Presents with acute vertigo, nausea, vomiting, ataxia
   • Wallenberg syndrome can present with rotary vertigo after minor trauma 3

4. Intracranial Hemorrhage/Subarachnoid Hemorrhage 2, 4

   • "Thunderclap" or "worst headache of life" presentation 4
   • Vomiting and altered consciousness common
   • CT has 98% sensitivity for acute SAH 1

5. Acute Hydrocephalus 5

   • Headache with vomiting and vertigo from increased ICP
   • Accounts for 0.9% of ED headache presentations 5

Tier 2: Serious Conditions Requiring Urgent Evaluation

1. Cerebral Venous Thrombosis 6

   • Can present with headache, vomiting, and vertigo
   • May have normal initial MRI—requires dedicated venography 6
   • Can mimic idiopathic intracranial hypertension 6

2. Posterior Fossa Tumor 5, 7

   • Accounts for 0.7-2.6% of ED headache presentations 5, 7
   • Occipital headache with vomiting and vertigo
   • Progressive symptoms over weeks to months

3. Acute Disseminated Encephalomyelitis (ADEM) 1

   • Follows viral infection or vaccination
   • Presents with encephalopathy, fever, vertigo
   • MRI shows large confluent T2 lesions 1

Tier 3: Common Benign Conditions

1. Vestibular Migraine 2

   • Vertigo attacks lasting minutes to hours 2
   • Often positive family history of migraine
   • Photophobia more common than visual aura 2
   • However, fever is NOT typical and should raise suspicion for secondary causes 1

2. Post-Viral Vestibular Neuritis 2

   • Acute prolonged vertigo (12-36 hours) with nausea/vomiting 2
   • No hearing loss, tinnitus, or aural fullness 2
   • Follows viral illness

3. Benign Paroxysmal Positional Vertigo (BPPV) 2

   • Positional vertigo lasting seconds, not minutes 2
   • Not associated with headache or vomiting 2
   • Less likely in this age group

4. Upper Respiratory Infection 7

   • Most common cause of acute headache in ED (57% of cases) 7
   • Includes viral URI (39%), sinusitis (9%), streptococcal pharyngitis (9%) 7

Immediate Management Algorithm

Step 1: Rapid Clinical Assessment (First 5 Minutes)

Check for these RED FLAGS indicating life-threatening pathology:

• Fever → strongly suggests CNS infection 1, 5
• Altered mental status or confusion → meningitis/encephalitis 1
• Nuchal rigidity or photophobia → meningitis 1
• Focal neurological signs (weakness, cranial nerve palsies, ataxia) → stroke, tumor, abscess 2, 5, 7
• Papilledema on fundoscopy → increased ICP 4, 8
• Inability to describe quality of pain → associated with serious disease 5, 7
• Occipital location of headache → statistically significant for dangerous conditions 5, 7
• Age <6 years → higher risk of serious pathology 4, 9
• Headache awakening from sleep → suggests increased ICP 4
• Seizures → encephalitis, tumor, hemorrhage 9

Step 2: Immediate Laboratory and Imaging (Within 30 Minutes)

If ANY red flags present:

1. Obtain blood cultures, CBC, hepatic transaminases, serum sodium BEFORE antibiotics 1

2. Neuroimaging BEFORE lumbar puncture if: 1

   • Focal neurological signs present
   • Altered consciousness
   • Concern for increased ICP (papilledema, severe vomiting)

3. Imaging choice: 2, 1

   • MRI brain with and without IV contrast is PREFERRED for suspected CNS infection 1
   • Shows superior sensitivity for encephalitis, meningeal enhancement, abscess 1
   • T2 FLAIR sensitive for vasogenic edema, DWI for cytotoxic edema 2, 1
   • Non-contrast CT acceptable if MRI unavailable or immediate imaging needed 2, 1
   • CT has 98% sensitivity for acute hemorrhage 1

4. If vertigo prominent and imaging initially normal: 6

   • Obtain dedicated MR venography (MRV) with contrast or CT venography to exclude cerebral venous thrombosis 6
   • Standard MRI can miss venous thrombosis 6

5. Lumbar puncture after imaging (if safe): 1

   • Opening pressure, glucose, protein, cell count, Gram stain, culture
   • Lymphocytic pleocytosis suggests viral encephalitis or ADEM 1

Step 3: Empiric Treatment (Do NOT Delay)

If CNS infection suspected (fever + headache + vomiting ± altered mental status):

• Start empiric IV antibiotics immediately—do NOT wait for LP or imaging if patient unstable 1
• Age-appropriate broad-spectrum coverage (typically ceftriaxone + vancomycin)
• Add acyclovir if encephalitis suspected (altered mental status, seizures) 1

Symptomatic management while awaiting diagnosis:

• IV antiemetics for nausea/vomiting control 6
• IV fluids for hydration
• Analgesics (ibuprofen most effective in pediatric headache) 9

Step 4: Disposition Based on Findings

Admit to hospital if:

• Any red flag present 4, 9
• Abnormal neuroimaging 2, 5
• Suspected CNS infection 1
• Significant intracranial pathology requiring neurosurgical evaluation 2

Consider observation/discharge only if:

• No red flags present
• Normal neurological examination
• Normal neuroimaging (if obtained)
• Symptoms consistent with benign cause (migraine, viral URI)
• Reliable follow-up available 9

Critical Pitfalls to Avoid

1. Do NOT assume normal initial MRI excludes cerebral venous thrombosis—dedicated venography is required 6

2. Do NOT delay antibiotics while awaiting imaging or LP in unstable patients with suspected meningitis 1

3. Do NOT dismiss vertigo as benign vestibular neuritis without excluding central causes, especially if focal neurological signs present 2, 3

4. Do NOT attribute headache to migraine if fever is present—fever is NOT typical of primary migraine 1

5. Do NOT rely on treatment response to determine need for imaging—analgesic failure alone is not an indication for neuroimaging 4

6. Do NOT overlook occipital headache location—this has statistically significant correlation with dangerous conditions 5, 7

7. Do NOT miss subtle neurological signs—all children with surgically remediable conditions had objective neurological signs 7

8. Do NOT perform LP before imaging if focal signs, altered consciousness, or papilledema present—risk of herniation 1