**Patient Information:**  
Name: Mr Patient  
Age: 13 years  
Gender: Male  
Medical History: Not specified (entry "dfgdfg" appears non-informative)

**Presenting Symptom:**  
Headache

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### 1. Potential Differential Diagnoses

In a 13-year-old male presenting with headache, consider the following common and serious causes:

**Primary Headache Disorders:**
- Migraine (with or without aura)
- Tension-type headache
- Cluster headache (less common in this age group)

**Secondary Headache Causes:**
- Viral or bacterial infection (e.g., sinusitis, upper respiratory tract infection, meningitis)
- Medication overuse headache
- Head trauma/concussion
- Vision problems (refractive errors)
- Dental issues (e.g., temporomandibular joint dysfunction)
- Intracranial pathology (e.g., tumor, hydrocephalus, idiopathic intracranial hypertension)
- Hypertension
- Dehydration

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### 2. Recommended Diagnostic Tests

**Initial Evaluation:**
- Comprehensive history and physical examination, including neurological assessment
- Vital signs (including blood pressure)
- Fundoscopic examination (to assess for papilledema)

**Further Investigations (if indicated by history/exam):**
- CBC, CRP/ESR (if infection or inflammation suspected)
- Lumbar puncture (if meningitis or subarachnoid hemorrhage suspected)
- Neuroimaging (CT/MRI brain) if:
  - Abnormal neurological findings
  - Sudden onset ("thunderclap" headache)
  - Signs of raised intracranial pressure
  - Headache awakens patient from sleep or is worse in the morning
  - New onset severe headache
- Sinus imaging (if sinusitis suspected)
- Vision assessment (if visual symptoms present)

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### 3. Urgency Level

**Medium** (based on current information)

- **Low** if headache is mild, intermittent, with no red flags, and normal exam.
- **High** if any red flags (see below) are present.

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### 4. Key Observations and Clinical Notes

- **History:** Onset, duration, location, character, severity, associated symptoms (nausea, vomiting, photophobia, phonophobia, visual changes, neck stiffness, fever, recent trauma, focal neurological deficits, recent illness).
- **Family history:** Migraine or other headache disorders.
- **Medication history:** Recent changes, over-the-counter or prescription drugs.
- **Social history:** School stress, screen time, sleep patterns.
- **Physical exam:** General appearance, vital signs, neurological exam, fundoscopic exam, sinus tenderness, neck stiffness.

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### 5. Red Flags to Watch For

- Sudden, severe ("worst ever") headache
- Headache with fever, neck stiffness, photophobia (meningitis)
- Altered mental status, confusion, seizures
- Focal neurological deficits (weakness, vision loss, ataxia)
- Papilledema (signs of raised intracranial pressure)
- Headache that awakens from sleep or is worse in the morning
- Recent head trauma
- Persistent vomiting
- Immunosuppression or known malignancy

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**Clinical Note:**  
Given the limited information, a thorough history and physical examination are essential to guide further workup. If any red flags are present, urgent evaluation is warranted. Otherwise, outpatient management and monitoring may be appropriate.

**Recommendation:**  
Advise prompt evaluation by a healthcare professional to further characterize the headache and rule out serious causes.