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

**Current Symptom:**  
Headache

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### 1. Potential Differential Diagnoses

In a 13-year-old male presenting with headache, differentials include:

- **Primary Headaches:**
  - Migraine (with or without aura)
  - Tension-type headache
  - Cluster headache (less common at this age)

- **Secondary Headaches:**
  - Viral or bacterial infection (e.g., sinusitis, upper respiratory tract infection, meningitis/encephalitis)
  - Medication overuse or withdrawal
  - Head trauma (concussion, subdural/epidural hematoma)
  - Vision problems (refractive errors)
  - Intracranial mass lesion (tumor, abscess, hydrocephalus)
  - Hypertension
  - Idiopathic intracranial hypertension

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### 2. Recommended Diagnostic Tests

The choice of tests depends on further history and physical findings. Initial recommendations:

- **History & Physical Exam:** Detailed neurological and general physical examination
- **Basic Investigations:**
  - Vital signs (including blood pressure)
  - Fundoscopy (to assess for papilledema)
  - Visual acuity testing
- **If red flags or abnormal findings:**
  - Neuroimaging (CT/MRI brain)
  - Lumbar puncture (if meningitis, encephalitis, or subarachnoid hemorrhage suspected)
  - Laboratory tests (CBC, CRP, ESR, electrolytes)

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### 3. Urgency Level

- **Medium** (based on isolated headache and lack of red flag symptoms in the provided information)
- **High** if any red flags are present (see below)

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### 4. Key Observations and Clinical Notes

- The symptom is non-specific: further history is essential (onset, duration, quality, associated symptoms, triggers, family history, medication use, trauma, recent infections).
- No mention of fever, neck stiffness, vomiting, visual changes, or altered consciousness.
- No prior medical history provided.
- Headaches in this age group are often benign but secondary causes must be ruled out, especially with new, severe, or progressive symptoms.

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### 5. Red Flags to Watch For

- Sudden, severe (“thunderclap”) headache
- Headache with fever, neck stiffness, photophobia (concern for meningitis/encephalitis)
- Altered mental status, confusion, or seizures
- Focal neurological deficits (weakness, numbness, vision loss)
- Papilledema or signs of increased intracranial pressure (vomiting, worse lying down)
- Headache waking patient from sleep
- Recent head trauma
- Immunocompromised state or known malignancy

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### 6. Confidence Level

**Confidence Level:** 70%  
*Rationale: The analysis is based on a single, non-specific symptom with insufficient clinical context or history. Confidence would increase with a more detailed history and examination findings.*

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**Note:**  
This analysis is intended to guide further assessment and is not a substitute for direct clinical evaluation. Prompt review by a healthcare professional is recommended to obtain a thorough history, perform an examination, and determine appropriate management.