II. Precautions
- Headache location does not differentiate cause in HIV patients
- HIV patients typically present without meningeal signs despite underlying Meningitis
- HAART has decreased Incidence of opportunistic infection causes of Headache- However HIV patients require a high level of vigilence in evaluation due to confounding factors
 
III. Differential Diagnosis
- Primary HIV related Headaches- Aseptic HIV Meningitis- Often self-limited, presenting at any HIV Stage
 
- Chronic HIV Meningitis- Presents as persistent moderate Tension Headache-like symptoms
 
 
- Aseptic HIV Meningitis
- Secondary HIV related Headaches- Opportunistic Meningitis- Cryptococcal Meningitis- Common cause of Headache in AIDS patients and uniformly lethal if untreated
- Bilateral occipital and bifrontal Headaches
 
- Tuberculous Meningitis
- Meningovascular Syphilis
 
- Cryptococcal Meningitis
- Malignant Meningitis- Lymphomatous Meningitis
 
- Focal Brain Lesions- Brain Abscess
- Primary CNS Lymphoma
- Progressive Multifocal Leukoencephalopathy (PML)- Common cause of Headache in AIDS patients
- Bifrontal and diffuse Headaches
 
 
- Diffuse Brain Lesions- HSV Encephalitis- Common cause of Headache in AIDS patients
 
- CMV Encephalitis
- Toxoplasmosis
 
- HSV Encephalitis
 
- Opportunistic Meningitis
- Non-HIV related Headaches- See Medication Causes of Headache (includes Zidovudine)
- Meningitis- Bacterial Meningitis (especially Pneumococcal Meningitis)- Relative Risk of Bacterial Meningitis in HIV is 19 fold higher than the general population
- Higher risk with CD4 Count <200 cells/mm3, without Pneumococcal Vaccine, and comorbid Cirrhosis or cancer
- Often presents with focal neurologic deficit and without meningeal signs
 
- Viral Meningitis
 
- Bacterial Meningitis (especially Pneumococcal Meningitis)
- Non-CNS InfectionHeadaches- Acute Sinusitis
- Migraine Headache or Tension Headache- Most common Headache Causes in outpatient HIV patients on HAART
- Headaches routinely occur in 50% of HIV patients and most of these are Migraine Headaches
- Migraine Headaches increase in Incidence with decreasing CD4 Counts
- Kirkland (2012) Headache 52(3): 455-66 [PubMed]
 
 
 
IV. Imaging
- Indications- Serious HIV Headache Red Flags (CD4<200/mm3 or concerning Headache findings)
 
- Modalities- MRI Brain or
- CT Head with contrast- Obtain without contrast first if risk of CNS Hemorrhage
 
 
- Findings- See Brain Lesion in HIV
- Enhancing Brain Lesions- Toxoplasmosis
- Primary CNS Lymphoma
 
- Non-enhancing Brain Lesions
- Brain Lesion absent
 
V. Labs: Lumbar Puncture
- Indications- Serious HIV Headache Red Flags (CD4<200/mm3 or concerning Headache findings)
- Non-diagnostic imaging
 
- Contraindications- See Lumbar Puncture
- Consider serum markers if Lumbar Puncture contraindicated- Cryptococcal Antigen has very high Test Sensitivity
 
 
- CSF Labs- Opening pressure- Important in diagnosis of Cryptococcal Meningitis
- Cryptococcal Meningitis is associated with opening pressure >350 mm H2O
 
- Standard CSF Tests- CSF Cell Count and differential
- CSF Protein- Low yield (frequently normal despite CNS Infection in HIV)
 
- CSF Glucose- Low yield (frequently normal despite CNS Infection in HIV)
 
 
- Cultures and stains- Bacterial Culture
- Fungal Culture
- India Ink Stain
 
- Specific organism testing- Cryptococcal Antigen
- Toxoplasma PCR
- Epstein-Barr Virus PCR (EBV PCR)
- John Cunningham Virus PCR (JCV PCR)
- Cytomegalovirus PCR (CMV PCR)
- Herpes Simplex Virus PCR (HSV PCR)
- VDRL
 
 
- Opening pressure
VI. Evaluation: Serious HIV Headache Red Flags
- Findings suggestive of AIDS with CD4<200 cells/mm3- AIDS-Defining Illness
- Absolute Lymphocyte Count <1000 cells/mm3
 
- Concerning Headache findings- Fever
- New or changing Headache
- Altered Mental Status
- Seizure
- Focal neurologic changes
 
- Approach- Consult infectious disease
- Neuroimaging and
- Lumbar Puncture (if not contraindicated)
 
VII. Evaluation: Low risk findings
- Stage 1 HIV- See HIV Staging
- No history of AIDS-Defining Illness
- CD4 Count >500 Cells/mm3- As alternative (if CD4 Count not known): Absolute Lymphocyte Count >2000 cells/mm3
- See Absolute Lymphocyte Count Estimation of CD4 Count
 
 
- Stage 2 HIV (with caution)- Known recent CD4 Count >200 Cells/mm3 and CD4 percentage >15%- As alternative (if CD4 Count not known): Absolute Lymphocyte Count >2000 cells/mm3
- See Absolute Lymphocyte Count Estimation of CD4 Count
 
- No history of AIDS-Defining Illness
- No comorbidities (e.g. Hepatitis C)
- HAART Therapy (Compliant and not recently initiated)- Not required but significantly decreases risk of opportunistic CNS Infection
 
 
- Known recent CD4 Count >200 Cells/mm3 and CD4 percentage >15%
- Low-risk Headache (uncomplicated)- Headache is not new or changing
- No fever or meningismus
- Normal sensorium
- No Seizure
- No focal neurologic deficits- No Hearing Loss or Vision Loss
- No Cranial Nerve deficit
 
 
- Other findings suggestive of uncomplicated Headache (e.g. Sinusitis, Migraine Headache, Tension Headache)- Unilateral, abrupt onset Headache with photophobia
- No associated focal weakness or Paresthesias
- Other findings do not distinguish Headache cause (Nausea or Vomiting, Blurred Vision or confusion)
 
- Approach- Consider Consultation with infectious disease
- Close interval follow-up with precautions
- Treat suspected Headache cause
 
VIII. References
- Perkins (2013) Crit Dec Emerg Med 27(3): 2-9
- Kirkland (2012) Headache 52(3): 455-66 [PubMed]
