Drug induced aseptic meningitis

Background

• Abbreviation: DIAM
• Two proposed mechanisms
  • Direct meningeal irritation by intrathecal drug
  • Hypersensitivity reaction to drug (type III and IV)
• Higher predominance in SLE and female gender

Causes

• NSAIDs
  • Most common cause
• Antibiotics
  • Sulfamethizole
  • TMP-SMX
  • Isoniazid
  • Ciprofloxacin
  • Amoxicillin
  • Gentamicin
  • Penicillin
  • Metronidazole
  • Cephalosporins
  • Pyrazinamide
• Immunoregulating agents
  • IVIGs
  • OKT3 monoclonal antibodies
• Misc
  • Sulfasalazine
  • Carbamazepine
  • Azathioprine
  • Indinavir
  • Valacyclovir
  • Ranitidine
  • Famotidine
  • Methylprednisolone acetate
  • Allopurinol

Clinical Freatures

Symptoms generally occur within 24-48 hours after taking drug

• Headache
• Fever
• Nuchal rigidity
• Nausea/vomiting
• General malaise
• Altered mental status
• Less common symptoms include rash, arthralgia, myalgia, facial edema

Differential Diagnosis

Headache

Common

• Migraine headache
• Tension headache
• Cluster headache

Killers

• Meningitis/encephalitis
  • Neoplastic meningitis
• Myocardial ischemia
• Retropharyngeal abscess
• Intracranial Hemorrhage (ICH)
  • SAH / sentinel bleed
• Acute obstructive hydrocephalus
• Space occupying lesions
• CVA
• Carbon monoxide poisoning
• Basilar artery dissection
• Preeclampsia
• Cerebral venous thrombosis
• Hypertensive emergency
• Depression

Maimers

• Giant cell arteritis of temporal artery (temporal arteritis)
• Idiopathic intracranial hypertension (Pseudotumor Cerebri)
• Acute Glaucoma
• Acute sinusitis
• Cavernous sinus thrombosis or cerebral sinus thrombosis
• Carotid artery dissection

Others

• Trigeminal neuralgia
• TMJ pain
• Post-lumbar puncture headache
• Dehydration
• Analgesia abuse
• Various ocular and dental problems
• Herpes zoster ophthalmicus
• Herpes zoster oticus
• Cryptococcosis
• Febrile headache (e.g. pyelonephritis, nonspecific viral infection)
• Ophthalmoplegic migraine
• Superior Vena Cava Syndrome

Aseptic Meningitis

• Viral
  • Varicella
  • Herpes
  • Enterovirus
  • West Nile
• Tuberculosis
• Lyme disease
• Syphilis
• Leptospirosis
• Fungal (AIDS, transplant, chemotherapy, chronic steroid use)
• Noninfectious
  • Sarcoidosis
  • Vasculitis
  • Connective tissue disease
  • Drug induced aseptic meningitis

Evaluation

• Drug history with focus on time of ingestion and symptom onset
• CSF studies
  • Pleiocytosis (primarily neutrophilic)
  • Elevated protein levels
  • Normal glucose
  • Negative cultures
• Challenge test with suspected drug
  • Only confirmatory test
  • Requires informed written consent
  • Due to associated risk, should only be done if suspected drug is irreplaceable

Management

• Discontinuation of offending agent

Outcome

• Generally good, usually with no long term sequelae

See Also

• Meningitis