Thanks to Arathi for presenting the case of a middle-aged man with poorly controlled diabetes who presented with blurry vision and ear pain, found to have multiple cranial nerve palsies, diagnosed with skull base osteo, septic dural sinus thrombosis, and orbital cellulitis!

Clinical Pearls

• Septic thrombophlebitis is venous thrombosis with inflammation in the setting of bacteremia and can impact any vein.  Most common cause of this condition in the hospitalized patient is indwelling lines and catheters.
  • Septic thrombophlebitis of the jugular vein is called Lemierre’s syndrome and is frequently preceded by pharyngitis.
• Septic dural sinus thrombosis is extremely rare (only several hundred cases diagnosed in recent history).  The most common presenting symptom is headache.  There are three types:
  1. Cavernous sinus thrombosis
  2. Lateral (transverse) sinus thrombosis (rare)
  3. Superior sagittal sinus thrombosis (very rare)
• Cavernous sinus thrombosis can present with CN III, IV, V1, V2, VI palsies.  Of these, CN VI is the first one to get affected.  So for patients presenting with lateral gaze palsy and headache, think cavernous sinus thrombosis!
• The mainstay of treatment for septic dural sinus thrombosis is antibiotics.  Most common organism involved is staph aureus.
  • The role of anticoagulation is controversial.  The few retrospective studies done have shown a potential reduction in mortality/morbidity without a significant increase in risk of ICH.  Common practice currently is to start anticoagulation with heparin early on especially in patients with unilateral symptoms.

Septic dural sinus thrombosis

• Uncommon disease with only several hundred cases reported in the antibiotic era. So you might only see one in your whole career!
• Difficult to diagnose and often diagnosis and treatment are delayed.
• Encompasses three basic syndromes: manifestations of each are unique
  1. Cavernous sinus thrombosis
  2. Lateral sinus thrombosis
  3. Superior sagittal sinus thrombosis
• All three manifest as severe headaches which are often the presenting symptom.

Septic cavernous sinus thrombosis

• Most common. Lots of trabeculae to trap bacteria.
• Clinical manifestations
  • Headache and cranial nerve palsies should raise your suspicion!
  • Fever, periorbital edema. Pain is usually unilateral, retroorbital and frontal in nature with radiation to the occiput.
  • Diplopia
  • Altered mental status especially in older people
  • Less common: photophobia, tearing, and ptosis
• Exam:
  • Fever
  • B/l ptosis, proptosis, chemosis, and ocular muscle paralysis but can be subtle
  • Fundoscopic exam with papilledema
  • Ophthalmoplegia
    • Lateral gaze palsy (isolated CN VI) is the first manifestation because of the location of the nerve in the cavernous sinus.
  • Loss of visual acuity from papilledema
  • Compression of optic nerve by mycotic aneurysm of the intercavernous segment of the internal carotid/ophthalmic artery can lead to blindness.
• Labs:
  • CSF can show inflammatory cells in 75% of cases.
  • Micro
    • Staph aureus is the most common (70%) followed by strep and anaerobes.
  • Imaging:
    • CT venogram or MR venogram
  • Treatment
    • Antibiotics: IV and prolonged for at least 3 weeks b/c thrombus may prevent abx penetration
    • Anticoagulation: No prospective data. One retrospective study showed a significant reduction in mortality in patients with unilateral involvement who presented early and received heparin. A second showed no change in mortality but decreased morbidity.  No increased risk of ICH.  Based on these small studies, experts suggest heparin early on in patients with unilateral CST.  Duration of anticoagulation is at the discretion of the clinician (no data).
    • Surgery: Drainage of sinus infection if present, otherwise no benefit.
    • No role for steroids
• Outcomes
  • Mortality is 30%
  • Infection can spread to meninges and the pituitary and morbidity can reach 50%.
  • 30% suffer serious sequelae:
    • Persistent oculomotor weakness
    • Blindness
    • Hemiparesis
    • Pituitary insufficiency

Septic lateral sinus thrombosis

• Rare due to early treatment of otitis media. Generally results from untreated OM à mastoiditis à lateral sinus thrombosis.
• Earache is generally the first symptom for several weeks

Septic superior sagittal sinus thrombosis

• Extremely rare
• Usually due to bacterial meningitis
• Complete thrombosis is universally fatal.

Differential for cavernous sinus obstruction:

• Infectious
  • fungal
  • TB
  • septic thrombosis
  • intra-orbital abscess
• autoimmune/rheum
  • Tolosa-Hunt syndrome (granulomatous inflammation of the superior orbital vein and cavernous sinus)
  • Polyarteritis nodosa (Cogan syndrome)
  • sarcoid
  • IgG4 dz
  • GPA
• malignant
  • Lymphoma
  • Nasopharyngeal tumor
• Vascular
  • Thrombus

Skull base osteomyelitis:

• Frequently seen in elderly patients with poorly controlled diabetes or immunocompromise
• Most commonly a complication of malignant otitis externa.
• Results in multiple cranial nerve palsies VII through XII due to involvement of the stylomastoid, jugular, and hypoglossal foramens.
• Treatment requires antibiotics for at least 4-6 weeks.