Subdural Empyema complicating Subdural Empyema complicating Sinusitis in Immunocompetent adultsSinusitis in Immunocompetent adults

AuthorsInstitutions

Introduction Bacterial sinusitis is a common infection in

adults

Posterior invasion through sinus walls causes subdural empyema

Prompt neurosurgery and antibiotics are needed for successful treatment

We report two causes of subdural empyema in patients who had sinusitis as underlying cause

Case One

30 year old male was admitted via ER

Two weeks h/o head ache

Two days h/o intermittent fever, vomiting, facial twitching and tenderness over frontal region of head

Background Was seen in ER 3 days prior with headache

and fever

Febrile, no nuchal rigidity

Had CT head – Pansinusitis

Discharged with amoxicillin-clavulunate

Did not take antibiotics for two days due to lack of insurance

CT on first ER visit

Other History

PMH: Migraine, remote h/o seizure

PSH: None

Social: Non-smoker, no alcohol use

Family: None significant

Medications: None

Physical Exam

Temp 37.9o C, BP 90/49, PR 52

Drowsy, symmetrical facial twitching and nose wrinkling

Tenderness over frontal sinuses

Mild neck stiffness

Investigations

WBC 17.7

CSF: 295 WBC, protein 104, glucose 67

MRI scan of head

MRI

Management Commenced on cefotaxime, vancomycin,

metronidazole

Debridement of subdural empyema

Cultures grew viridans Streptococcus

Developed seizures and hemiplegia - repeat debridement with craniectomy

Treated with 6 weeks ABX, with resolution of hemiplegia

Case Two 55 year old male

Does not routinely seek medical care

Feeling generally unwell for few weeks

Took few doses of Levofloxacin given by physician friend

Was having intermittent headache, fever and increasingly lethargic

Seen previous day in urgent care, advised to follow with PCP

History continued

Came again with lethargy for 16 hrs, f/b decreased consciousness

PMH : Asthma

PSH: Nasal surgery and knee surgery

Social: Non smoker, no alcohol use

Medications: Advair and Fluticasone

Physical Examination

Temperature 36.8o C, PR 91, BP 125/71

Did not follow commands, obtunded

Mild menigismus

No grimace on percussion over sinuses

Moderate gingivitis

Investigations

Na 127

WBC 20.9

CT brain

CT scan

Management

Commenced on cefotaxime, vancomycin and metronidazole

Emergent fronto-parietal subdural evacuation

Functional endoscopic sinus surgery

Culture of the subdural empyema grew Streptococcus intermedius

Good recovery and was transferred to rehabilitation

Conclusion

Subdural empyema is uncommon but potentially fatal complication of sinusitis.

Suspect subdural empyema in patients with sinusitis plus any of the following:-altered mental status-nuchal rigidity-seizures-focal neurological changes.

MRI is more sensitive than CT for diagnosis.

CT scan & Subdural Empyema

In early stages small subdural empyema can be subtle in non-contrast CT

Subdural empyema do not cross the midline

Have crescent like configurations

It appears iso-attenuation to low attenuation extra axial collections compared to brain parenchyma with rim enhancement

MRI & Subdural Empyema Study of choice for detecting subdural empyema

Higher sensitivity of detection of small subdural fluid collections

Iso-intense signals on T1-weighted imaging

High signals on T2- weighted imaging

Can help to differentiate between subdural empyema from chronic subdural hematomas

( Low signal on T1WI vs. High signal on T1WI)

References

Ziai WC, Lewin JJ 3rd. Update in the diagnosis and management of central nervous system infections. Neurol Clin. 2008 May; 2(2): 427-68, viii.

Foerster BR, Thurnher MM, Malani PN et al. Intracranial infections: clinical and imaging characteristics. Acta Radiol. 2007 Oct; 48(8): 875-93.

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