Brain abscess: Difference between revisions
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==Background== | ==Background== | ||
[[File:Brainlobes.png|thumb|Lobes of the brain.]] | |||
*Caused by one of three methods: | *Caused by one of three methods: | ||
**Hematogenous spread (33%) | **Hematogenous spread (33%) | ||
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**Direct implantation by surgery or penetrating trauma (10%) | **Direct implantation by surgery or penetrating trauma (10%) | ||
*Microbiology | *Microbiology | ||
**Streptococci in 50% of cases<ref>Somand D, Meurer W. Central Nervous System Infections. EMCNA 2009; 27: 89-100.</ref> | **[[Streptococci]] in 50% of cases<ref>Somand D, Meurer W. Central Nervous System Infections. EMCNA 2009; 27: 89-100.</ref> | ||
**Anaerobes and Gram-negative rods are typical pathogens | **[[Anaerobes]] and [[Gram-negative]] rods are typical pathogens | ||
**Staph is involved with direct implantation cases | **[[Staph]] is involved with direct implantation cases | ||
==Clinical Features== | ==Clinical Features== | ||
*Patients rarely appear acutely ill | *Patients rarely appear acutely ill | ||
*Classic | *Classic triad of headache, fever, '''AND''' focal neuro deficit is present in <33% | ||
**Headache is most common symptom (present in almost all cases) | **[[Headache]] is most common symptom (present in almost all cases) | ||
**Fever (~50% of patients) | **[[Fever]] (~50% of patients) | ||
*Focal neuro symptoms or seizure (~33% of patients) | *[[Focal neuro]] symptoms or seizure (~33% of patients) | ||
*Neck stiffness (<50% of patients) | *Neck stiffness (<50% of patients) | ||
*Signs of increased ICP: papilledema, vomiting, confusion, obtundation (50% of patients) | *Signs of [[increased ICP]]: [[papilledema]], [[vomiting]], [[confusion]], [[coma|obtundation]] (50% of patients) | ||
==Differential Diagnosis== | ==Differential Diagnosis== | ||
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{{Intracranial mass DDX}} | {{Intracranial mass DDX}} | ||
{{AMS and fever DDX}} | |||
==Evaluation== | ==Evaluation== | ||
[[File:PMC4857327 10.1177 2050313X15591314-fig3.png|thumb|Brain abscess on CT (arrows) with left hemiplegia.]] | |||
[[File:PMC3970313 ic-46-45-g001.png|thumb|Nocardia brain abscess on MRI. (A) T1-WI shows rim-enhancing lesion with associated edema in the right occipital lobe. (B) The dark signal on T2-WI and consistent thickness of the wall suggest a brain abscess.]] | |||
*[[Head CT]] with contrast | *[[Head CT]] with contrast | ||
**Ring enhancing lesion surrounding low-density center surrounded by white matter edema | **Ring enhancing lesion surrounding low-density center surrounded by white matter edema | ||
**Early in course ring may be less defined; CT may only show area of focal hypodensity | **Early in course ring may be less defined; CT may only show area of focal hypodensity | ||
*[[Blood cultures]] | |||
*Consider additional workup to evaluate for alternate etiologies/complications of underlying disease process | |||
==Management== | ==Management== | ||
Latest revision as of 22:29, 25 January 2023
Background
- Caused by one of three methods:
- Hematogenous spread (33%)
- Contiguous infection from middle ear, sinus, teeth (33%)
- Direct implantation by surgery or penetrating trauma (10%)
- Microbiology
- Streptococci in 50% of cases[1]
- Anaerobes and Gram-negative rods are typical pathogens
- Staph is involved with direct implantation cases
Clinical Features
- Patients rarely appear acutely ill
- Classic triad of headache, fever, AND focal neuro deficit is present in <33%
- Focal neuro symptoms or seizure (~33% of patients)
- Neck stiffness (<50% of patients)
- Signs of increased ICP: papilledema, vomiting, confusion, obtundation (50% of patients)
Differential Diagnosis
- CVA
- Meningitis, encephalitis
- Malignancy
Intracranial Mass
- Intracranial hemorrhage
- Intra-axial
- Hemorrhagic stroke (Spontaneous intracerebral hemorrhage)
- Traumatic intracerebral hemorrhage
- Extra-axial
- Epidural hemorrhage
- Subdural hemorrhage
- Subarachnoid hemorrhage (aneurysmal intracranial hemorrhage)
- Intra-axial
- Brain tumor
- Brain abscess
- Subdural empyema
- Epidural abscess (intracranial)
Altered mental status and fever
- Infectious
- Sepsis
- Meningitis
- Encephalitis
- Cerebral malaria
- Brain abscess
- Other
Evaluation
- Head CT with contrast
- Ring enhancing lesion surrounding low-density center surrounded by white matter edema
- Early in course ring may be less defined; CT may only show area of focal hypodensity
- Blood cultures
- Consider additional workup to evaluate for alternate etiologies/complications of underlying disease process
Management
Antibiotics
Otogenic source
- Cefotaxime 2gm IV q6hr + metronidazole 500mg IV q6hr
Sinogenic or odontogenic source
- Cefotaxime 2gm IV q6hr + metronidazole 500mg IV q6hr
Penetrating trauma or neurosurgical procedures
- Vancomycin 15mg/kg IV q12hr + ceftazidime 2gm IV q8hr
Hematogenous source
- Cefotaxime 2gm IV q6hr + metronidazole 500mg IV q6hr
No obvious source
- Cefotaxime 2gm IV q6hr + metronidazole 500mg IV q6hr
Disposition
- Neurosurgery consultation
References
- ↑ Somand D, Meurer W. Central Nervous System Infections. EMCNA 2009; 27: 89-100.