BRAIN ABSCESSBRAIN ABSCESS
M.RASOOLINEJAD, MDM.RASOOLINEJAD, MDDEPATMENT OF INFECTIOUS DISEASEDEPATMENT OF INFECTIOUS DISEASE
TEHRAN UNIVERSITY OFTEHRAN UNIVERSITY OFMEDICAL SCIENCEMEDICAL SCIENCE
BRAIN ABSCESSBRAIN ABSCESS
Focal Focal & &
Suppurative Process Suppurative Process in Brain Parenchymain Brain Parenchyma
Anatomical Relationships of the MeningesAnatomical Relationships of the Meninges
•BoneBone
•Dura MaterDura Mater
•ArachnoidArachnoid
•Pia MaterPia Mater•BrainBrain
•Epidural AbscessEpidural Abscess
•Subdural EmpyemaSubdural Empyema
•MeningitisMeningitis
EPIDEMIOLOGYEPIDEMIOLOGY•Uncommon intracranial infectionsUncommon intracranial infections
•Incidence 1:100,000/yearIncidence 1:100,000/year
•Predisposing conditions: Paranasal SinusitisPredisposing conditions: Paranasal Sinusitis Otitis MediaOtitis Media Dental infectionsDental infections
•Immunocompromised ptsImmunocompromised pts Uncommon org Uncommon org(T.gondii, Aspergillus spp, Nocardia spp, …)(T.gondii, Aspergillus spp, Nocardia spp, …)
ETHIOLOGYETHIOLOGYAA brain abscess may develop:brain abscess may develop:1.1.Direct spread from a contagious cranial of infectionsDirect spread from a contagious cranial of infections( ( Paranasal sinusitis, Otitis media, Mastoiditis,…..)Paranasal sinusitis, Otitis media, Mastoiditis,…..)
2. 2. Following head trauma or Neurological procedureFollowing head trauma or Neurological procedure
3. 3. Hematogenous spread from remote site of infHematogenous spread from remote site of inf
4. 4. No obivious primary source of inf ( 20-30% )No obivious primary source of inf ( 20-30% ) (Cryptogenic brain abscess )(Cryptogenic brain abscess )
ETHIOLOGYETHIOLOGYMost common organisms are :Most common organisms are :•Paranasal sinusitis:Microaerophilic &Paranasal sinusitis:Microaerophilic & Anaerobic strepAnaerobic strep Haemophilus sppHaemophilus spp Bacteroides sppBacteroides spp Fusobacterium sppFusobacterium spp•Dental infections: Streptococci sppDental infections: Streptococci spp PrevetellaPrevetella ProphyromanasProphyromanas
ETHIOLOGYETHIOLOGYMost common organisms are :Most common organisms are :Otitis media & Mastoiditis:Otitis media & Mastoiditis: StreptococciStreptococci Bacteroides sppBacteroides spp P. aeroginosaP. aeroginosa EnterobacteriaceaeEnterobacteriaceaeHematogenous: S. ViridanceHematogenous: S. Viridance S. AureousS. AureousNeurosergical procedure & open head traumaNeurosergical procedure & open head trauma::(S. aureous, Enterobactericeae, P. aeroginosa)(S. aureous, Enterobactericeae, P. aeroginosa)
SOURSE OF BRAIN ABSCESSSOURSE OF BRAIN ABSCESS•Frontal lobe:Frontal lobe: Frontal & Ethmoidal & Sphenoidal sinusesFrontal & Ethmoidal & Sphenoidal sinuses Dental infectionsDental infections
•Temporal lobeTemporal lobe: : Middle ear, Mastoid, Maxillary sinusesMiddle ear, Mastoid, Maxillary sinuses
•Cerebellum & Brain Stem: Middle ear & MastoidCerebellum & Brain Stem: Middle ear & Mastoid
•Posterior Frontal or Parietal lobes:Posterior Frontal or Parietal lobes: Middle Cerebral ArteryMiddle Cerebral Artery Gray- White matterGray- White matter Often multipleOften multiple
PATHGENESISPATHGENESIS•Bacterial invasion of brainBacterial invasion of brain (Parenchyma )(Parenchyma )•Preexisting or concomitant :Preexisting or concomitant : Ischemia &Ischemia & Necrosis & Necrosis & Hypoxia of brain tissueHypoxia of brain tissue
PATHGENESISPATHGENESIS4 Stages Brain Abscess formation:4 Stages Brain Abscess formation:
Early cerebritis ( days 1 to 3 )Early cerebritis ( days 1 to 3 )
Prevascular infiltration of inflammatory cellsPrevascular infiltration of inflammatory cells
Central core of coagulative necrosis Central core of coagulative necrosis
Marked edema surrounds the lesionsMarked edema surrounds the lesions
Stage 1 Stage 1
PATHGENESISPATHGENESIS4 Stages Brain Abscess formation:4 Stages Brain Abscess formation:
Late cerebritis ( days 4 to 9 )Late cerebritis ( days 4 to 9 ) Pus formation ( necrotic center )Pus formation ( necrotic center ) Macrophages & Fibroblastrs Macrophages & Fibroblastrs Thin capsule Thin capsule ( Fibroblast & Reticular fibers )( Fibroblast & Reticular fibers ) Marked edema around the lesions Marked edema around the lesions
Stage 2Stage 2
PATHGENESISPATHGENESIS4 Stages Brain Abscess formation:4 Stages Brain Abscess formation:
Early Capsule formation ( days 10 to13 )Early Capsule formation ( days 10 to13 ) Capsule formationCapsule formation
Ring-enhancing capsule ( Imaging )Ring-enhancing capsule ( Imaging )
Stage 3Stage 3
PATHGENESISPATHGENESIS4 Stages Brain Abscess formation:4 Stages Brain Abscess formation:
Stage 4 Stage 4 Late Capsule formation ( > 14 days )Late Capsule formation ( > 14 days ) Well formed necrotic centerWell formed necrotic center Dense peripheral collagenous capsuleDense peripheral collagenous capsule No cerebral edemaNo cerebral edema Marked gliosis & reactive astrocytesMarked gliosis & reactive astrocytes Gliosis Gliosis Seizures Seizures
CLINICAL PRESENTATIONSCLINICAL PRESENTATIONSBrain abscess presents as an Brain abscess presents as an Expanding Intracranial massExpanding Intracranial mass
Headache > 75%Headache > 75% Constant, Dull, Constant, Dull, Aching sensationAching sensation Hemicranial or General Hemicranial or General Progressive Progressive Refractory RefractoryFever: 50% & Low gradeFever: 50% & Low gradeSeizure: New onset Seizure: New onset Focal or GeneralizedFocal or Generalized
CLINICAL PRESENTATIONSCLINICAL PRESENTATIONS
Increased Intracranial Pressure:Increased Intracranial Pressure:•PapilledemaPapilledema•NauseaNausea•VomitingVomiting•DrowsinessDrowsiness•ConfusionConfusionMeningismus:Meningismus:•When it has ruptured into When it has ruptured into Ventricle or subarachnoid spaceVentricle or subarachnoid space
CLINICAL PRESENTATIONSCLINICAL PRESENTATIONS
Focal neurologic deficit > 60%Focal neurologic deficit > 60%•Frontal lobeFrontal lobe Hemiparesis Hemiparesis Mental status, DrowsinessMental status, Drowsiness
•Temporal lobeTemporal lobe Dysphasia DysphasiaUpper homonymous quadrantanopiaUpper homonymous quadrantanopiaIpsilateral headacheIpsilateral headache
CLINICAL PRESENTATIONSCLINICAL PRESENTATIONS
Focal neurologic deficit > 60%Focal neurologic deficit > 60%•Cerebellar Cerebellar Nystagmus, Ataxia Nystagmus, Ataxia Dysmetria, vomiting Dysmetria, vomiting
•Brain stemBrain stem Facial weakness, Facial weakness,Fever, Hemiparesis, Dysphagia,Fever, Hemiparesis, Dysphagia,Vomiting, Headache, Fever Vomiting, Headache, Fever
DIAGNOSISDIAGNOSISNEUROIMAGING STUDIESNEUROIMAGING STUDIES
•Brain CT- ScanBrain CT- Scan•MRI ( Early cerebritis, Posterior Fossa)MRI ( Early cerebritis, Posterior Fossa)•Steriotactic Needle aspirationSteriotactic Needle aspiration•Lumbar puncture Lumbar puncture Risk of Herniation Risk of Herniation•CSF CSF Non Specific Non Specific•Peripheral leucocytosis: 50%Peripheral leucocytosis: 50%•Elevated ESR: 60%Elevated ESR: 60%
TREATMENTTREATMENTSURGICOMEDICAL SURGICOMEDICAL
•Aspiration Or Open DrainageAspiration Or Open Drainage•Empirical Combination Empirical Combination Antimicrobial TherapyAntimicrobial Therapy•Duration: 6 to 8 wks IVDuration: 6 to 8 wks IV•Prophylactic Anticonvulsant Prophylactic Anticonvulsant TherapyTherapy•GlucocorticoidsGlucocorticoids( Severe Edema & ICP )( Severe Edema & ICP ) •Serial CT-Scan or MRISerial CT-Scan or MRI
ANTIMICROBIAL THERAPYANTIMICROBIAL THERAPYOtitis media Otitis media && Mastoiditis: Mastoiditis:Metronodazole Metronodazole && 3 3rdrd Cephalosporin Cephalosporin
Sinusitis:Sinusitis:Metronidazole Metronidazole && 3 3rdrd Cephalosporine Cephalosporine
Dental Sepsis:Dental Sepsis:Penicillin & MetronidazolePenicillin & Metronidazole
ANTIMICROBIAL THERAPYANTIMICROBIAL THERAPYPenetrating trauma Penetrating trauma &&Neurosurgury:Neurosurgury:Vancomycin Vancomycin && 3 3rdrd Cephalosporin Cephalosporin
Bacterial endocarditis:Bacterial endocarditis:Vancomycin & Gentamycin Vancomycin & Gentamycin Nafcilline (Oxacillin) & Ampicillin Nafcilline (Oxacillin) & Ampicillin & Gentamycin& GentamycinUnknown: Unknown: Vancomycin Vancomycin && Metronidazole Metronidazole && 33rdrd Cephalosporin Cephalosporin
PROGNOSISPROGNOSIS
Successfully treatment Successfully treatment Good prognosisGood prognosis
Seizures are a Seizures are a common complication 70%common complication 70%