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{{Epidural abscess}}
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==Overview==
==Overview==
According to the location of the epidural abscess, its pathophysiology will differ, particularly in the origin of the [[infection]] but also in [[symptoms]],  commonly causing organism, progression of the condition and therefore the treatment required.
Epidural abscess pathophysiology differs based on the location of the [[infection]] and responsible organism. The majority of intracranial epidural abscess cases occur as a complication of cranial surgical procedures and [[sinusitis]].<ref name="pmid15043336">{{cite journal| author=Fountas KN, Duwayri Y, Kapsalaki E, Dimopoulos VG, Johnston KW, Peppard SB et al.| title=Epidural intracranial abscess as a complication of frontal sinusitis: case report and review of the literature. | journal=South Med J | year= 2004 | volume= 97 | issue= 3 | pages= 279-82; quiz 283 | pmid=15043336 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15043336  }} </ref> The majority of spinal epidural abscess cases occur as a result of spinal instrumentation, vascular access, and [[IV drug use]].<ref name="pmid24340840">{{cite journal| author=Strauss I, Carmi-Oren N, Hassner A, Shapiro M, Giladi M, Lidar Z| title=Spinal epidural abscess: in search of reasons for an increased incidence. | journal=Isr Med Assoc J | year= 2013 | volume= 15 | issue= 9 | pages= 493-6 | pmid=24340840 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=24340840  }} </ref>
In the case of intracranial epidural abscess, it surges most frequently as a complication of cranial surgical procedures and [[sinusitis]], particularly paranasal [[sinusitis]], as the [[infection]] progresses intracranially. <ref name="pmid15043336">{{cite journal| author=Fountas KN, Duwayri Y, Kapsalaki E, Dimopoulos VG, Johnston KW, Peppard SB et al.| title=Epidural intracranial abscess as a complication of frontal sinusitis: case report and review of the literature. | journal=South Med J | year= 2004 | volume= 97 | issue= 3 | pages= 279-82; quiz 283 | pmid=15043336 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15043336  }} </ref>
On the other hand, spinal epidual abscess happens most frequently due to spinal instrumentation, vascular access and injection drug use. <ref name="pmid24340840">{{cite journal| author=Strauss I, Carmi-Oren N, Hassner A, Shapiro M, Giladi M, Lidar Z| title=Spinal epidural abscess: in search of reasons for an increased incidence. | journal=Isr Med Assoc J | year= 2013 | volume= 15 | issue= 9 | pages= 493-6 | pmid=24340840 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=24340840  }} </ref>


==Pathophysiology==
==Pathophysiology==
===Intracranial Epidural Abscess===
Epidural abscess pathophysiology differs based on the location of the [[infection]] and responsible organism.
Although less common than spinal epidural abscess and with a more indolent evolution, it also requires prompt diagnosis and treatment to avoid severe outcomes. Since intracranial [[dura mater]] is adherent to the inner table of the [[skull]], the so-called '''''[[epidural space]]''''' is actually a ''virtual space'', which can become a ''real space'' by increasing pressure from a liquid, such as [[pus]] or [[blood]]  or a solid mass, such as a [[tumor]].  This tight adherence contributes to the slow progression and typical round-shape appearance of the [[abscess]]. Because the [[dura mater]] is tightly attached to the [[skull]], in the area of the ''[[foramen magnum]]'', this [[abscess]] is usually restricted to the [[cranial cavity]].  On the periphery of the [[pus]] collection is created a wall of [[inflammation]],  which may calcify and therefore be identified in imaging studies. <ref name="pmid15043336">{{cite journal| author=Fountas KN, Duwayri Y, Kapsalaki E, Dimopoulos VG, Johnston KW, Peppard SB et al.| title=Epidural intracranial abscess as a complication of frontal sinusitis: case report and review of the literature. | journal=South Med J | year= 2004 | volume= 97 | issue= 3 | pages= 279-82; quiz 283 | pmid=15043336 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15043336  }} </ref><ref name="pmid14519222">{{cite journal| author=Heran NS, Steinbok P, Cochrane DD| title=Conservative neurosurgical management of intracranial epidural abscesses in children. | journal=Neurosurgery | year= 2003 | volume= 53 | issue= 4 | pages= 893-7; discussion 897-8 | pmid=14519222 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=14519222  }} </ref>


*Etiologies: <ref name="pmid15043336">{{cite journal| author=Fountas KN, Duwayri Y, Kapsalaki E, Dimopoulos VG, Johnston KW, Peppard SB et al.| title=Epidural intracranial abscess as a complication of frontal sinusitis: case report and review of the literature. | journal=South Med J | year= 2004 | volume= 97 | issue= 3 | pages= 279-82; quiz 283 | pmid=15043336 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15043336  }} </ref>
===Intracranial epidural abscess===
**Paranasal [[sinusitis]], particularly of the [[frontal sinuses]].
Intracranial epidural abscess is the result of sequelae of cranial surgical procedures, [[sinusitis]], and [[mastoiditis]]. Cranial [[dura mater]] is adherent to the inner table of the [[skull]] in the [[epidural space]]. This virtual space can become a real space by increasing pressure from a liquid, such as [[pus]] or [[blood]], or a solid mass, such as a [[tumor]]. A tight adherence contributes to the slow progression and typical round-shape appearance of the [[abscess]]. Because the [[dura mater]] is tightly attached to the [[skull]] in the [[foramen magnum]], intracranial epidural abscesses are usually restricted to the [[cranial cavity]]. On the periphery of the [[pus]] collection is a wall of [[inflammation]], which may calcify and is identifiable in imaging studies.<ref name="pmid15043336">{{cite journal| author=Fountas KN, Duwayri Y, Kapsalaki E, Dimopoulos VG, Johnston KW, Peppard SB et al.| title=Epidural intracranial abscess as a complication of frontal sinusitis: case report and review of the literature. | journal=South Med J | year= 2004 | volume= 97 | issue= 3 | pages= 279-82; quiz 283 | pmid=15043336 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15043336  }} </ref><ref name="pmid14519222">{{cite journal| author=Heran NS, Steinbok P, Cochrane DD| title=Conservative neurosurgical management of intracranial epidural abscesses in children. | journal=Neurosurgery | year= 2003 | volume= 53 | issue= 4 | pages= 893-7; discussion 897-8 | pmid=14519222 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=14519222  }} </ref>
**[[Osteomyelitis]] of the [[skull]] (possible association with ''Pott's Puffy Tumor''.
**Extension of [[infection]] from [[otitis]], [[mastoiditis]] or [[orbit]].
**Direct inoculation, during a [[surgical procedure]] or [[trauma]].
**''In pediatric population'': scalp venous catheter.
**Remote [[infection]] sites, through hematological spread.
**Possible association with exposure to expanded polytetrafluethylene.


*In the case of an intracranial epidural abscess originated in an [[infection]] site, such as [[sinusitis]], the organisms may reach the virtual [[epidural space]] by several means: <ref name="pmid15043336">{{cite journal| author=Fountas KN, Duwayri Y, Kapsalaki E, Dimopoulos VG, Johnston KW, Peppard SB et al.| title=Epidural intracranial abscess as a complication of frontal sinusitis: case report and review of the literature. | journal=South Med J | year= 2004 | volume= 97 | issue= 3 | pages= 279-82; quiz 283 | pmid=15043336 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15043336  }} </ref>
Pathophysiological pathways for the progression of intracranial epidural abscess include:<ref name="pmid15043336">{{cite journal| author=Fountas KN, Duwayri Y, Kapsalaki E, Dimopoulos VG, Johnston KW, Peppard SB et al.| title=Epidural intracranial abscess as a complication of frontal sinusitis: case report and review of the literature. | journal=South Med J | year= 2004 | volume= 97 | issue= 3 | pages= 279-82; quiz 283 | pmid=15043336 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15043336  }} </ref>
**[[thrombophlebitis]] of [[diploic veins]], which is facilitated by the fact that these vessels do not have valves, allowing for retrograde flow of [[bacteria]].
*[[Thrombophlebitis]] of [[diploic veins]], facilitated by the valveless nature of these vessels, allowing for retrograde flow of [[bacteria]]
**direct extension from [[osteomyelitis]] of the [[skull]].
*Direct extension from [[osteomyelitis]] of the [[skull]]
**following [[trauma]].
*[[Congenital defect]], such as communication between [[sinuses]] and areas of lesion
**following [[surgery]].
*[[Osteomyelitis]] of the [[skull]]  
**[[congenital defect]], such as communication between [[sinuses]] and areas of lesion.
*Extension of [[infection]] from [[otitis]] or [[mastoiditis]]
*Direct inoculation, during a [[surgical procedure]] or [[trauma]]
*Remote [[infection]] sites, through [[haematological]] spread, such as [[respiratory tract infection|respiratory]] and [[urinary tract infections]]


===Spinal Epidural Abscess===
===Spinal Epidural Abscess===
Unlike the ''virtual intracranial epidural space'', the ''spinal epidural space'' is a ''real space'', more specifically in the areas posterior and lateral to the [[spinal cord]], extending down the length of the [[spinal canal]]. This epidural space, which is larger at the sacral region, contains [[fat]], [[arteries]] and [[venous plexus]]. Because the [[dura mater]] is more adherent to the bony surface of the [[vertebral bodies]], from the ''[[foramen magnum]]'' down to the level of L1, the majority of spinal epidural abscesses are located posteriorly, extending to multiple levels.<ref name="pmid3589332">{{cite journal| author=Danner RL, Hartman BJ| title=Update on spinal epidural abscess: 35 cases and review of the literature. | journal=Rev Infect Dis | year= 1987 | volume= 9 | issue= 2 | pages= 265-74 | pmid=3589332 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=3589332  }} </ref><ref name="pmid1359381">{{cite journal| author=Darouiche RO, Hamill RJ, Greenberg SB, Weathers SW, Musher DM| title=Bacterial spinal epidural abscess. Review of 43 cases and literature survey. | journal=Medicine (Baltimore) | year= 1992 | volume= 71 | issue= 6 | pages= 369-85 | pmid=1359381 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=1359381  }} </ref><ref name="pmid10664371">{{cite journal| author=Akalan N, Ozgen T| title=Infection as a cause of spinal cord compression: a review of 36 spinal epidural abscess cases. | journal=Acta Neurochir (Wien) | year= 2000 | volume= 142 | issue= 1 | pages= 17-23 | pmid=10664371 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=10664371  }} </ref>
The majority of spinal epidural abscess cases occur as a result of spinal instrumentation, vascular access, and [[IV drug use]].<ref name="pmid24340840">{{cite journal| author=Strauss I, Carmi-Oren N, Hassner A, Shapiro M, Giladi M, Lidar Z| title=Spinal epidural abscess: in search of reasons for an increased incidence. | journal=Isr Med Assoc J | year= 2013 | volume= 15 | issue= 9 | pages= 493-6 | pmid=24340840 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=24340840  }} </ref> Unlike the virtual intracranial epidural space, the spinal epidural space is a real space; more specifically, the sequelae occurs in the areas posterior and lateral to the [[spinal cord]], extending down the length of the [[spinal canal]]. This epidural space, which is larger at the [[sacral]] region, contains [[fat]], [[arteries]] and [[venous plexus]]. Because the [[dura mater]] is more adherent to the bony surface of the [[vertebral bodies]], from the [[foramen magnum]] down to the level of L1, the majority of spinal epidural abscesses are located posteriorly, extending to multiple levels.<ref name="pmid3589332">{{cite journal| author=Danner RL, Hartman BJ| title=Update on spinal epidural abscess: 35 cases and review of the literature. | journal=Rev Infect Dis | year= 1987 | volume= 9 | issue= 2 | pages= 265-74 | pmid=3589332 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=3589332  }} </ref><ref name="pmid1359381">{{cite journal| author=Darouiche RO, Hamill RJ, Greenberg SB, Weathers SW, Musher DM| title=Bacterial spinal epidural abscess. Review of 43 cases and literature survey. | journal=Medicine (Baltimore) | year= 1992 | volume= 71 | issue= 6 | pages= 369-85 | pmid=1359381 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=1359381  }} </ref><ref name="pmid10664371">{{cite journal| author=Akalan N, Ozgen T| title=Infection as a cause of spinal cord compression: a review of 36 spinal epidural abscess cases. | journal=Acta Neurochir (Wien) | year= 2000 | volume= 142 | issue= 1 | pages= 17-23 | pmid=10664371 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=10664371  }} </ref>


With the progression of the inflammation, the spinal cord may be damaged in several ways:
Pathophysiological pathways for the progression of intracranial epidural abscess include:<ref name="Darouiche2006">{{cite journal|last1=Darouiche|first1=Rabih O.|title=Spinal Epidural Abscess|journal=New England Journal of Medicine|volume=355|issue=19|year=2006|pages=2012–2020|issn=0028-4793|doi=10.1056/NEJMra055111}}</ref>
*Thrombosis and thrombophlebitis of adjacent veins;
*Direct compression from the inflammatory mass;
*Ischemia;
*Bacterial toxins;
*Inflammatory response and its mediators.


[[Bacteria]] gain access to the [[epidural space]] by:
*[[neurosurgery|Neurosurgical]] procedures
*Hematogenous dissemination. ''Important to notice that, as the spinal [[epidural space]] might be infected by [[bacteria]] from elsewhere, so does [[bacteria]] infecting the spinal [[epidural space]],  might travel through the [[blood stream]] to [[infect]] other tissues.''
*[[Trauma]]
*Direct inoculation.
*[[Skin flora]] entering open wounds
This access is facilitated by several predisposing factors, such as:
**''[[Staphylococcus epidermidis]]''
*underlying disease ([[HIV]] [[infection]], [[alcoholism]] or [[diabetes]])
**''[[Escherichia coli]]''
*spinal condition (degenerative joint disease)
**''[[Pseudomonas aeruginosa]]''
*neurosurgical procedure
**''[[Haemophilus influenzae]]''
*local or systemic source of infection ([[osteomyelitis]], [[UTI]], soft-tissue [[infections]], IV drug use, [[sepsis]]).
**''[[Klebsiella pneumoniae]]''
As the [[inflammation]] progresses, the extension of the [[abscess]] also increases, to the average extent of 3 to 5 [[spinal cord]] segments. Nevertheless, certain situations, in which the whole [[spinal cord]] is involved may arise, in which case it's called ''panspinal infection''. <ref name="Darouiche2006">{{cite journal|last1=Darouiche|first1=Rabih O.|title=Spinal Epidural Abscess|journal=New England Journal of Medicine|volume=355|issue=19|year=2006|pages=2012–2020|issn=0028-4793|doi=10.1056/NEJMra055111}}</ref> However, the degree of damage, associated neurologic symptoms and sequelae, are not directly related to the extension of the [[abscess]], since even small [[abscesses]] may cause severe sequelae. Relating to the content of the [[abscess]] it may be essentially [[pus]], particularly in acute situations, or may be [[granulation tissue]] which is often times observed during the surgical drainage, especially in [[abscesses]] with more than 2 weeks.
**''[[Listeria monocytogenes]]''
 
As the [[inflammation]] progresses, the extension of the [[abscess]] also increases, on average by 3 to 5 [[spinal cord]] segments. However, the degree of damage, associated neurological symptoms, and sequelae are not directly related to the extension of the [[abscess]], as even small abscesses may cause severe [[sequelae]]. The [[abscess]] may contain [[pus]], often observed in acute cases, or [[granulation tissue]], often observed following the surgical intervention.


==References==
==References==
{{Reflist|2}}
{{Reflist|2}}


[[Category:Wikinfect]]
[[Category:Infectious disease]]
[[Category:Disease]]
[[Category:Disease]]
[[Category:Neurology]]
[[Category:Neurology]]
[[Category:Primary care]]

Latest revision as of 21:36, 29 July 2020

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: João André Alves Silva, M.D. [2]; Anthony Gallo, B.S. [3]

Overview

Epidural abscess pathophysiology differs based on the location of the infection and responsible organism. The majority of intracranial epidural abscess cases occur as a complication of cranial surgical procedures and sinusitis.[1] The majority of spinal epidural abscess cases occur as a result of spinal instrumentation, vascular access, and IV drug use.[2]

Pathophysiology

Epidural abscess pathophysiology differs based on the location of the infection and responsible organism.

Intracranial epidural abscess

Intracranial epidural abscess is the result of sequelae of cranial surgical procedures, sinusitis, and mastoiditis. Cranial dura mater is adherent to the inner table of the skull in the epidural space. This virtual space can become a real space by increasing pressure from a liquid, such as pus or blood, or a solid mass, such as a tumor. A tight adherence contributes to the slow progression and typical round-shape appearance of the abscess. Because the dura mater is tightly attached to the skull in the foramen magnum, intracranial epidural abscesses are usually restricted to the cranial cavity. On the periphery of the pus collection is a wall of inflammation, which may calcify and is identifiable in imaging studies.[1][3]

Pathophysiological pathways for the progression of intracranial epidural abscess include:[1]

Spinal Epidural Abscess

The majority of spinal epidural abscess cases occur as a result of spinal instrumentation, vascular access, and IV drug use.[2] Unlike the virtual intracranial epidural space, the spinal epidural space is a real space; more specifically, the sequelae occurs in the areas posterior and lateral to the spinal cord, extending down the length of the spinal canal. This epidural space, which is larger at the sacral region, contains fat, arteries and venous plexus. Because the dura mater is more adherent to the bony surface of the vertebral bodies, from the foramen magnum down to the level of L1, the majority of spinal epidural abscesses are located posteriorly, extending to multiple levels.[4][5][6]

Pathophysiological pathways for the progression of intracranial epidural abscess include:[7]

As the inflammation progresses, the extension of the abscess also increases, on average by 3 to 5 spinal cord segments. However, the degree of damage, associated neurological symptoms, and sequelae are not directly related to the extension of the abscess, as even small abscesses may cause severe sequelae. The abscess may contain pus, often observed in acute cases, or granulation tissue, often observed following the surgical intervention.

References

  1. 1.0 1.1 1.2 Fountas KN, Duwayri Y, Kapsalaki E, Dimopoulos VG, Johnston KW, Peppard SB; et al. (2004). "Epidural intracranial abscess as a complication of frontal sinusitis: case report and review of the literature". South Med J. 97 (3): 279–82, quiz 283. PMID 15043336.
  2. 2.0 2.1 Strauss I, Carmi-Oren N, Hassner A, Shapiro M, Giladi M, Lidar Z (2013). "Spinal epidural abscess: in search of reasons for an increased incidence". Isr Med Assoc J. 15 (9): 493–6. PMID 24340840.
  3. Heran NS, Steinbok P, Cochrane DD (2003). "Conservative neurosurgical management of intracranial epidural abscesses in children". Neurosurgery. 53 (4): 893–7, discussion 897-8. PMID 14519222.
  4. Danner RL, Hartman BJ (1987). "Update on spinal epidural abscess: 35 cases and review of the literature". Rev Infect Dis. 9 (2): 265–74. PMID 3589332.
  5. Darouiche RO, Hamill RJ, Greenberg SB, Weathers SW, Musher DM (1992). "Bacterial spinal epidural abscess. Review of 43 cases and literature survey". Medicine (Baltimore). 71 (6): 369–85. PMID 1359381.
  6. Akalan N, Ozgen T (2000). "Infection as a cause of spinal cord compression: a review of 36 spinal epidural abscess cases". Acta Neurochir (Wien). 142 (1): 17–23. PMID 10664371.
  7. Darouiche, Rabih O. (2006). "Spinal Epidural Abscess". New England Journal of Medicine. 355 (19): 2012–2020. doi:10.1056/NEJMra055111. ISSN 0028-4793.