View source for Arachnoiditis

{{short description|Inflammation of the arachnoid mater}}
{{Infobox medical condition 
| name            = Arachnoiditis
| image           = ARACHNOIDITIS.JPG
| caption         = [[Myelogram]] showing arachnoiditis in the lumbar spine
|image2=Blausen 0044 Arachnoiditis.png
|caption2=Illustration of Arachnoiditis
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| field           = [[Neurosurgery]]
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'''Arachnoiditis''' is an [[Inflammation|inflammatory]] condition of the [[arachnoid mater]] or 'arachnoid', one of the membranes known as [[meninges]] that surround and protect the central nervous system. The outermost layer of the meninges is the [[dura mater]] (Latin for hard) and adheres to inner surface of the skull and vertebrae.<ref name="Neuroanatomy, Cranial Meninges">{{Citation |last1=Ghannam |first1=Jack Y. |title=Neuroanatomy, Cranial Meninges |date=2023 |url=http://www.ncbi.nlm.nih.gov/books/NBK539882/ |work=StatPearls |access-date=2023-11-04 |place=Treasure Island (FL) |publisher=StatPearls Publishing |pmid=30969704 |last2=Al Kharazi |first2=Khalid A.}}</ref> The arachnoid is under or "deep" to the dura and is a thin membrane that adheres directly to the surface of the brain and spinal cord.<ref name="Neuroanatomy, Cranial Meninges"/>

== Signs and symptoms ==
Arachnoid inflammation can lead to many painful and debilitating symptoms which can vary greatly in each case, and not all people experience all symptoms.<ref name="Peng-2023"/><ref name="Rice-2004a">{{Cite journal |last1=Rice |first1=I |last2=Wee |first2=M.Y.K. |last3=Thomson |first3=K |date=January 2004 |title=Obstetric epidurals and chronic adhesive arachnoiditis |journal=British Journal of Anaesthesia |volume=92 |issue=1 |pages=109–120 |doi=10.1093/bja/aeh009 |pmid=14665562 |issn=0007-0912|doi-access=free }}</ref><ref name="Rice-2004b">{{Cite journal |last1=Rice |first1=I |last2=Wee |first2=M.Y.K. |last3=Thomson |first3=K |date=January 2004 |title=Obstetric epidurals and chronic adhesive arachnoiditis |url=https://linkinghub.elsevier.com/retrieve/pii/S0007091217362372 |journal=British Journal of Anaesthesia |language=en |volume=92 |issue=1 |pages=109–120 |doi=10.1093/bja/aeh009|pmid=14665562 |doi-access=free }}</ref> Chronic pain is common, including [[neuralgia]], while [[numbness and tingling]] of the extremities can occur with spinal cord involvement, and bowel, bladder, and sexual functioning can be affected if the lower part of the spinal cord is involved.<ref name="Peng-2023" /><ref name="Rice-2004a" /><ref name="Rice-2004b" /> While arachnoiditis has no consistent pattern of symptoms, it frequently affects the nerves that supply the legs and lower back.<ref name="Peng-2023" /><ref name="Rice-2004a" /><ref name="Rice-2004b" /> Many patients experience difficulty sitting for long (or even short) periods of time due to discomfort or pain.<ref name="Rice-2004b" /><ref name="Peng-2023" />
== Etiology ==
Arachnoiditis has been described as having many different [[Etiology|etiologies]]. As an infectious source, tuberculosis,<ref name="Shah-2001">{{Cite journal |last1=Shah |first1=Jeshil |last2=Patkar |first2=Deepak |last3=Parmar |first3=Hemant |last4=Prasad |first4=Srinivasa |last5=Varma |first5=Ravi |date=2001-05-17 |title=Arachnoiditis associated with arachnoid cyst formation and cord tethering following myelography: Magnetic resonance features |url=https://onlinelibrary.wiley.com/doi/10.1046/j.1440-1673.2001.00911.x |journal=Australasian Radiology |language=en |volume=45 |issue=2 |pages=236–239 |doi=10.1046/j.1440-1673.2001.00911.x |pmid=11380373 |issn=0004-8461|url-access=subscription }}</ref><ref name="Safi-2021">{{Cite journal |last1=Safi |first1=Saleh |last2=Thabat |first2=Abdelnaser |last3=Arshad |first3=Mohamed |last4=Hanoun |first4=Mohamed |date=2021-09-01 |title=Arachnoiditis – A challenge in diagnosis and success in outcome – Case report |journal=Interdisciplinary Neurosurgery |volume=25 |pages=101219 |doi=10.1016/j.inat.2021.101219 |issn=2214-7519|doi-access=free }}</ref> syphilis,<ref name="Shah-2001" /><ref name="Safi-2021" /> candida,<ref name="Safi-2021" /> mycosis,<ref name="Safi-2021" /> and HIV.<ref name="Peng-2023"/> As a mechanical source, spinal and cranial surgery,<ref>{{Cite journal |last1=Werner |first1=Cassidy |last2=Mathkour |first2=Mansour |last3=Scullen |first3=Tyler |last4=Dallapiazza |first4=Robert F. |last5=Dumont |first5=Aaron S. |last6=Maulucci |first6=Christopher M. |date=July 2020 |title=Recurrent arachnoid cysts secondary to spinal adhesive arachnoiditis successfully treated with a ventriculoperitoneal shunt |url=https://linkinghub.elsevier.com/retrieve/pii/S0303846720301785 |journal=Clinical Neurology and Neurosurgery |language=en |volume=194 |pages=105835 |doi=10.1016/j.clineuro.2020.105835|pmid=32305826 |s2cid=215730361 |url-access=subscription }}</ref> trauma,<ref name="Wright-2003">{{Cite journal |last1=Wright |first1=Michael H. |last2=Denney |first2=Leann C. |date=May 2003 |title=A Comprehensive Review of Spinal Arachnoiditis |url=http://dx.doi.org/10.1097/00006416-200305000-00010 |journal=Orthopaedic Nursing |volume=22 |issue=3 |pages=215–219 |doi=10.1097/00006416-200305000-00010 |pmid=12803151 |issn=0744-6020|url-access=subscription }}</ref> and disc herniation.<ref name="Wright-2003" /> Prior disease including ankylosing spondylitis,<ref name="Shah-2001"/><ref>{{Cite journal |last1=Bilgen |first1=I. G. |last2=Yunten |first2=N. |last3=Ustun |first3=E. E. |last4=Oksel |first4=F. |last5=Gumusdis |first5=G. |date=1999-07-01 |title=Adhesive arachnoiditis causing cauda equina syndrome in ankylosing spondylitis: CT and MRI demonstration of dural calcification and a dorsal dural diverticulum |url=https://doi.org/10.1007/s002340050793 |journal=Neuroradiology |language=en |volume=41 |issue=7 |pages=508–511 |doi=10.1007/s002340050793 |pmid=10450845 |s2cid=44009176 |issn=1432-1920|url-access=subscription }}</ref> autoimmune vasculitis,<ref name="Peng-2023">{{Citation |last1=Peng |first1=Huanhuan |title=Arachnoiditis |date=2023 |url=http://www.ncbi.nlm.nih.gov/books/NBK555973/ |work=StatPearls |access-date=2023-11-08 |place=Treasure Island (FL) |publisher=StatPearls Publishing |pmid=32310433 |last2=Conermann |first2=Till}}</ref> and Guillain-Barré syndrome<ref name="Peng-2023"/> have been known to cause arachnoiditis. Chemical causes include morphine,<ref name="Davies 123–125">{{Cite journal |last=Davies |first=D. G. |date=January 1976 |title=Cerebrospinal fluid sampling technique and Astrup pH and PCO2 values |url=https://pubmed.ncbi.nlm.nih.gov/2575 |journal=Journal of Applied Physiology |volume=40 |issue=1 |pages=123–125 |doi=10.1152/jappl.1976.40.1.123 |issn=0021-8987 |pmid=2575}}</ref> myelograms with oil-based radiographic contrast agents,<ref name="Davies 123–125"/> phenolic solutions,<ref>{{Cite journal |last1=Jurga |first1=Szymon |last2=Szymańska-Adamcewicz |first2=Olga |last3=Wierzchołowski |first3=Wojciech |last4=Pilchowska-Ujma |first4=Emilia |last5=Urbaniak |first5=Łukasz |date=2021-02-01 |title=Spinal adhesive arachnoiditis: three case reports and review of literature |url=https://doi.org/10.1007/s13760-020-01431-1 |journal=Acta Neurologica Belgica |language=en |volume=121 |issue=1 |pages=47–53 |doi=10.1007/s13760-020-01431-1 |issn=2240-2993 |pmc=7937595 |pmid=32833147}}</ref> chlorhexidine,<ref>{{Cite journal |last1=Iqbal |first1=I. Mohamed |last2=Morris |first2=R. |last3=Hersch |first3=M. |date=November 2018 |title=Adhesive Arachnoiditis following Inadvertent Epidural Injection of 2% Chlorhexidine in 70% Alcohol—Partial Recovery over the Ensuing Eight Years |journal=Anaesthesia and Intensive Care |language=en |volume=46 |issue=6 |pages=572–574 |doi=10.1177/0310057X1804600606 |pmid=30447665 |issn=0310-057X|doi-access=free }}</ref> epidural injection of steroids and antibiotics,<ref name="Shah-2001"/> blood in subarachnoid hemorrhage,<ref>{{Cite journal |last1=Tachibana |first1=Toshiya |last2=Moriyama |first2=Tokuhide |last3=Maruo |first3=Keishi |last4=Inoue |first4=Shinichi |last5=Arizumi |first5=Fumihiro |last6=Yoshiya |first6=Shinichi |date=2014-11-01 |title=Subarachnoid-subarachnoid bypass for spinal adhesive arachnoiditis: Case report |url=https://thejns.org/spine/view/journals/j-neurosurg-spine/21/5/article-p817.xml |journal=Journal of Neurosurgery: Spine |language=en-US |volume=21 |issue=5 |pages=817–820 |doi=10.3171/2014.7.SPINE131082|pmid=25170651 |url-access=subscription }}</ref> epidural blood patches and anesthetics.<ref>{{Cite journal |last1=Tseng |first1=Sheng-Hong |last2=Lin |first2=Swei-Ming |date=1997-12-01 |title=Surgical treatment of thoracic arachnoiditis with multiple subarachnoid cysts caused by epidural anesthesia |url=https://www.sciencedirect.com/science/article/pii/S0303846797000863 |journal=Clinical Neurology and Neurosurgery |volume=99 |issue=4 |pages=256–258 |doi=10.1016/S0303-8467(97)00086-3 |pmid=9491300 |s2cid=45501339 |issn=0303-8467|url-access=subscription }}</ref><ref>{{Cite journal |last1=Carlswärd |first1=C. |last2=Darvish |first2=B. |last3=Tunelli |first3=J. |last4=Irestedt |first4=L. |date=August 2015 |title=Chronic adhesive arachnoiditis after repeat epidural blood patch |url=https://doi.org/10.1016/j.ijoa.2015.04.005 |journal=International Journal of Obstetric Anesthesia |volume=24 |issue=3 |pages=280–283 |doi=10.1016/j.ijoa.2015.04.005 |pmid=26119259 |issn=0959-289X|url-access=subscription }}</ref>

Oftentimes, the precise cause of arachnoiditis is not known due to the variable latency from cause to symptom onset. With growing incidence of spine surgery, a common cause of arachnoiditis is [[Neurosurgery|lumbar spine procedures]].<ref>{{Cite journal |last1=Gonzalez M. |first1=Claudia E. |last2=Enriquez |first2=Luis E. |last3=Cruz A. |first3=Camilo |date=2012-05-01 |title=Arachnoiditis Following Spinal Anesthesia for Cesarean Section |journal=Colombian Journal of Anesthesiology |volume=40 |issue=2 |pages=150–152 |doi=10.1016/S2256-2087(12)70031-7 |issn=2256-2087|doi-access=free }}</ref>
== Pathogenesis ==
The above etiologies can cause inflammation of the arachnoid, leading to arachnoiditis. This inflammation is enough to cause pain and even potentially neurological deficits - symptoms caused by nerves not communicating properly with the body's mechanisms for sensation and movement.<ref name="Rice-2004a"/><ref name="Killeen-2012">{{Cite journal |last1=Killeen |first1=T. |last2=Kamat |first2=A. |last3=Walsh |first3=D. |last4=Parker |first4=A. |last5=Aliashkevich |first5=A. |date=December 2012 |title=Severe adhesive arachnoiditis resulting in progressive paraplegia following obstetric spinal anaesthesia: a case report and review |journal=Anaesthesia |language=en |volume=67 |issue=12 |pages=1386–1394 |doi=10.1111/anae.12017 |pmid=23061983 |issn=0003-2409|doi-access=free }}</ref> The inflammation can lead to the formation of [[scar]] tissue and [[adhesion]] that can make the spinal nerves "stick" together, a condition where such tissue develops in and between the [[Meninges#Leptomeninges|leptomeninges]] - between dura and arachnoid or pia and arachnoid.<ref name="Killeen-2012" /> This condition can be very painful, especially when progressing to ''adhesive arachnoiditis''. ''Adhesive arachnoiditis'' occurs when inflammation leads to recruitment of cells to the area and fibrous exudate, and ensuing deposition of collagen forms bands that could cause ischemia or even atrophy of the spinal cord or nerve roots.<ref name="Killeen-2012" /><ref name="Stacey M 2018">{{Cite journal |last1=Cornelson |first1=Stacey M. |last2=Johnnie |first2=Edward D. |last3=Kettner |first3=Norman W. |date=2018-12-01 |title=Neural Mobilization in a 54-Year-Old Woman With Postoperative Spinal Adhesive Arachnoiditis |journal=Journal of Chiropractic Medicine |volume=17 |issue=4 |pages=283–288 |doi=10.1016/j.jcm.2018.07.004 |issn=1556-3707 |pmc=6391232 |pmid=30846922}}</ref> Chronic inflammation could lead to ''arachnoiditis ossificans'', in which the inflamed arachnoid becomes [[Ossification|ossified]], or turns to bone, and is thought to be a late-stage complication of the adhesive form of arachnoiditis.<ref>{{Cite journal |last1=Krätzig |first1=Theresa |last2=Dreimann |first2=Marc |last3=Mende |first3=Klaus Christian |last4=Königs |first4=Ingo |last5=Westphal |first5=Manfred |last6=Eicker |first6=Sven Oliver |date=2018-08-01 |title=Extensive Spinal Adhesive Arachnoiditis After Extradural Spinal Infection–Spinal Dura Mater Is No Barrier to Inflammation |url=https://www.sciencedirect.com/science/article/pii/S1878875018311732 |journal=World Neurosurgery |volume=116 |pages=e1194–e1203 |doi=10.1016/j.wneu.2018.05.219 |pmid=29883820 |s2cid=47002240 |issn=1878-8750|url-access=subscription }}</ref> More serious complications can occur, including spinal cord swelling, myelomalacia, cauda equina syndrome, and hydrocephalus.<ref name="Stacey M 2018"/><ref>{{Cite journal |last1=Morisako |first1=Hiroki |last2=Takami |first2=Toshihiro |last3=Yamagata |first3=Toru |last4=Chokyu |first4=Isao |last5=Tsuyuguchi |first5=Naohiro |last6=Ohata |first6=Kenji |date=2010 |title=Focal adhesive arachnoiditis of the spinal cord: Imaging diagnosis and surgical resolution |journal=Journal of Craniovertebral Junction and Spine |language=en |volume=1 |issue=2 |pages=100–106 |doi=10.4103/0974-8237.77673 |issn=0974-8237 |pmc=3075825 |pmid=21572630 |doi-access=free }}</ref>

==Diagnosis==
Diagnosis is based on a combination of clinical findings, patient examination, and imaging evaluation.<ref>{{Cite journal | vauthors = Kara T, Davulcu Ö, Ateş F, Arslan FZ, Sara HI, Akin A |date=2020-10-06 |title=What happened to cauda equina fibers? Adhesive arachnoiditis |url=http://apicareonline.com/index.php/APIC/article/view/1364 |journal=Anaesthesia, Pain & Intensive Care |volume=24 |issue=5 |doi=10.35975/apic.v24i5.1364 |s2cid=226319113 |issn=2220-5799|doi-access=free }}</ref> The most common affected area is the lumbar region of the back, and includes the classic symptomatic triad of back pain, neurological deficits, and MRI with notable adhesions.<ref>{{cite journal | vauthors = Parenti V, Huda F, Richardson PK, Brown D, Aulakh M, Taheri MR | title = Lumbar arachnoiditis: Does imaging associate with clinical features? | journal = Clinical Neurology and Neurosurgery | volume = 192 | pages = 105717 | date = May 2020 | pmid = 32062307 | doi = 10.1016/j.clineuro.2020.105717 | s2cid = 211019420 }}</ref> For the ossificans form of the condition, unenhanced [[computed tomography|CT]] may better show the presence and extent of arachnoid ossifications, and is complementary to [[magnetic resonance imaging|MRI]], as MRI can be less specific and findings can be confused with regions of [[calcification]] or [[hemosiderin]].<ref name="SteelAbrames2015">{{cite journal |vauthors=Steel CJ, Abrames EL, O'Brien WT |year=2015 |title=Arachnoiditis Ossificans - A Rare Cause of Progressive Myelopathy |journal=The Open Neuroimaging Journal |volume=9 |issue=1 |pages=13–20 |doi= 10.2174/1874440001509010013  |doi-access=free|pmc=4578143 |pmid=26401174}}</ref><ref name="MaulucciGhobrial2014">{{cite journal | vauthors = Maulucci CM, Ghobrial GM, Oppenlander ME, Flanders AE, Vaccaro AR, Harrop JS | title = Arachnoiditis ossificans: clinical series and review of the literature | journal = Clinical Neurology and Neurosurgery | volume = 124 | pages = 16–20 | date = September 2014 | pmid = 24999276 | doi = 10.1016/j.clineuro.2014.06.024 | s2cid = 12593117 }}</ref>

== Treatment ==
Arachnoiditis can be difficult to treat and treatment is generally limited to alleviation of pain and other symptoms.<ref name="ninds">{{cite web |title=Arachnoiditis Information Page |url=http://www.ninds.nih.gov/disorders/arachnoiditis/arachnoiditis.htm |archive-url=https://web.archive.org/web/20161209232820/http://www.ninds.nih.gov/disorders/arachnoiditis/arachnoiditis.htm |archivedate=2016-12-09 |access-date=2015-10-23 |work=[[National Institute of Neurological Disorders and Stroke]], [[National Institutes of Health]]}}</ref> While arachnoiditis may not yet be curable with the potential to be life-altering, management including medication, [[physical therapy]], and if appropriate, psychotherapy, can help patients cope with the difficulties it presents.<ref name="ninds" />

Medications that have been used to treat arachnoiditis include nonsteroidal anti-inflammatory drugs,<ref name=cegm>{{Cite journal | vauthors = Gonzalez CE, Enriquez LE, Cruz CA |date=May 2012 |title=Arachnoiditis Following Spinal Anesthesia for Cesarean Section |journal=Colombian Journal of Anesthesiology |language=en |volume=40 |issue=2 |pages=150–152 |doi=10.1016/S2256-2087(12)70031-7|doi-access=free }}</ref> pulse steroid therapy with methylprednisolone,<ref name=cegm/><ref name="Peng-2023"/><ref>{{cite journal | vauthors = Jurga S, Szymańska-Adamcewicz O, Wierzchołowski W, Pilchowska-Ujma E, Urbaniak Ł | title = Spinal adhesive arachnoiditis: three case reports and review of literature | journal = Acta Neurologica Belgica | volume = 121 | issue = 1 | pages = 47–53 | date = February 2021 | pmid = 32833147 | pmc = 7937595 | doi = 10.1007/s13760-020-01431-1 }}</ref> and multi-modal pain regimens.<ref name="Peng-2023"/> Surgical intervention generally has a poor outcome and may only provide temporary relief,<ref name="ninds" /> but some cases of surgical success have been reported.<ref name="TachibanaMoriyama2014">{{cite journal | vauthors = Tachibana T, Moriyama T, Maruo K, Inoue S, Arizumi F, Yoshiya S | title = Subarachnoid-subarachnoid bypass for spinal adhesive arachnoiditis | journal = Journal of Neurosurgery. Spine | volume = 21 | issue = 5 | pages = 817–820 | date = November 2014 | pmid = 25170651 | doi = 10.3171/2014.7.SPINE131082 }}</ref> Epidural steroid injections to treat sciatic pain have been linked as a ''cause'' of the disease by the U.S. [[Food and Drug Administration]] as well as in other research, and are therefore discouraged as a treatment for arachnoiditis as they will most likely worsen the condition.<ref name="nelson">{{cite journal |vauthors=Nelson DA, Landau WM |date=April 2001 |title=Intraspinal steroids: history, efficacy, accidentality, and controversy with review of United States Food and Drug Administration reports |journal=Journal of Neurology, Neurosurgery, and Psychiatry |volume=70 |issue=4 |pages=433–443 |doi=10.1136/jnnp.70.4.433 |pmc=1737322 |pmid=11254764 |doi-access=free}}</ref><ref name="shaw">{{cite journal |vauthors=Shaw MD, Russell JA, Grossart KW |date=February 1978 |title=The changing pattern of spinal arachnoiditis |journal=Journal of Neurology, Neurosurgery, and Psychiatry |volume=41 |issue=2 |pages=97–107 |doi=10.1136/jnnp.41.2.97 |pmc=492975 |pmid=632824}}</ref><ref name="NealKopp2015">{{cite journal | vauthors = Neal JM, Kopp SL, Pasternak JJ, Lanier WL, Rathmell JP | title = Anatomy and Pathophysiology of Spinal Cord Injury Associated With Regional Anesthesia and Pain Medicine: 2015 Update | journal = Regional Anesthesia and Pain Medicine | volume = 40 | issue = 5 | pages = 506–525 | year = 2015 | pmid = 26263076 | doi = 10.1097/AAP.0000000000000297 | s2cid = 10759432 | url = https://zenodo.org/record/890018 }}</ref>

==Prognosis==
Arachnoiditis is a chronic disorder with no known cure,<ref name="ninds" /> and prognosis may be difficult to determine because of an unclear correlation between the beginning of the disease or source and the appearance of symptoms. For many, arachnoiditis is a disabling disease that causes chronic pain and neurological deficits,<ref name="SteelAbrames2015" /> and may also lead to other spinal cord conditions, such as [[syringomyelia]].<ref name="Brammah">{{cite journal | vauthors = Brammah TB, Jayson MI | title = Syringomyelia as a complication of spinal arachnoiditis | journal = Spine | volume = 19 | issue = 22 | pages = 2603–2605 | date = November 1994 | pmid = 7855688 | doi = 10.1097/00007632-199411001-00019 | s2cid = 34679325 | doi-access = free }}</ref><ref name="IbrahimKamali-Nejad2010">{{cite journal | vauthors = Ibrahim GM, Kamali-Nejad T, Fehlings MG | title = Arachnoiditis ossificans associated with syringomyelia: An unusual cause of myelopathy | journal = Evidence-Based Spine-Care Journal | volume = 1 | issue = 2 | pages = 46–51 | date = August 2010 | pmid = 23637667 | pmc = 3623106 | doi = 10.1055/s-0028-1100914 }}</ref>

== References ==
{{Reflist}}

== Further reading ==
{{refbegin}}
* {{cite journal | vauthors = Duke RJ, Hashimoto SA | title = Familial spinal arachnoiditis. A new entity | journal = Archives of Neurology | volume = 30 | issue = 4 | pages = 300–303 | date = April 1974 | pmid = 4816834 | doi = 10.1001/archneur.1974.00490340028005 }}
{{refend}}

== External links ==
{{Medical resources
|   DiseasesDB     = 22543
|   ICD10          = {{ICD10|G|03|9|g|00}}
|   ICD9           = {{ICD9|320}}-{{ICD9|322}}
|   ICDO           =
|   OMIM           =
|   MedlinePlus    =
|   eMedicineSubj  = radio
|   eMedicineTopic = 49
|   MeshID         = D001100
}}
* {{NINDS|arachnoiditis|Arachnoiditis Information Page }}
* {{RareDiseases|5839|Arachnoiditis; Familial spinal arachnoiditis (subtype); Spinal tuberculous arachnoiditis (subtype)}}
* {{OMIM|182950|Spinal arachnoiditis}}

[[Category:Inflammatory diseases of the central nervous system]]