Disease caused by cyst stage of infestation by tapeworm Echinococcus species
Liver, lung involvement most common
Bone (0.5-4%) → spine involved in 50% of cases
Multiple echinococcal species produce disease; complex life cycle
Echinococcus granulosus: Causative agent of hydatid disease in man/other mammals
Dog is definite host; parasitized by adult tapeworm
Gravid proglottids shed by tapeworm, disintegrate in dog intestine
Eggs passed in feces
Mammals act as intermediate host after ingestion of eggs (typically sheep, cattle)
Eggs hatch in intestine, penetrate gut wall, travel via lymphatic/blood vessels throughout body
Cyst develops into infective protoscolices in 1-2 years
Dogs then ingest protoscolices on death of intermediate host (predation/scavenging)
Cyst wall digested in gut, allowing development of adult worms
E. multilocularis: Causative agent of alveolar hydatid disease in man/other mammals
Fox is most important definitive host
Cyst grows invasively by external budding, diffuse growth through infected organ
Presents as ramifying, porous, necrotic mass
E. vogeli: Polycystic form in Central and South America
Bush dog is definitive host
IMAGING
General Features
Radiographic Findings
CT Findings
MR Findings
Nonvascular Interventions
Imaging Recommendations
DIFFERENTIAL DIAGNOSIS
PATHOLOGY
General Features
Staging, Grading, & Classification
Gross Pathologic & Surgical Features
Microscopic Features
CLINICAL ISSUES
Presentation
Demographics
Natural History & Prognosis
Treatment
DIAGNOSTIC CHECKLIST
Consider
Image Interpretation Pearls
Selected References
Saul D et al: Of Cestodes and men: surgical treatment of a spinal hydatid cyst. J Neurol Surg A Cent Eur Neurosurg. 81(1):86-90, 2020
Padayachy LC et al: Hydatid disease (Echinococcus) of the central nervous system. Childs Nerv Syst. 34(10):1967-71, 2018
Agnihotri M et al: Hydatid disease of the spine: a rare case. J Craniovertebr Junction Spine. 8(2):159-60, 2017
Neumayr A et al: Spinal cystic echinococcosis--a systematic analysis and review of the literature: part 1. Epidemiology and anatomy. PLoS Negl Trop Dis. 7(9):e2450, 2013
Neumayr A et al: Spinal cystic echinococcosis--a systematic analysis and review of the literature: part 2. Treatment, follow-up and outcome. PLoS Negl Trop Dis. 7(9):e2458, 2013
Thaler M et al: Severe kyphoscoliosis after primary Echinococcus granulosus infection of the spine. Eur Spine J. 19(9):1415-22, 2010
Doganay S et al: Role of conventional and diffusion-weighted magnetic resonance imaging of spinal treatment protocol for hydatid disease. J Spinal Cord Med. 32(5):574-7, 2009
Güneçs M et al: Multiple intradural spinal hydatid disease: a case report and review of literature. Spine (Phila Pa 1976). 34(9):E346-50, 2009
Lakhdar F et al: Spinal intradural extramedullary hydatidosis: report of three cases. Neurosurgery. 65(2):372-6; discussion 376-7, 2009
Sasani M et al: Spontaneous drainage of an asymptomatic recurrent hydatid cyst of the sacrum. Spine (Phila Pa 1976). 34(7):E269-71, 2009
Viljoen H et al: Hydatid disease of the spine. Spine (Phila Pa 1976). 33(22):2479-80, 2008
El-Arousy MH et al: Cerebrospinal echinococcosis: serodiagnosis using different hydatid cyst fluid antigens. J Egypt Soc Parasitol. 35(1):193-204, 2005
El Kohen A et al: Multiple hydatid cysts of the neck, the nasopharynx and the skull base revealing cervical vertebral hydatid disease. Int J Pediatr Otorhinolaryngol. 67(6):655-62, 2003
Hadjipavlou AG et al: Effectiveness and pitfalls of percutaneous transpedicle biopsy of the spine. Clin Orthop. (411):54-60, 2003
Karadereler S et al: Primary spinal extradural hydatid cyst in a child: case report and review of the literature. Eur Spine J. 11(5):500-3, 2002
Hassan FO et al: Primary pelvic hydatid cyst: an unusual cause of sciatica and foot drop. Spine. 26(2):230-2, 2001
Stabler A et al: Imaging of spinal infection. Radiol Clin North Am. 39(1):115-35, 2001
Bruschi F et al: Immunochemical and molecular characterization of vertebral hydatid fluid. Scand J Infect Dis. 31(3):322-3, 1999
Savas R et al: Spinal cord compression due to costal Echinococcus multilocularis. Comput Med Imaging Graph. 23(2):85-8, 1999
Mazyad MA et al: Spinal cord hydatid cysts in Egypt. J Egypt Soc Parasitol. 28(3):655-8, 1998
Normelli HC et al: Vertebral hydatid cyst infection (Echinococcus granulosus): a case report. Eur Spine J. 7(2):158-61, 1998
von Sinner WN et al: Case report 833: Primary spinal echinococcosis (Echinococcus granulosus) of lumbosacral spine with destruction of the left pedicles of L3-5 and extension of a large paraspinal cystic mass into the spinal canal. Skeletal Radiol. 23(3):220-3, 1994
Sharif HS: Role of MR imaging in the management of spinal infections. AJR Am J Roentgenol. 158(6):1333-45, 1992
Dernevik L et al: Management of dumbbell tumours. Reports of seven cases. Scand J Thorac Cardiovasc Surg. 24(1):47-51, 1990
Richards KS et al: Effect of albendazole on human hydatid cysts: an ultrastructural study. HPB Surg. 2(2):105-12; discussion 112-3, 1990
Charles RW et al: Echinococcal infection of the spine with neural involvement. Spine. 13(1):47-9, 1988
Bhargava S: Radiology--including computed tomography--of parasitic diseases of the central nervous system. Neurosurg Rev. 6(3):129-37, 1983
Braithwaite PA et al: Vertebral hydatid disease: radiological assessment. Radiology. 140(3):763-6, 1981
Kaufman DM et al: Infectious agents in spinal epidural abscesses. Neurology. 30(8):844-50, 1980
Karvounis PC et al: Intradural spinal echinococcus simulating lumbar disc protrusion. Neurochirurgia (Stuttg). 20(2):58-60, 1977
Disease caused by cyst stage of infestation by tapeworm Echinococcus species
Liver, lung involvement most common
Bone (0.5-4%) → spine involved in 50% of cases
Multiple echinococcal species produce disease; complex life cycle
Echinococcus granulosus: Causative agent of hydatid disease in man/other mammals
Dog is definite host; parasitized by adult tapeworm
Gravid proglottids shed by tapeworm, disintegrate in dog intestine
Eggs passed in feces
Mammals act as intermediate host after ingestion of eggs (typically sheep, cattle)
Eggs hatch in intestine, penetrate gut wall, travel via lymphatic/blood vessels throughout body
Cyst develops into infective protoscolices in 1-2 years
Dogs then ingest protoscolices on death of intermediate host (predation/scavenging)
Cyst wall digested in gut, allowing development of adult worms
E. multilocularis: Causative agent of alveolar hydatid disease in man/other mammals
Fox is most important definitive host
Cyst grows invasively by external budding, diffuse growth through infected organ
Presents as ramifying, porous, necrotic mass
E. vogeli: Polycystic form in Central and South America
Bush dog is definitive host
IMAGING
General Features
Radiographic Findings
CT Findings
MR Findings
Nonvascular Interventions
Imaging Recommendations
DIFFERENTIAL DIAGNOSIS
PATHOLOGY
General Features
Staging, Grading, & Classification
Gross Pathologic & Surgical Features
Microscopic Features
CLINICAL ISSUES
Presentation
Demographics
Natural History & Prognosis
Treatment
DIAGNOSTIC CHECKLIST
Consider
Image Interpretation Pearls
Selected References
Saul D et al: Of Cestodes and men: surgical treatment of a spinal hydatid cyst. J Neurol Surg A Cent Eur Neurosurg. 81(1):86-90, 2020
Padayachy LC et al: Hydatid disease (Echinococcus) of the central nervous system. Childs Nerv Syst. 34(10):1967-71, 2018
Agnihotri M et al: Hydatid disease of the spine: a rare case. J Craniovertebr Junction Spine. 8(2):159-60, 2017
Neumayr A et al: Spinal cystic echinococcosis--a systematic analysis and review of the literature: part 1. Epidemiology and anatomy. PLoS Negl Trop Dis. 7(9):e2450, 2013
Neumayr A et al: Spinal cystic echinococcosis--a systematic analysis and review of the literature: part 2. Treatment, follow-up and outcome. PLoS Negl Trop Dis. 7(9):e2458, 2013
Thaler M et al: Severe kyphoscoliosis after primary Echinococcus granulosus infection of the spine. Eur Spine J. 19(9):1415-22, 2010
Doganay S et al: Role of conventional and diffusion-weighted magnetic resonance imaging of spinal treatment protocol for hydatid disease. J Spinal Cord Med. 32(5):574-7, 2009
Güneçs M et al: Multiple intradural spinal hydatid disease: a case report and review of literature. Spine (Phila Pa 1976). 34(9):E346-50, 2009
Lakhdar F et al: Spinal intradural extramedullary hydatidosis: report of three cases. Neurosurgery. 65(2):372-6; discussion 376-7, 2009
Sasani M et al: Spontaneous drainage of an asymptomatic recurrent hydatid cyst of the sacrum. Spine (Phila Pa 1976). 34(7):E269-71, 2009
Viljoen H et al: Hydatid disease of the spine. Spine (Phila Pa 1976). 33(22):2479-80, 2008
El-Arousy MH et al: Cerebrospinal echinococcosis: serodiagnosis using different hydatid cyst fluid antigens. J Egypt Soc Parasitol. 35(1):193-204, 2005
El Kohen A et al: Multiple hydatid cysts of the neck, the nasopharynx and the skull base revealing cervical vertebral hydatid disease. Int J Pediatr Otorhinolaryngol. 67(6):655-62, 2003
Hadjipavlou AG et al: Effectiveness and pitfalls of percutaneous transpedicle biopsy of the spine. Clin Orthop. (411):54-60, 2003
Karadereler S et al: Primary spinal extradural hydatid cyst in a child: case report and review of the literature. Eur Spine J. 11(5):500-3, 2002
Hassan FO et al: Primary pelvic hydatid cyst: an unusual cause of sciatica and foot drop. Spine. 26(2):230-2, 2001
Stabler A et al: Imaging of spinal infection. Radiol Clin North Am. 39(1):115-35, 2001
Bruschi F et al: Immunochemical and molecular characterization of vertebral hydatid fluid. Scand J Infect Dis. 31(3):322-3, 1999
Savas R et al: Spinal cord compression due to costal Echinococcus multilocularis. Comput Med Imaging Graph. 23(2):85-8, 1999
Mazyad MA et al: Spinal cord hydatid cysts in Egypt. J Egypt Soc Parasitol. 28(3):655-8, 1998
Normelli HC et al: Vertebral hydatid cyst infection (Echinococcus granulosus): a case report. Eur Spine J. 7(2):158-61, 1998
von Sinner WN et al: Case report 833: Primary spinal echinococcosis (Echinococcus granulosus) of lumbosacral spine with destruction of the left pedicles of L3-5 and extension of a large paraspinal cystic mass into the spinal canal. Skeletal Radiol. 23(3):220-3, 1994
Sharif HS: Role of MR imaging in the management of spinal infections. AJR Am J Roentgenol. 158(6):1333-45, 1992
Dernevik L et al: Management of dumbbell tumours. Reports of seven cases. Scand J Thorac Cardiovasc Surg. 24(1):47-51, 1990
Richards KS et al: Effect of albendazole on human hydatid cysts: an ultrastructural study. HPB Surg. 2(2):105-12; discussion 112-3, 1990
Charles RW et al: Echinococcal infection of the spine with neural involvement. Spine. 13(1):47-9, 1988
Bhargava S: Radiology--including computed tomography--of parasitic diseases of the central nervous system. Neurosurg Rev. 6(3):129-37, 1983
Braithwaite PA et al: Vertebral hydatid disease: radiological assessment. Radiology. 140(3):763-6, 1981
Kaufman DM et al: Infectious agents in spinal epidural abscesses. Neurology. 30(8):844-50, 1980
Karvounis PC et al: Intradural spinal echinococcus simulating lumbar disc protrusion. Neurochirurgia (Stuttg). 20(2):58-60, 1977
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