Cysticercosis: Difference between revisions

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==Background==
==Background==
  [[File:pic cyst.png|thumbnail]]
  [[File:pic cyst.png|thumbnail]]
*Parasitic infection caused by larval stage of ''Taenia solium'' (pork tapeworm)<ref>CDC Cysticercosis http://www.cdc.gov/parasites/cysticercosis/</ref>
*[[Parasitic infection]] caused by larval stage of ''Taenia solium'' (pork tapeworm)<ref>CDC Cysticercosis http://www.cdc.gov/parasites/cysticercosis/</ref>
*Occurs when humans (definitive host) ingest poorly cooked pig (intermediate host) that is infected with larvae (cysticerci)
*Occurs when humans (definitive host) ingest poorly cooked pig (intermediate host) that is infected with larvae (cysticerci)
*Estimated 50-100 million people infected worldwide
*Estimated 50-100 million people infected worldwide
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**Subcutaneous tissue: nodules that are not cosmetically pleasing, but usually asymptomatic
**Subcutaneous tissue: nodules that are not cosmetically pleasing, but usually asymptomatic
**Muscle: asymptomatic or sometimes painful due to surrounding inflammation
**Muscle: asymptomatic or sometimes painful due to surrounding inflammation
**Cardiac cysts are rare: arrhythmias/conduction abnormalities
**Cardiac cysts are rare: [[arrhythmias]]/conduction abnormalities
*Neurocysticercosis (NCC)<ref>Wallin MT. et al. Neurocysticercosis in the United States: review of an important emerging infection. Neurology. Nov 9 2004;63(9):1559-64</ref>
*Neurocysticercosis (NCC)<ref>Wallin MT. et al. Neurocysticercosis in the United States: review of an important emerging infection. Neurology. Nov 9 2004;63(9):1559-64</ref>
**Parenchymal NCC  
**Parenchymal NCC  
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***Focal neurologic deficit
***Focal neurologic deficit
**Extraparenchymal NCC: more often present with headaches, vomiting, hydrocephalus
**Extraparenchymal NCC: more often present with headaches, vomiting, hydrocephalus
***Intraventricular cysts: can get lodged in ventricular outflow tracts and cause obstructive hydrocephalus and increased ICP causing nausea, vomiting, AMS, papilledema
***Intraventricular cysts: can get lodged in ventricular outflow tracts and cause obstructive hydrocephalus and [[increased ICP]] causing [[nausea]], [[vomiting]], [[AMS]], [[papilledema]]
***Subarachnoid cysts: can cause inflammatory response leading to arachnoiditis which may result in hydrocephalus, meningitis, stroke, and vasculitis
***Subarachnoid cysts: can cause inflammatory response leading to arachnoiditis which may result in hydrocephalus, [[meningitis]], [[stroke]], and vasculitis
***Ocular (1-3% of cases): diplopia if EOM involvement, vision loss or pain if intra-ocular
***Ocular (1-3% of cases): [[diplopia]] if EOM involvement, vision loss or pain if intra-ocular
***Spinal (1% of cases): radicular pain, paresthesias, cauda equina symptoms
***Spinal (1% of cases): radicular pain, paresthesias, [[cauda equina]] symptoms


==Differential Diagnosis==
==Differential Diagnosis==
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*Labs
*Labs
**Usually not helpful
**Usually not helpful
**Eosinophilia not seen unless cyst is leaking/ruptured
**[[Eosinophilia]] not seen unless cyst is leaking/ruptured
*Depending on presentation, involvement of the following services may be needed:
*Depending on presentation, involvement of the following services may be needed:
**Neurology: for seizures refractory to meds
**Neurology: for seizures refractory to meds
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*Home if asymptomatic or no complications w/ good pain control
*Home if asymptomatic or no complications w/ good pain control
*Admit if starting antihelminthic therapy for further testing as listed above and to monitor initial side effects of drug therapy
*Admit if starting antihelminthic therapy for further testing as listed above and to monitor initial side effects of drug therapy
*ICU for uncontrolled seizures, AMS, increased ICP  
*ICU for uncontrolled [[seizures]], [[AMS]], [[increased ICP]]


                                                                   
==See Also==
*[[Parasitic Diseases]]
*[[Travel Medicine]]


==Sources==
==Sources==
<references/>
<references/>

Revision as of 11:44, 1 September 2014

Background

Pic cyst.png
  • Parasitic infection caused by larval stage of Taenia solium (pork tapeworm)[1]
  • Occurs when humans (definitive host) ingest poorly cooked pig (intermediate host) that is infected with larvae (cysticerci)
  • Estimated 50-100 million people infected worldwide
    • 1,000 new cases in US per year, mostly in immigrants from Latin America but also seen in those from Asia or Africa
  • More than 80% of those affected are asymptomatic
  • Cysts can reside anywhere in body

Clinical Features

Divided into extraneural cysticercosis (outside CNS) and neurocysticercosis (which can be parenchymal, extraparenchymal or both)

  • Extraneural cysticercosis
    • Subcutaneous tissue: nodules that are not cosmetically pleasing, but usually asymptomatic
    • Muscle: asymptomatic or sometimes painful due to surrounding inflammation
    • Cardiac cysts are rare: arrhythmias/conduction abnormalities
  • Neurocysticercosis (NCC)[2]
    • Parenchymal NCC
      • Most common presentation of NCC
      • Most cases are asymptomatic and discovered incidentally after resolution of infection (see image below)
      • Those with symptoms usually present with seizures (focal or generalized)
      • Focal neurologic deficit
    • Extraparenchymal NCC: more often present with headaches, vomiting, hydrocephalus
      • Intraventricular cysts: can get lodged in ventricular outflow tracts and cause obstructive hydrocephalus and increased ICP causing nausea, vomiting, AMS, papilledema
      • Subarachnoid cysts: can cause inflammatory response leading to arachnoiditis which may result in hydrocephalus, meningitis, stroke, and vasculitis
      • Ocular (1-3% of cases): diplopia if EOM involvement, vision loss or pain if intra-ocular
      • Spinal (1% of cases): radicular pain, paresthesias, cauda equina symptoms

Differential Diagnosis

  • Brain abscess
  • Vasculitis
  • Tuberculomas or Mycotic granulomas
  • Primary brain tumors or metastases

Workup

  • Imaging is usually best
    • CT head (calcifications/edema); MRI (cysts +/- scolex, edema)[3]
    • X-rays or CT for extraneural cysticercosis
  • EITB assay for anticysticercal antibody
    • Serum (more sensitive) or CSF studies (less common)
  • Labs
    • Usually not helpful
    • Eosinophilia not seen unless cyst is leaking/ruptured
  • Depending on presentation, involvement of the following services may be needed:
    • Neurology: for seizures refractory to meds
    • Neurosurgery: hydrocephalus, mass effect, herniation
    • Infectious disease: if starting antiparasitic therapy
    • Ophthalmology: if suspect ocular involvement or if starting antibiotics and need to confirm no ocular involvement

Management

  • Asymptomatic: observation
  • Subcutaneous or intramuscular: typically observation
    • If just one lesion or cosmetic issue, surgical excision
    • Otherwise: NSAIDs

Symptomatic NCC

  • Anticonvulsants (keppra, dilantin, newer agents)
  • Antihelminthic therapy and steroids
    • Treat if edema, mass effect, or vasculitis
    • Don’t treat if old calcifications on CT without edema
    • Before starting these meds, need to check for:
      • positive PPD
      • co-infection w/ Strongyloides (steroids can cause to disseminate)
      • ocular involvement (inflammation associated with dying organisms can result in vision loss by causing chorioretinitis, retinal detachment, or vasculitis)
    • Pts started on therapy get admitted to watch for any adverse events initially

Antiparasite Medications

  • Albendazole
  • 15mg/kg/day divided in 2 doses[4]
    • First line therapy
  • Praziquantel
    • Second line therapy
    • 50-100mg/kg/day divided in 3 doses [5]
      • Steroids: Prednisone 1mg/kg/day or Dexamethasone 0.1mg/kg/day
    • If hydrocephalus present, CSF diversion with ventriculostomy or VP shunt by Neurosurgery and/or surgical resection of cysts.

Ocular

  • Intra-ocular: surgery [6]
  • Extra-ocular muscle involvement: albendazole and steroids[7]
  • Spinal intramedullary: possibly surgery

Disposition

  • Home if asymptomatic or no complications w/ good pain control
  • Admit if starting antihelminthic therapy for further testing as listed above and to monitor initial side effects of drug therapy
  • ICU for uncontrolled seizures, AMS, increased ICP

See Also

Sources

  1. ↑ CDC Cysticercosis http://www.cdc.gov/parasites/cysticercosis/
  2. ↑ Wallin MT. et al. Neurocysticercosis in the United States: review of an important emerging infection. Neurology. Nov 9 2004;63(9):1559-64
  3. ↑ García HH, Del Brutto OH. Imaging findings in neurocysticercosis. Acta Trop. 2003;87(1):71-8
  4. ↑ Garcia HH, Pretell EJ, Gilman RH, et al. A trial of antiparasitic treatment to reduce the rate of seizures due to cerebral cysticercosis. N Engl J Med. 2004;350(3):249-58.
  5. ↑ Sotelo J. et al. Albendazole vs praziquantel for therapy for neurocysticercosis. A controlled trial. Arch Neurol. May 1988;45(5):532-4
  6. ↑ Sharma T. et al. Intraocular cysticercosis: clinical characteristics and visual outcome after vitreoretinal surgery. Ophthalmology. 2003;110(5):996-1004
  7. ↑ Sundaram PM, Jayakumar N, Noronha V. Extraocular muscle cysticercosis - a clinical challenge to the ophthalmologists. Orbit. Dec 2004;23(4):255-62
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