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CompletedNCT00001912Updated Jul 2, 2017

Brain Tissue Swelling and Seizure Activity in Inactive Cysticercosis

An observational study in Cysticercosis, Cysts and Seizures, sponsored by National Institute of Allergy and Infectious Diseases (NIAID). Completed at 2 sites in 2 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2017-07-02.

Sponsored by National Institute of Allergy and Infectious Diseases (NIAID) · Observational

Study type
Observational
Enrollment
6
Ages
18 Years and older
Sex
All
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Study summary

This study will examine what causes seizures in patients with cysticercosis (pork tapeworm infection). A better understanding of this could lead to improved methods of controlling or preventing seizures.

In humans, the pork tapeworm (Taenia solium) lives in the small intestine. The parasite's microscopic eggs travel around the body-including to the brain-where they develop into cysts. Usually, the cysts don't cause symptoms until they die. Then, they provoke an inflammatory reaction that irritates the brain, causing seizures and other symptoms. The inflammation eventually goes away, but the dead cysts remain. Calcium deposits often form where the cysts are. Some of the calcified cysts develop swelling around them that seem to be associated with the development of seizures.

This study will explore how and why these dead, calcified cysts continue to cause seizures. In so doing, it will try to determine: 1) the best diagnostic imaging method for detecting swelling around the cysts; 2) how often swelling occurs; and 3) what makes some cysts prone to swelling and related seizure activity, while others are not.

Patients with cysticercosis who have had seizures or who have known or possible swelling around calcified cysts will be studied with various tests, including magnetic resonance imaging (MRI), computed tomography (CT) scans, electroencephalography (EEG), blood tests, and possibly lumbar puncture. Patients will be studied for two cycles of seizures (during active and quiet periods) or a maximum 4 years.

Read the detailed description

Seizures are the most common clinical manifestation of cerebral cysticercosis and occur in the presence of viable, dying, and calcified or non-calcified dead cysts. How calcified cysts provoke seizures is not known but recent observations demonstrated edema around some calcified lesions at the time of seizure activity and disappearance during periods when seizures were not occurring. Edema associated with foci in idiopathic epilepsy is highly unusual so that this observation suggests that the mechanism(s) associated with calcified cysts is unique. Documenting and understanding this phenomenon is important for a number of reasons. First, although by definition these lesions are inactive, e.g., not living larvae and do not require anti-parasitic treatment, they are frequently mistaken for active lesions and patients undergo unnecessary treatment. Second, a likely reason for perilesional edema is intermittent antigen release and subsequent host immune response resulting in inflammation and edema. If proved, then the treatment for this would not only involve suppression of seizure activity with anti-seizure medication but also the use of anti-inflammatory medications such as corticosteroids. The present protocol will systematically assess the presence of edema associated with calcified lesions at the time of seizure activity and attempt to determine why some calcified lesions in the same patient are foci of seizures while others are clinically silent. There are three related but separate questions. 1) What is the most sensitive MRI technique that can detect edema around calcified or inactive lesions? It is essential to determine the most sensitive methods initially because the use of insensitive techniques will lead to inaccurate assessments of which lesions are prone to lead to seizure activity and how many patients are affected. 2) How common is perilesional edema around calcified or inactive lesions associated with seizure activity? 3) What factors determine which lesions are prone to cause seizure activity? 4) Can perilesional edema be effectively treated or prevented? 5) Can perilesional edema be treated? We have reported from long term longitudinal studies in a handful of patients that only some of many lesions seem to be associated with seizure activity and edema.

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Conditions studied

  • Cysticercosis
  • Cysts
  • Seizures

Keywords

  • Cysticercosis
  • T. Solium
  • MRI
  • Seizures
  • Calcified Cysts
  • Taenia
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In context

Cysticercosis

10 studies on the registry are indexed under Cysticercosis; 2 are open to participants now.

Browse Cysticercosis studies →

Lead sponsor

National Institute of Allergy and Infectious Diseases (NIAID) is the lead sponsor of 2,446 studies on the registry; 179 are open to participants now.

Of its 405 completed or terminated interventional studies of FDA-regulated products, 302 (75%) have results posted.

Counted across the registry records on this site, refreshed daily.

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Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

18 years of age or older. If children are evaluated they can be seen under the general protocol and they may be entered into the present protocol under an exception.

Likely diagnosis of inactive cysticercosis and present or past seizure activity. Requires "a" and "b" plus any one of the remaining criteria:

  1. History of seizures or present seizure activity;
  2. Previously treated or has inactive disease and declines treatment;
  3. Single calcified lesions and positive serology;
  4. Multiple calcified lesions;
  5. Multiple small enhancing nodular lesions;
  6. History of cystic lesions responding to specific chemotherapy.

If female, not pregnant and using effective methods.

Exclusion criteria

EXCLUSION CRITERIA:

Less than 18 years of age.

Pregnant or unwilling to use effective measures.

Refuse blood tests.

Unwilling or unable to undergo testing according to the schedule.

Unable to undergo MRI or CT examinations.

Patients who require anesthesia to undergo imaging studies.

Terms in these criteria, in plain language(1)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

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Study design

Enrollment
6 participants (actual)
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Study locations

2 sites
  • National Institutes of Health Clinical Center, 9000 Rockville Pike
    Bethesda, Maryland 20892, United States
  • Universidad Peruana Cayetano Heredia
    Lima, Peru
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References and documents

Publications

  • White AC Jr. Neurocysticercosis: a major cause of neurological disease worldwide. Clin Infect Dis. 1997 Feb;24(2):101-13; quiz 114-5. doi: 10.1093/clinids/24.2.101. No abstract available. PubMed 9114131 ↗
  • Rajshekhar V, Chacko G, Haran RP, Chandy MJ, Chandi SM. Clinicoradiological and pathological correlations in patients with solitary cysticercus granuloma and epilepsy: focus on presence of the parasite and oedema formation. J Neurol Neurosurg Psychiatry. 1995 Sep;59(3):284-6. doi: 10.1136/jnnp.59.3.284. PubMed 7673957 ↗
  • Nash TE, Neva FA. Recent advances in the diagnosis and treatment of cerebral cysticercosis. N Engl J Med. 1984 Dec 6;311(23):1492-6. doi: 10.1056/NEJM198412063112307. No abstract available. PubMed 6390196 ↗
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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Jul 2, 2017, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT00001912
First posted
Nov 4, 1999
Start date
Aug 10, 1999
Completion
Apr 4, 2012
Last update
Jul 2, 2017

Study contacts

Henry Masur, M.D.
principal investigator · National Institutes of Health Clinical Center (CC)
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Apr 2012. You cannot join it, but the record below documents what was studied.

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