Neurocysticercosis is the most common helminthic infection of the CNS but its diagnosis remains difficult. Clinical manifestations are nonspecific, most neuroimaging findings are not pathognomonic, and some serologic tests have low sensitivity and specificity. The authors provide diagnostic criteria for neurocysticercosis based on objective clinical, imaging, immunologic, and epidemiologic data. These include four categories of criteria stratified on the basis of their diagnostic strength, including the following: 1) absolute--histologic demonstration of the parasite from biopsy of a brain or spinal cord lesion, cystic lesions showing the scolex on CT or MRI, and direct visualization of subretinal parasites by funduscopic examination; 2) major--lesions highly suggestive of neurocysticercosis on neuroimaging studies, positive serum enzyme-linked immunoelectrotransfer blot for the detection of anticysticercal antibodies, resolution of intracranial cystic lesions after therapy with albendazole or praziquantel, and spontaneous resolution of small single enhancing lesions; 3) minor--lesions compatible with neurocysticercosis on neuroimaging studies, clinical manifestations suggestive of neurocysticercosis, positive CSF enzyme-linked immunosorbent assay for detection of anticysticercal antibodies or cysticercal antigens, and cysticercosis outside the CNS; and 4) epidemiologic--evidence of a household contact with Taenia solium infection, individuals coming from or living in an area where cysticercosis is endemic, and history of frequent travel to disease-endemic areas. Interpretation of these criteria permits two degrees of diagnostic certainty: 1) definitive diagnosis, in patients who have one absolute criterion or in those who have two major plus one minor and one epidemiologic criterion; and 2) probable diagnosis, in patients who have one major plus two minor criteria, in those who have one major plus one minor and one epidemiologic criterion, and in those who have three minor plus one epidemiologic criterion.

Proposed diagnostic criteria for neurocysticercosis

http://www.bio.umass.edu/micro/klingbeil/590s/Reading/Cysticer2003.pdf

Taenia solium cysticercosis

Emerging parasite zoonoses associated with water and food

Neurocysticercosis, the infection of the human brain by the larvae of Taenia solium, is a major cause of acquired epilepsy in most low-income countries. Cases of neurocysticercosis are becoming more common in high-income countries because of increased migration and travel. Diagnosis by neuroimaging and serological assessment has greatly improved over the past decade, and the natural progression of the disease and response to antiparasitic drugs is now much better understood. Neurocysticercosis is potentially eradicable, and control interventions are underway to eliminate this infection. Meanwhile, updated information on diagnosis and management of neurocysticercosis is required, especially for clinicians who are unfamiliar with its wide array of clinical presentations.

Neurocysticercosis: updated concepts about an old disease

Background and Methods. From June 1990 through July 1991, intracerebral infection with the larval stage of the pork tapeworm Taenia solium was diagnosed in four unrelated persons in an Orthodox Jewish community in New York City. None of the patients had eaten pork, and only one had traveled to a country in which T. solium infection was endemic. We investigated this outbreak, screened serum samples from family members and household contacts for antibodies to cysticercosis, and examined stool specimens from household employees for eggs of taenia species. Results. The four patients had recurrent seizures and brain lesions that were radiologically consistent with the presence of cysticerci. The diagnosis was confirmed in two patients by a brain biopsy, and in two by immunoblot assays for cysticercus antibodies. Of 17 immediate family members screened serologically, 7 from two families had cysticercus antibodies. Magnetic resonance imaging of the brain showed cystic lesions in two of the seropositive ...

https://www.nejm.org/doi/pdf/10.1056/NEJM199209033271004

Neurocysticercosis in an orthodox jewish community in New York City

An enzyme-linked immunoelectrotransfer blot (EITB) assay was developed for immunodiagnosing human cysticercosis. The assay uses lentil-lectin, affinity-purified glycoprotein antigens. A battery of 532 serum and 46 cerebrospinal fluid (CSF) samples (148 cases of parasitologically confirmed cysticercosis, 54 healthy controls, and 18 types of heterologous infections [376 cases]) were used to ascertain the assay's efficacy. All but three of the samples from cases of confirmed cysticercosis were positive; none of the samples from healthy controls or heterologous infections reacted to any of the diagnostic bands. Thus, the assay is 98% sensitive and 100% specific. We identified seven major glycoprotein bands that are commonly recognized by virtually all serum and/or CSF samples from patients with confirmed cysticercosis. There was no significant difference in test performance when CSF was compared with serum. The EITB assay is highly reproducible and simple to perform, and the reagents (including the antigens blotted onto strips) are very stable.

An Enzyme-Linked Immunoelectrotransfer Blot Assay and Glycoprotein Antigens for Diagnosing Human Cysticercosis (Taenia solium)

The present invention is directed to a method and a kit for diagnosing active human neurocysticercosis utilizing an immunoblot assay which comprises: detecting the presence of antibodies in the serum or cerebrospinal fluid of a human to be diagnosed, wherein the antibodies are reacted with Taenia solium larval antigens which have been isolated by lentil lectin affinity. The larval antigens are designated GP50, GP42, GP24, GP21, GP18, GP14, and GP13, wherein GP indicates that said antigen is a glycoprotein and the number indicates the molecular weight in K daltons, as determined by SDS-PAGE.

Joy A. Brand

Papers

An Enzyme-Linked Immunoelectrotransfer Blot Assay and Glycoprotein Antigens for Diagnosing Human Cysticercosis (Taenia solium)

Isolation of diagnostic glycoproteins to taenia solium, immunoblot-assay and method for the detection of human cysticercosis