Detection of HP10 antigen in serum for diagnosis and follow-up of subarachnoidal and intraventricular human neurocysticercosis

Abstract

Introduction: Neurocysticercosis (NC), a parasitic disease caused by Taenia solium, may be either asymptomatic or show a mild to severe clinical picture with intracranial hypertension. The most severe form of the disease is caused when viable cysticerci are localised in the ventricles or in subarachnoidal cisterns at the base of the skull. Detection of the secreted metacestode antigen HP10 in cerebrospinal fluid is a sensitive and specific method for the diagnosis of these severe NC cases. Objective and methods: To evaluate the validity of HP10 antigen detection ELISA when applied to serum, using paired serum and cerebrospinal fluid samples from 116 radiologically and clinically characterised NC patients. Results: The HP10 antigen assay exhibited a similarly high sensitivity in identifying severe NC cases from sera (84.8%) and CSF (91.3%). In contrast, HP10 antigen was rarely detected in asymptomatic or mild NC cases (3 of 57). Importantly, the HP10 antigen assay applied to serum showed high specificity (94%) when used in 126 serum samples of non-NC subjects from an endemic community with a confirmed coproparasitological diagnosis of intestinal parasitic infections. Finally, the HP10 assay also proved to be of value in the follow-up of treated patients. Conclusion: This study confirms that detection of the metacestode HP10 antigen in serum is a useful tool for diagnosis and follow-up of patients with severe forms of NC treated with cysticidal drugs.

Successful Antiparasitic Treatment for Cysticercosis is Associated with a Fast and Marked Reduction of Circulating Antigen Levels in a Naturally Infected Pig Model

“…[21][22][23] Antigen-ELISA has been widely used to detect cysticercosis in humans as well as in pigs. 14,15,[24][25][26][27] Using serial posttreatment serum circulating antigen levels in pigs, we assessed whether the changes in circulating antigen levels correlate with the response to antiparasitic treatment, and whether antigen levels at the time of necropsy correlate with the final infection burden.…”

Clinical Diagnoses of Neurocysticercosis

“…ELISA test for antibodies or antigen detection have showed higher sensitivities and specificities in CSF than in sera [31]. EITB sensibility seems to be not significantly different in sera and CSF while specificity is higher in CSF [32].…”

“…These diagnostic criteria may be useful to identify patients with mainly parenchymal forms of NC, but it is not for patients with extraparenchymal forms of NCC [31]. Among minor criteria are considered "manifestations suggestive of neurocysticercosis" which include seizures, focal neurologic deficits, increased intracranial pressure, and intellectual deterioration, which are predominantly related to parenchymal location of lesions, but not necessarily to extraparenchymal clinical manifestations such us those associated with intraventricular cysts or NCC meningeal inflammation.…”

“…It is very hard to accept that such a patient may unquestionably have cysticerci in the brain. Some authors have claimed that the generalized use of Del Brutto et al [38 ] criteria have created some distortion in the present perception of NCC [31] A broad consensus now exists that these criteria should be revised to incorporate current scientific knowledge, in order to achieve a new consensus on the diagnosis of NCC.…”

“…In patients with reliable diagnosis of NCC by imaging studies, immunological test is not required, since a negative test will not discard a NCC. When imaging of extraparnechymal cysts is doubtful, determination of antigens by ELISA in CSF may be helpful [31].…”