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Background Neurocysticercosis is a major cause of acquired epilepsy. Larval cysts in the human brain eventually resolve and either disappear or leave a calcification that is associated with seizures. In this study, we assessed the proportion of calcification in parenchymal neurocysticercosis and risk factors associated with calcification. Methods Data for 220 patients with parenchymal NCC from 3 trials of antiparasitic treatment were assessed to determine what proportion of the cysts that resolved 6 months after treatment ended up in a residual calcification at 1 year. Also, we evaluated the risk factors associated with calcification. Results The overall proportion of calcification was 38% (188/497 cysts, from 147 patients). Predictors for calcification at the cyst level were cysts larger than 14 mm (risk ratio [RR], 1.34; 95% confidence interval [CI], 1.02–1.75) and cysts with edema at baseline (RR, 1.39; 95% CI, 1.05–1.85). At the patient level, having had more than 24 months with seizures (RR, 1.25; 95% CI, 1.08–1.46), mild antibody response (RR, 1.14; 95% CI, 1.002–1.27), increased dose albendazole regime (RR, 1.26; 95% CI, 1.14–1.39), lower doses of dexamethasone (RR, 1.36; 95% CI, 1.02–1.81), not receiving early antiparasitic retreatment (RR, 1.45; 95% CI, 1.08–1.93), or complete cure (RR, 1.48; 95% CI, 1.29–1.71) were associated with a increased risk of calcification. Conclusions Approximately 38% of parenchymal cysts calcify after antiparasitic treatment. Some factors associated with calcification are modifiable and may be considered to decrease or avoid calcification, potentially decreasing the risk for seizure relapses.

Background. Neurocysticercosis (NCC) is a frequent cause of epilepsy worldwide. Compared with the more common parenchymal brain cysts, extraparenchymal infections are difficult to manage and have a poor prognosis. Serological assays are used to detect circulating Taenia solium antigens or anti-T. solium antibodies in serum or cerebrospinal fluid (CSF) samples. There are no guidelines on whether to use serum or CSF specimens for a particular assay. Methods. We obtained paired serum and CSF samples from 91 patients with NCC (48 had intraparenchymal NCC, and 43 had extraparenchymal NCC) for detection of antibodies, using an enzyme-linked immunotransfer blot (EITB) assay, and antigens, using a monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA). Results. For the intraparenchymal NCC group, the EITB assay yielded more true-positive results for serum samples, and the ELISA yielded slightly more true-positive results for CSF samples than for serum samples, but none of these differences were statistically significant. Most patients with calcified NCC were antibody positive but antigen negative. For extraparenchymal disease, all samples were antibody positive, and all but 2 were antigen positive, with most samples containing high antigen levels. Conclusions. The sensitivity of antibody-detecting EITB assays is not increased through the use of CSF samples rather than serum samples. The antigen-detecting ELISA performed better for CSF samples than for serum samples, but for both specimen types it was less sensitive than the EITB assay. Active and inactive NCC are better differentiated from each other by the antigen-detecting ELISA, for both serum and CSF samples. High antigen levels suggest the presence of subarachnoid NCC.

Neurocysticercosis (NCC) is a major cause of neurological morbidity in the developing world. This study aimed to assess the treatment costs and productivity losses associated with NCC in Peru. NCC patients were identified through retrospective chart analysis. Patients meeting inclusion criteria were interviewed in order to obtain data on symptom history, treatment costs, productivity losses and health service utilisation patterns. These data were modelled to determine average treatment costs and productivity losses over 2 years. Our findings show that treatment costs and productivity losses consume 54% of an annual minimum wage salary during the first year of treatment and 16% during the second year. Diagnosis (36%) and drug therapy (27%) represent the most expensive healthcare-related costs. These costs are prohibitive for some-8% of our study sample had no diagnostic tests during their first 6 months of disease, and two-thirds of those who delayed treatment reportedly did so due to their inability to pay. Two-thirds of wage-earners lost their jobs owing to NCC and only 61% were able to re-engage in wage-earning activities. This study highlights the need to expand financial coverage to ensure the poor have access to health services and do not become further impoverished.

Twenty-five patients with calcified neurocysticercosis (two to four intraparenchymal brain calcifications) were asked to have a non-contrasted computed tomography (CT) scan of the thighs to determine the frequency of muscle calcifications detected by this technique. Thirteen (52%) showed one or more muscle calcifications. The numbers of calcifications in the thighs and the brain were not correlated. Patients with a positive CT scan for muscle calcifications were also examined by X-rays to compare both methods. Only 6 of 13 had visible calcifications on X-ray. Thigh CT scans can demonstrate muscle calcifications in a significant proportion of patients with calcified neurocysticercosis.

T aenia solium , the pork tapeworm, is endemic in most developing countries. The adult tapeworm only lives in the small intestine of humans, who get infected eating poorly cooked pork with cystic larvae. Tapeworm carriers expel microscopic tapeworm eggs and occasionally tapeworm segments with the stools. In areas with poor sanitation, pigs ingest stools from the environment and become infected with larvae.1 Humans can also get infected with cysticercosis by fecal‐oral contamination, clustering around the houses where a tapeworm carrier lives. In this issue, O’Neal and colleagues report two cases of neurocysticercosis in a family of refugees from Burma who moved to a refugee camp in Thailand and then to the United States.2 In this report, the occurrence of multiple cases in a family demonstrates the focal nature of cysticercosis transmission, suggesting that the detection of a confirmed cysticercosis case should prompt the evaluation of other household members for both symptomatic cysticercosis and intestinal taeniasis. It also adds to reports from other countries published in the journal and elsewhere (including a case report in an immigrant from Laos 3 and a series of neurocysticercosis cases in Israeli travelers 4 ), reflecting the wide areas of endemicity of the disease.2–8 Despite many advances in the diagnosis of cysticercosis in the past two decades, the primary diagnosis is still obtained by neuroimaging [either computed tomography (CT) or magnetic resonance imaging (MRI)], poorly available and economically difficult to obtain in rural endemic areas (or immigrant camps). The requirement for imaging arises from the need to know … Corresponding Author: Hector H. Garcia, MD, PhD, Instituto Nacional de Ciencias Neurologicas, Transmissible Diseases, Lima, Peru. E‐mail: hgarcia{at}jhsph.edu

In cases of cysticercosis, seizures and other symptoms occur in persons with only calcified brain lesions. The presence of perilesional edema has been documented in association with calcified lesions in symptomatic patients, but the frequency of this complication and characteristics of the patients who develop it are not known. Patients in Peru and the United States with neurocysticercosis, documented by positive results of serological testing and with only calcified lesions as shown using computerized tomography, were studied using magnetic resonance imaging. Perilesional edema was observed in slightly more than one-third of the patients, and some patients had frequent, severely disabling episodes. Those with an increased proportion of enhancing calcified lesions were more likely to show perilesional edema. Edema around calcified lesions is common in this population and is associated with seizures and neurological morbidity.

The efficacy of albendazole (ABZ) treatment for human neurocysticercosis (NCC) was assessed by using a monoclonal antibody-based parasite antigen detection ELISA which specifically detects the products of living cysticerci in human serum. The assay displayed 85% diagnostic sensitivity, detecting 39 of 46 NCC cases. Only patients with a single viable cyst or only enhancing lesions (degenerating parasites) were seronegative. Specificity of the assay was 92% (23/25) when tested in healthy Peruvian volunteers. In 'cured' patients, in whom all parasites died after ABZ therapy, parasite antigen levels fell sharply by 3 months post treatment. This pattern was not observed in patients refractory to treatment. The sensitivity of the assay with serum samples, and its ability to identify successfully treated patients, make this monoclonal antibody-based ELISA the test of choice for the follow-up of NCC cases.

Cysticercosis is a frequent infection in developing countries where pigs are raised [1]. Population-based studies show substantially higher epilepsy rates in developing countries than in industrialized countries, a difference attributed in part to neurocysticercosis [2, 3]. Nevertheless, no estimate of the disease burden due to cysticercosis exists. In this article we estimate, for the first time, the burden of morbidity attributable to cysticercosis in a developing country. Cysticercosis is the larval tissue stage of the pork tapeworm Taenia solium. When humans consume undercooked cysticercotic pork, the larva attaches to the gut wall and grows into the intestinal tapeworm. The life cycle is maintained when pigs eat human feces containing tapeworm eggs and develop porcine cysticercosis, a process facilitated by husbandry practices in villages where pigs are free-roaming scavengers and human fecal contamination is widespread. These life-cycle stages are benign in comparison with those of human cysticercosis, defined by the presence of T. solium larvae in human tissues, which occurs when people ingest tapeworm eggs from food, drink, or soil contaminated by the feces of a tapeworm carrier. Seizures are the most common manifestation of symptomatic human cysticercosis [4–6]. The disease may also be associated with headache, hydrocephalus, chronic meningitis, or symptoms due to a space-occupying central nervous system (CNS) lesion [7]. Isolated nonneurological manifestations, such as ocular or dermal cysts, account for

An enzyme-linked immunosorbent assay (ELISA) for the detection of antigen secreted by viable Taenia solium metacestodes (Ag-ELISA) was applied to 43 pre-treatment and 47 follow-up cerebrospinal fluid (CSF) samples from Peruvian patients with neurocysticercosis demonstrated by computed tomography and enzyme-linked immunoelectrotransfer blot assay. The sensitivity of the assay was 86%. Negative pre-treatment results in the Ag-ELISA test were restricted to patients with only a single live cyst or only enhancing lesions. Patients with hydrocephalus had higher levels of circulating antigen. There was no difference between antigen levels in CSF taken before and immediately after treatment (day 14). Levels of parasite antigen were significantly positively correlated with the number of live cysts detected by tomography and were also proportional to the number and intensity of antibody reactions recognized by the immunoblot diagnostic test. In contrast, there was a negative correlation with the number of enhancing lesions revealed by tomography, supporting the hypothesis that enhancing lesions correspond to a terminal, moribund stage of the parasite. The use of antigen-detection tests specific for viable metacestodes has immediate utility in the clinical context, not only providing important information on the viability of the parasites but also leading to an improved understanding of the pathogenesis of neurocysticercosis before and after drug treatment.

Neurocysticercosis is the main cause of acquired epilepsy in developing countries and is an emerging disease in the United States. Introduction of the immunoblot assay provided a new tool for the diagnosis and monitoring of neurocysticercosis. This study analyzed the relationship between clinical characteristics of cerebral infection (number and type of lesions) plus the baseline response on immunoblot and the changes observed after therapy. Reaction to all 7 diagnostic bands was associated with severe infection (more lesions). Seventeen patients (35%) had no active lesions on computed tomography (CT) 3 months after therapy and were considered cured. Although most cured patients remained seropositive after 1 year, 3 became seronegative before 9 months. In these 3 cases, the lesions had resolved on CT at 3 months. Persistent seropositivity does not necessarily indicate active infection. Serologic follow-up will be clinically helpful only in rare cases in which early antibody disappearance occurs.

Cerebral cysticercosis is the main cause of late-onset epilepsy in most developing countries. Data on the neuroepidemiology of cysticercosis in endemic populations is scarce. In an endemic village on the northern coast of Peru, 49 individuals with neurological symptomatology (41 epileptic and 8 non-epileptic) were screened for antibodies to Taenia solium, using a serum electroimmunotransfer blot assay. Fifteen subjects were seropositive, 14 (34%) of those with epilepsy but only one (13%) of those who were non-epileptic. A history of passing proglottides was associated with positive serology. Thirteen of the 15 seropositive individuals underwent cerebral computed tomography; only 7 (54%) were abnormal. A randomly selected sample of 20 pigs from the village was also tested, and 6 (30%) were seropositive. This study demonstrated the importance of cysticercosis in the aetiology of epilepsy in endemic villages and the close relationship between porcine and human infection.

The current methods of serological diagnosis of hydatidosis include the detection of an antigen-antibody...