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

Taenia solium cysticercosis

Taenia solium cysticercosis.

Neurocysticercosis is now recognized as a common cause of neurologic disease in developing countries and the United States. The pathogenesis and clinical manifestations vary with the site of infection and accompanying host response. Inactive infection should be treated symptomatically. Active parenchymal infection results from an inflammatory reaction to the degenerating cysticercus and will also respond to symptomatic treatment. Controlled trials have not demonstrated a clinical benefit for antiparasitic drugs. Ventricular neurocysticercosis often causes obstructive hydrocephalus. Surgical intervention, especially cerebrospinal fluid diversion, is the key to management of hydrocephalus. Shunt failure may be less frequent when patients are treated with prednisone and/or antiparasitic drugs. Subarachnoid cysticercosis is associated with arachnoiditis. The arachnoiditis may result in meningitis, vasculitis with stroke, or hydrocephalus. Patients should be treated with corticosteroids, antiparasitic drugs, and shunting if hydrocephalus is present.

Neurocysticercosis: Updates on Epidemiology, Pathogenesis, Diagnosis, and Management

Neurocysticercosis, which is caused by infestation of the human CNS with the tissue cysts of Taenia solium, is arguably the most common parasitic disease of the human nervous system. While most of the details of the parasite's life cycle were known by the nineteenth century and most of the clinical manifestations of T. solium infection had been identified by the mid-twentieth century, concepts regarding the prevalence of infection, associated morbidity and mortality, treatment, and epidemiology have changed dramatically over the past 10 years. The increased ease of international travel, the increasing numbers of immigrants from developing countries, and the widespread use of improved diagnostic techniques have led to widespread recognition of neurocysticercosis as a common infection not only in developing countries but also in the United States. Large case series have been reported in the southwestern United States and other areas with large immigrant populations from Latin America [2-7]. Since neurocysticercosis is not a reportable disease, the total number of cases diagnosed in the United States is not known but is estimated at >1,000 new cases each year [2], and this number appears to be increasing. While most of these cases occur in patients infected in developing countries, the number of locally acquired infections is also increasing. The ancient Greeks recognized that intestinal tapeworms were associated with ingestion of meat. They referred to the "hailstones" in meat as cysticerci, meaning bladder-tails. During the nineteenth century, Leuckart identified the complete life cycle of T. solium and noted that human cysticercosis resulted from ingestion of parasite eggs shed by tapeworm carriers. Neurocysticercosis was a frequent finding in autopsy series reported from Europe in the nineteenth century. Studies

Neurocysticercosis: A major cause of neurological disease worldwide

Neurocysticercosis (NC) remains a major public health problem in developing and some developed countries. Currently, the best procedures for diagnosing NC are neuroimaging studies. Immunoserologic assays, such as enzyme-linked immunoelectrotransfer blot assay (EITB) or enzyme-linked immunosorbent assay (ELISA), detect antibodies against Taenia solium, or cysticercus. Consequently, they are useful in identifying a population at risk of contact with the parasite but do not necessarily indicate a systemic active infection. Most seropositive individuals are asymptomatic. No data from prospective studies concern the proportion of these individuals that will develop seizures or other neurologic symptoms. There is a discrepancy between the results of serologic assays and neuroimaging studies: >50% of those individuals with NC diagnosed by computed tomography (CT) scan test EITB negative. Pathophysiologic classification of NC into active, transitional, and inactive forms permits a good correlation between clinical manifestations and neuroimaging procedures and facilitates medical and surgical management and research. The most frequent clinical manifestations of NC are seizures. We assume that NC is the main cause of symptomatic epilepsy in developing countries; however, no case-control or cohort studies demonstrate this association. Most patients with NC with seizures have a good prognosis; nevertheless, further studies analyzing factors related to recurrence of seizures and possibilities of discontinuation of antiepileptic medications (AEDs) are needed. Regarding treatment of NC with antihelminthic drugs, no controlled clinical trials exist that establish specific indications, definitive doses, and duration of treatment. The most effective approach to taeniasis/cysticercosis infection is prevention. This should be a primary public health focus for developing countries. We critically review the available information regarding the epidemiology and diagnosis of human cysticercosis, the physiopathology and imaging correlation of the parasite in the central nervous system (CNS) of the host, the relation between seizures or epilepsy and NC, and the issues surrounding the treatment and prognosis of NC, including the use of antihelminthic therapy.

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Cysticercosis and epilepsy: a critical review.

We compared a plate enzyme-linked immunosorbent assay (ELISA) with an immunoblot--or enzyme-linked immunoelectrotransfer blot--assay (EITB) for the identification of cases of human neurocysticercosis due to Taenia solium and of risk factors for this disease in two Mexican villages. Findings related to age- and sex-specific seroprevalence, risk factors for transmission, and associated morbidity differed significantly according to the assay used. Rates of EITB positivity were significantly higher among persons with a history of convulsions than among those without such a history (29% vs 8%; P < .05); in contrast, ELISA results were negative for all persons with a history of convulsions. The association of seizures with neurocysticercosis in this population was strengthened by the higher rate of abnormal findings compatible with neurocysticercosis on computed tomography of the brain among individuals with a history of convulsions than among those without such a history (70% vs 14%; P < .001). In summary, EITB was more sensitive and specific than ELISA for epidemiological studies of neurocysticercosis.

Community-Based Epidemiological Investigations of Cysticercosis Due to Taenia solium: Comparison of Serological Screening Tests and Clinical Findings in Two Populations in Mexico

A. Plancarte

Papers

Community-Based Epidemiological Investigations of Cysticercosis Due to Taenia solium: Comparison of Serological Screening Tests and Clinical Findings in Two Populations in Mexico