Diagnosis and Treatment of Neurocysticercosis: 2017 Clinical Practice Guidelines by the Infectious Diseases Society of America (IDSA) and the American Society of Tropical Medicine and Hygiene (ASTMH).

Abstract

In the first section, the panel summarizes background information relevant to the topic. In the second section, the panel poses questions regarding the diagnosis and treatment of neurocysticercosis (NCC), evaluates applicable clinical trial and observational data, and makes recommendations using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework [1]. The following 27 clinical questions were answered: How should neurocysticercosis be diagnosed? What imaging studies should be used to classify disease? What additional tests should be performed prior to initiation of therapy? How should antiparasitic and anti-inflammatory therapy be monitored? What is the role of antiparasitic drugs in viable parenchymal neurocysticercosis? What is the role of anti-inflammatory therapy in management of viable parenchymal neurocysticercosis? What is the role of antiepileptic drugs in viable parenchymal neurocysticercosis? What follow-up is recommended after initial antiparasitic therapy for patients with viable parenchymal neurocysticercosis? What should be the initial approach to the patient with multiple enhancing lesions from neurocysticercosis? What is the role of antiepileptic medications in patients with single enhancing lesions from cysticercosis with seizures? What is the role of antiparasitic drugs in patients with single enhancing lesions? What is the role of anti-inflammatory therapy in single enhancing lesions? How should patients with single enhancing lesions be followed? What should the initial approach be to patients with calcified lesions suggestive of calcified parenchymal neurocysticercosis? What is the role of antiparasitic drugs, antiepileptic drugs, and anti-inflammatory medications in the management of patients with calcified parenchymal neurocysticercosis? Is there a role for surgical therapy in refractory cases? How are extraparenchymal cysts best identified? What is the optimal approach to management of ventricular neurocysticercosis in the lateral and third ventricles? What is the optimal surgical approach to management of ventricular neurocysticercosis in the fourth ventricles? What is the optimal approach to adherent ventricular neurocysticercosis? Does medical therapy as an adjunct to procedures or as primary therapy have an impact on outcome in treating patients with ventricular neurocysticercosis? What is the role of medical therapy in subarachnoid neurocysticercosis in the basilar cisterns or Sylvian fissures? What is the role of neurosurgery in subarachnoid neurocysticercosis? How is spinal neurocysticercosis best treated? What is the optimal management of ocular cysticercosis? Should children be managed differently than adults? Should management be different in pregnant women? BACKGROUND Neurocysticercosis, caused by the larval form of the cestode parasite Taenia solium, is a major cause of seizure and neurologic disease worldwide and is common among immigrant populations in the United States. Highly endemic regions include Latin America, sub-Saharan Africa, and parts of Asia [2, 3]. In endemic areas, it is linked to approximately 29% of cases of seizures [4]. Estimates suggest that there are >2000 cases per year in the United States, with hospital charges of nearly $100 million per year [5, 6]. Humans can be hosts to both the tapeworm form and larval forms of the parasite. Taeniasis (also termed taeniosis) refers to infestation of the human intestines with the tapeworm form. The tapeworm is acquired by ingestion of undercooked pork. The scolex evaginates and attaches to the intestinal wall, and segments termed proglottids form a long ribbon-like chain referred to as the strobili. The gravid proglottids and eggs are passed in stool. Humans can also develop cysticercosis after ingestion of ova. Cysticercosis refers to infection of the tissues with the larval cyst (or metacestode). Normally, pigs host the cysts, which are acquired by ingestion of ova or proglottids from human feces. However, humans can be infected by ingestion of ova and develop cysticercosis. Neurocysticercosis refers to cysticercosis involving the central nervous system, including the brain parenchyma, ventricles, basilar cisterns, sulci, gyri, spine, and retina. The pathogenesis, natural history, clinical manifestations, and management vary with the location of the cysticerci [3]. For example, the main clinical manifestations vary between different forms of disease (Table 1). Parenchymal NCC typically presents with seizures or headache. Ventricular NCC most often presents with obstructive hydrocephalus. Subarachnoid NCC can present with communicating hydrocephalus, meningitis, stroke, or focal neurologic findings. Mixed forms are also common. Due to the complexity of diagnosis and management, the American Society for Tropical Medicine and Hygiene (ASTMH) and the Infectious Diseases Society of America (IDSA) agreed to jointly develop guidelines for the diagnosis and management of NCC.