Neurocysticercosis in Houston, Texas

Transcription

1 Neurocysticercosis in Houston, Texas An Update Jose A. Serpa, MD, MS, Edward A. Graviss, PhD, MPH, Joseph S. Kass, MD, and A. Clinton White Jr, MD Abstract: Neurocysticercosis, one of the most common parasitic infections of the human nervous system, has emerged as an important infection in the United States. Neurocysticercosis causes significant morbidity associated with acute seizures, chronic epilepsy, and hydrocephalus. We retrospectively identified patients with definitive or probable neurocysticercosis seen at Ben Taub General Hospital, the largest public teaching hospital in Houston, Texas, from September 1997 through December We collected demographic, clinical, therapeutic, and outcome variables. Neurocysticercosis was classified according to the location of cysts in imaging studies. We compared cases with parenchymal and extraparenchymal disease. We included 111 patients (48 had definitive and 63 probable neurocysticercosis). The mean age was 28.6 years (standard deviation, 13.6 yr), and the male to female ratio was 2:1. Most patients (93%) were Hispanic immigrants. Sixty (54%) patients had parenchymal disease, 22 (20%) intraventricular, 13 (12%) subarachnoid disease, and 13 (12%) had calcifications only. Additionally, 2 patients had hydrocephalus only, and 1 had ocular cysticercosis. Thirteen (40%) of 32 patients with parenchymal disease and 3 (30%) of 10 patients with calcifications had relapsed seizures at follow-up. Extraparenchymal disease was associated with longer duration of hospitalization compared with parenchymal disease. No deaths were identified in our series during a median follow-up of 1 year. Neurocysticercosis has emerged as an important parasitic infection in developed countries as a result of increased migration. With current management, mortality is limited, but there continues to be significant morbidity. Further studies of the epidemiology and pathophysiology of the infection are urgently needed to develop better preventive and therapeutic strategies. (Medicine 2011;90: 81Y86) Abbreviations: BTGH = Ben Taub General Hospital, CSF = cerebrospinal fluid, CT = computed tomography, EITB = enzymelinked immunoelectrotransfer blot, HCHD = Harris County Hospital District, ICD9 = International Classification of Diseases, 9th revision, MRI = magnetic resonance imaging, NCC = neurocysticercosis, US = United States, VPS = ventriculoperitoneal shunt. infection is caused by the larval stage of the pork tapeworm Taenia solium, and it is acquired by ingestion of infective eggs excreted by a tapeworm carrier. 10,24 The burden of disease due to NCC has been difficult to define. 2 Definitive diagnosis requires computerized neuroimaging studies or invasive biopsies, which are not frequently available for widespread use in endemic areas. However, NCC has been estimated to cause at least 50,000 deaths worldwide annually. 22 There is significant morbidity associated with acute seizure disorders, chronic epilepsy, and hydrocephalus. 19 NCC has emerged as an important infection in the United States (US). There are more cases of imported NCC in the US than in all other developed countries combined. This has largely been driven by the influx of immigrants from highly endemic regions into the US and widespread access to neuroimaging. 29 Most cases are young Hispanic immigrants from Mexico and Central America. There are also a small number of welldocumented cases of local transmission of NCC. 16,29,30 Despite recent advances, treatment of NCC remains suboptimal at this time. Treatment with the cysticidal agents albendazole and praziquantel has been the topic of numerous reports. 8 Similarly, symptomatic therapy, which includes corticosteroids, antiepileptic drugs, surgical interventions, and general supportive measures, is being increasingly recognized as a critical component in the management of the disease. 15 Our group previously published one of the largest case series of NCC in the US, consisting of 112 patients recorded over 7 years (1985Y1991). 25 Since that time albendazole became available in the US and is now the major antiparasitic drug used in this infection, and new surgical approaches have been developed. There have also been many advances in our understanding of the infection and its management and changes in immigration patterns that could potentially affect many aspects of the epidemiology and outcomes of the disease. In the present study, we update the description of all cases of NCC seen at Ben Taub General Hospital (BTGH), Houston, Texas, from September 1997 through December INTRODUCTION Neurocysticercosis (NCC) is one of the most common parasitic infections of the human nervous system and is the leading cause of acquired epilepsy in low-income countries. The From Department of Medicine, Section of Infectious Diseases (JAS, EAG), and Department of Neurology (JSK), Baylor College of Medicine, Houston; The Methodist Hospital Research Institute (EAG), Houston; and Infectious Diseases Division (ACW), University of Texas Medical Branch at Galveston, Galveston, Texas. Reprints: Jose A. Serpa, MD, Department of Medicine-Section of Infectious Diseases, Baylor College of Medicine, One Baylor Plaza, BCM 286, Room N1319, Houston, TX ( jaserpaa)bcm.edu). Copyright * 2011 by Lippincott Williams & Wilkins ISSN: DOI: /MD.0b013e318206d13e PATIENTS AND METHODS We performed a systematic computer search to identify inpatient and outpatient medical records of all patients with a discharge diagnosis of NCC (International Classification of Diseases, 9th revision EICD9^ code, 129.1) seen at BTGH-Harris County Hospital District (HCHD) from September 1997 through December Definitions Cases were defined as either definitive or probable. Definitive cases had histologic demonstration of the parasite, presence of cystic lesions showing the scolex on computed tomography (CT) or magnetic resonance imaging (MRI), or evidence of subretinal parasites by fundoscopic examination. Probable cases had at least 2 of the following: lesions highly suggestive of NCC Medicine & Volume 90, Number 1, January

2 Serpa et al Medicine & Volume 90, Number 1, January 2011 in imaging studies, positive serum or cerebrospinal fluid (CSF) enzyme-linked immunoelectrotransfer blot (EITB) for anticysticercal antibodies, or clinical manifestations suggestive of NCC. 7 All cases had a history of residence in an area endemic for NCC. Classification The clinical manifestations of NCC are variable depending upon the number, location, and size of the cysticerci and the associated host response. 11 The different forms of infection are usually defined based on neuroradiologic studies. CT scans and MRIs were reviewed and classified according to disease site. 10,25,26 Patients with cysts on neuroimaging studies were classified as parenchymal if cysticerci were located within the parenchyma of the brain or within the folds of the gyri, intraventricular if cysticerci were located inside lateral, third or fourth ventricles, subarachnoid if cysticerci were located in the sylvian fissure or the CSF cisterns at the base of the brain, and ocular if cysticerci were located in any chamber of the eye. Cases with cysts in multiple locations were classified by the least common site (descending order of frequency: parenchymal, ventricular, and subarachnoid). Patients without cysts on imaging studies were classified as having calcifications or hydrocephalus. Radiologic improvement was specifically defined in relation to each type of NCC. Resolution of cystic lesions with or without residual calcifications was used for parenchymal cases, resolution of cystic lesions and hydrocephalus for intraventricular cases, and resolution of hydrocephalus and decrease in size of cysts for subarachnoid disease. Demographic, clinical, therapeutic, and outcome variables were collected and entered into a spreadsheet (Microsoft Excel, Microsoft Corp., Redmond, WA) for storage and analysis. Imaging studies (CT scans and/or MRI) were also carefully reviewed to define the location and extension of the infection. Descriptive analysis of categorical variables was done with the chi-square or the Fisher exact test. Continuous variables were compared by the Student t test or the Mann-Whitney test. In addition, we compared cases with parenchymal and extraparenchymal (intraventricular and/or subarachnoid) disease by univariate analysis. Although a multivariate logistic regression full model was not built due to the small size of our study population, we did control for duration of hospitalization by age, sex, and use of steroids and antihelmintics. Statistical analysis was conducted with STATA 9.2 (StataCorp, College Station, TX). This study was approved by the Institutional Review Board of Baylor College of Medicine and the HCHD Research Office. RESULTS A computer search identified 202 patients with an ICD9 code for NCC. Of those, we excluded 43 patients because they had had a previous hospitalization due to NCC before 1997, given an incorrect ICD9 code, had an alternative diagnosis, or did not meet criteria for a NCC case. Forty-eight patients did not have charts available for review. A total of 111 patients were finally included in the study (48 had definitive NCC and 63 probable NCC). Patients with definitive and probable parenchymal NCC were comparable in terms of symptoms, treatment received, and clinical and radiologic outcome. Thus, they are combined for subsequent analysis. Epidemiology and Diagnosis The mean age was 28.6 years old (standard deviation, 13.6 yr), and the male to female ratio was 2:1. Information on birthplace was available for 70 (63%) patients. Of those with available information, nearly all (93%) were Hispanic immigrants. Mexicans accounted for 77% (54 patients) followed by Hondurans (7%, 5 patients), and El Salvadorans (4%, 3 patients). There were 4 US-born patients; all had a history of either having lived in or travelled to a NCC-endemic area. One patient was co-infected with the human immunodeficiency virus (HIV) and has been described elsewhere. 23 Data about the time elapsed from immigration to the US to admission to the hospital were available for 51 (46%) patients. The median time from immigration to admission was 3 years (interquartile range, 1Y11 yr). Patients with NCC had a median duration of symptoms before admission of 3.5 days (interquartile range, 1Y29 d). Eleven (10%) patients presented with symptoms that had started more than 6 months before admission. All patients underwent imaging studies (CT and/or MRI) of the brain. In contrast, antibody assays were infrequently performed. EITB was performed on serum from 9 patients (8 were positive) and on CSF from 7 patients (4 were positive and 3 yielded negative results). Serum and CSF samples were both tested in only 1 patient. Classification of Neurocysticercosis Sixty (54%) patients had parenchymal disease, 22 (20%) intraventricular, 13 (12%) subarachnoid, and 13 (12%) calcifications only. Additionally there were 2 patients with hydrocephalus but no other identifiable lesions, and 1 case with ocular cysticercosis without brain lesions. Clinical Manifestations, Treatment, and Outcome According to NCC Forms The patients receiving at least 1 neurosurgical intervention due to NCC have been reported previously. 20 For completeness, all patients are included here. Follow-up information was available for 76 (68%) patients (median length of follow-up, 1 yr; interquartile range, 0.27Y2.47). Of those, 47 (64%) patients had at least 1 new imaging study. No deaths were recorded in our series. Parenchymal Cases Forty-nine (82%) patients with parenchymal disease presented with seizures. Headaches (23 patients, 38%) were also common. Only a minority presented with focal neurologic signs (9 patients, 16%). The most common radiologic presentation was a single enhancing cyst (34 patients, 57%) (Figure 1). Thirty-one (52%) patients had concomitant calcifications. Treatment with antiepileptics, corticosteroids, and antihelmintic drugs was administered to 49 (82%), 21 (35%), and 16 (27%) patients, respectively. Of the 16 patients who were treated with antihelmintics, 13 received albendazole 400 mg twice daily for 1Y2 weeks, and 3 received praziquantel 50 mg/kg per day for 2 weeks. Four (7%) patients underwent open craniotomy for removal of parenchymal cysts due to diagnostic uncertainty. Thirteen (40%) of 32 patients, for whom follow-up information was available, had at least 1 additional seizure after being discharged from the hospital. Sixteen (89%) of 18 patients who had at least 1 follow-up imaging study experienced improvement of radiographic lesions. Of those with parenchymal cysticercosis and seizures at presentation, 6/10 (60%) treated with antiparasitic drugs were free from recurrent seizures compared to 13/22 (59%) not treated with antiparasitic drugs (p = 1.0). Similarly, radiologic resolution was noted in 7/7 (100%) treated with antiparasitic drugs compared to 6/7 (86%) not treated (p = 1.0). Patients with single and multiple cysts (median, 2 cysts; interquartile range, 2Y3) had similar 82 * 2011 Lippincott Williams & Wilkins

3 Medicine & Volume 90, Number 1, January 2011 Neurocysticercosis Infection in the US Intraventricular Cases The most common clinical manifestations of intraventricular disease (Figure 2) included headaches, altered mental status, and nausea/vomiting in 18 (82%), 11 (50%), and 10 (45%) patients, respectively. Radiographic evidence of hydrocephalus was recorded in 19 (86%) patients. Medical therapy with corticosteroids and antihelmintics was given to 12 (55%) and 10 (45%) patients, respectively. Of the 10 patients who were treated with antihelmintics, 7 received albendazole 400 mg twice daily for 2 weeks, and 3 received praziquantel 50 mg/kg per day for 2 weeks. Twelve (55%) patients underwent placement of ventriculoperitoneal shunts (VPSs), and of those, 2 experienced shunt failure requiring shunt revision, 1 had a subsequent craniotomy, and 1 required endoscopic resection of cysts. Surgical removal of the cyst was performed in 10 (45%) patients; of those 6 underwent open craniotomy, and 4 neuroendoscopic cystectomy. Fourteen (82%) of 17 patients who had follow-up imaging data available showed improvement of lesions. FIGURE 1. Enhancing parenchymal cystic lesion (arrow) with associated edema. likelihoods of receiving antihelmintics, developing recurrent seizures, or experiencing radiologic resolution. Subarachnoid Cases Eleven (85%) patients with subarachnoid disease (Figure 3) presented with headaches. Common associated symptoms included visual disturbances and nausea/vomiting in 5 (38%) and 4 (31%) cases, respectively. Hydrocephalus was radiologically observed in 7 (54%) patients, whereas arachnoiditis was found in 1 patient. Medical therapy with corticosteroids, antiepileptics, and antihelmintics was administered to 8 (62%), 6 (46%), and 6 (46%) patients, respectively. Of the 6 patients treated with antihelmintics, 5 of them received albendazole 400 mg twice daily for 1 month, and 1 received combination therapy with albendazole and praziquantel. Six (46%) patients also underwent placement of VPSs, and of those, 2 experienced shunt failure requiring shunt revision. One additional patient had resection of cysts by open craniotomy during follow-up. Six (75%) of 8 patients who had follow-up imaging data available experienced improvement of lesions. Patients with definitive and probable subarachnoid NCC were comparable in terms of symptoms, treatment received, and clinical and radiologic outcome. FIGURE 2. Cystic lesion in left frontal horn (arrow) causing dilatation of left lateral ventricle. FIGURE 3. Subarachnoid cysts surrounding the right middle cerebral artery (arrow) and adjacent to the right parietal cortex. * 2011 Lippincott Williams & Wilkins 83

4 Serpa et al Medicine & Volume 90, Number 1, January 2011 Calcifications Only Most common presenting symptoms among patients with calcifications (Figure 4) included seizures and headaches in 10 (77%) and 5 (38%) cases, respectively. Treatment with antiepileptics and corticosteroids was instituted for 11 (85%) and 3 (23%) patients, respectively. Despite not being indicated, 12 antihelmintics were given to 2 (15%) of our patients. Three (30%) of 10 patients for whom follow-up information was available had recurrent seizures. Hydrocephalus Only These 2 patients presented with headaches and visual disturbances, and were both treated with placement of a VPS. Clinical and radiographic resolution of hydrocephalus was documented during follow-up in both cases. Differences Between Parenchymal and Extraparenchymal Neurocysticercosis We compared patients with parenchymal disease (n = 60) and patients with intraventricular and/or subarachnoid (extraparenchymal) disease (n = 35). Cases with calcifications or hydrocephalus only or ocular cysticercosis were excluded from this subanalysis. In the univariate analysis (Table 1), patients with extraparenchymal disease were more likely to be older, with longer duration of hospitalization, and with headaches as their initial presentation compared to patients with parenchymal disease. They were prescribed corticosteroids and antihelmintics more frequently than patients with parenchymal disease. In contrast, patients with parenchymal disease were more likely to be male and to present with seizures. Evidence of radiologic improvement at follow-up was similar between groups. Extraparenchymal disease was associated with a longer duration of hospitalization (odds ratio, 1.18; 95% confidence interval, 1.02Y1.35; p = 0.02) even after controlling for age, sex, and use of steroids and antihelmintics. Only 4 of the parenchymal cases underwent surgical interventions. By contrast, FIGURE 4. Several scattered calcifications (arrows). TABLE 1. Parenchymal and Extraparenchymal Neurocysticercosis Parenchymal (n = 60) Extraparenchymal (n = 35) p Age (yr)* 29.5 (SD, 1.8) 36.7 (SD, 2.1) 0.01 Males 48 (80) 17 (49) G0.01 Time between immigration to US and onset of symptoms (yr) 2(1Y6) 11 (3Y20) 0.08 Duration of 3.3 (SD, 0.5) 11.4 (SD, 1.8) G0.01 hospitalization (d)* Seizures 49/60 (82) 3/32 (9) G0.01 Headaches 23/57 (40) 29/34 (85) G0.01 Use of antihelmintics 16/59 (27) 16/30 (53) 0.02 Use of corticosteroids 21/59 (36) 20/29 (69) G0.01 Radiologic improvement at follow-up 16/18 (89) 20/25 (80) 0.44 *Mean and standard deviation (SD) are displayed for continuous variables. Proportions are shown whenever incomplete collection of data occurred. Median (interquartile range). most cases of ventricular or subarachnoid disease required surgery (either placement of a VPS, endoscopic cystectomy, or open cystectomy). DISCUSSION In the current study, we describe 111 patients with NCC, which represents one of the largest case series of NCC in the US. The age and sex distribution (that is, predominantly young males) observed here was similar to that reported in other large series in the US. 6,25,27,29 Hispanic immigrants continue to be the main group of patients, and this has remained unchanged for at least the last 2 decades. 6,25 These patients constitute a fairly healthy population that would not have presented to the hospital if they had not had neurologic complications from cysticercosis. There are no accurate incidence rates in this ethnic group, in part because of barriers new Hispanic immigrants face when trying to establish medical care, including the language barrier and lack of health insurance. According to the US Census Bureau, the Hispanic population in the US grew from 35.3 million on April 1, 2000, to 46.9 million on July 1, This represents an increase of 11.6 million, and of those approximately 4.3 million were due to international migration. In the state of Texas, the Hispanic population also had a similar increase from 6.7 million in 2000 to 8.9 million in Our hospital is the largest county medical facility in Harris County, the county that includes Houston. Harris County is the nation_s third largest county and has the third largest Hispanic population of any county in the US. Our hospital serves a population of approximately 300,000 uninsured and underinsured, 40% of whom are Hispanics. While autochthonous cases of NCC have also been documented in the US, 16,27,29 the 4 US-born cases recorded in our series likely acquired the infection abroad, in NCC-endemic areas. Based on the length of time between immigration to the US and onset of symptoms, we suggest a minimum incubation period of NCC of approximately 3 years, which is similar to 84 * 2011 Lippincott Williams & Wilkins

5 Medicine & Volume 90, Number 1, January 2011 Neurocysticercosis Infection in the US TABLE 2. Neurocysticercosis in Houston, Previous and Present Reports Classification Previous Report (ref. 25) Present Report Total Parenchymal 73* (65.2) 60 (54.1) 133 (59.6) Intraventricular 12 (10.7) 22 (19.8) 34 (15.3) Subarachnoid 4 (3.6) 13 (11.7) 17 (7.6) Calcifications only 22 (19.6) 13 (11.7) 35 (15.7) Hydrocephalus only 0 2 (1.8) 2 (0.9) Ocular 1 (0.9) 1 (0.9) 2 (0.9) Total 112 (100) 111 (100) 223 (100) *Including 2 patients with normal CT scans who presented with seizures. This patient had ocular and spinal cysticercosis. previous descriptions. 9,29 Although the difference was not significant, patients with extraparenchymal disease had a longer incubation time than those with parenchymal NCC (11 vs. 2 yr; p = 0.08). This finding is intriguing considering the large cystic burden and resulting higher antigen levels in extraparenchymal disease. 21 Perhaps the emergent nature of a seizure that can be caused by a single parenchymal cyst compared with the more indolent course of intracranial hypertension associated with multiple extraparenchymal cysts may explain the difference in Bincubation periods[ between the 2 forms of disease. As expected, most of our patients had an acute onset of symptoms before their presentation to the hospital. This was probably driven by the large number of patients presenting with seizures. However, some subjects may have understated the duration of symptoms to ensure a faster attention in the Emergency Department. Imaging studies have contributed greatly to the increased recognition of the infection. CT has a good sensitivity for parenchymal cysticerci or calcifications; however, it may miss some small lesions, especially those located in the posterior fossa, inside the ventricles, or in the basal cisterns. MRI has better accuracy, although it may miss some small calcifications. 11 Serologic tests played a minor role in the diagnosis of NCC in this series compared with our previous study, where almost half of cases had serologic testing done. Serologic tests generally are confirmatory of results already suspected from neuroimaging. The EITB has been the gold standard serodiagnostic assay since first described by Tsang in This test has excellent specificity, although false positive results are rarely noted with a single pg50 band. The sensitivity is good with multiple lesions, but is 70% or less in patients with a single brain cyst or with just calcifications. 17,28 Not surprisingly the only patient who had a negative EITB in serum had only a single enhancing parenchymal lesion. In addition, the serum EITB assay has a higher sensitivity than the CSF assay. 21 Accordingly, our data appear to corroborate this finding. In our case series, the classification of NCC was based on the location of cysts identified by imaging studies. More than half of the cases had parenchymal cysts. Most presented as a single enhancing lesion on CT or hyperintense lesion on MRI, resembling what has been observed in series from developing countries. 3 Nevertheless, intraventricular and subarachnoid NCC made up more than 20% of our cases. Although these numbers are in concordance with previously reported data in the US, 29 our case series showed a slightly higher percentage of extraparenchymal cases than those recorded in endemic regions. 26 When compared with our previous series, 25 we also observed a slightly higher proportion of patients with intraventricular and subarachnoid disease (Table 2). This is most likely due to the ongoing improvement of diagnostic imaging techniques during the last 15 years. The heterogeneity of the clinical manifestations of NCC correlates with the location and stage of the parasite. Patients with parenchymal cysts presented typically with seizures and headaches, whereas those with extraparenchymal cysts (intraventricular and subarachnoid) presented with symptoms of intracranial hypertension. Calcifications or so-called inactive disease, present in 11% of our cases, continue to be an important cause of morbidity. These lesions may cause either recurrent seizures or severe headaches, making the term Binactive[ somewhat misleading. It has been suggested that symptoms in patients with calcified NCC lesions seem to be associated with the occurrence of transient perilesional edema. 14 The treatment of NCC remains controversial. However, there is a growing consensus that symptomatic therapy including antiepileptic drugs, corticosteroids, and selected surgical procedures aimed at controlling seizures, inflammatory responses, and intracranial hypertension, respectively, should become the initial priority in the management of this infection. 11,24 Accordingly, antiepileptic drugs and corticosteroids were used in approximately 80% and 60% of cases in our series, respectively. Neurosurgical procedures such as insertion of VPSs and removal of cysts through either open craniotomy or endoscopy were also performed for the management of selected NCC cases, particularly those with intraventricular and subarachnoid cysts. Indeed, patients with extraparenchymal NCC had a longer length of hospitalization than those with parenchymal disease (11.4 T 1.8 d vs. 3.3 T 0.5 d, respectively). We have also suggested that in contrast to the high rate of shunt failure seen in NCC, neuroendoscopic procedures for resection of cysts seem to be associated with a higher success rate. 13,18,20 It is noteworthy that in the current series, with aggressive management of increased intracranial pressures, there were no deaths. The mortality rate may have been underestimated due to a lack of follow-up information in 30% of patients and a relatively short follow-up time in the remainder. However, this patient population is largely uninsured and has limited options for hospitalization when ill, but does access the county hospital system when needed for severe illness. Antiparasitic drugs were used in only 40% of patients in the current case series compared with 65% of patients in our previous study. 25 This may reflect the treating physicians_ increased awareness of the limited data to support the use of these drugs for many disease forms. Albendazole was the most commonly prescribed antihelmintic. The fact that about 60% of our patients did not get antiparasitic treatment but still had a similar favorable outcome underscores the importance of aggressive symptomatic management as the key component in the treatment of NCC. Surprisingly, the likelihood of receiving antiparasitic drugs was higher among extraparenchymal cases than parenchymal cases. In a 2006 meta-analysis of parenchymal NCC, Del Brutto and coworkers 8 found that cysticidal drug therapy results in better resolution of viable and degenerating parenchymal cysticerci, lower risk for recurrence of seizures in patients with degenerating cysticerci, and a reduction in the rate of generalized seizures in patients with viable cysticerci. By contrast, the only controlled trial of antiparasitc drugs in extraparenchymal disease, which did not show a faster resolution of cysts with the use of albendazole when compared to placebo, was published after the dates of this study. 5 * 2011 Lippincott Williams & Wilkins 85

6 Serpa et al Medicine & Volume 90, Number 1, January 2011 We also found a high rate of radiologic resolution or improvement of NCC lesions (980%); however, many of these cases did not receive antiparasitic drugs. Resolution has also been noted in placebo arms of controlled trials. We found a high rate of seizure recurrence of up to 40%, which approaches the incidence rates reported in series from endemic countries. 4 We did not find any association between better radiologic or seizure outcomes and use of antiparasitic drugs. While the numbers were small and may have been masked by the effects of adherence to antiepileptic drugs, the rate of seizure recurrence suggests that the effect of antiepileptic or antiparasitic drugs in this condition is not optimal. NCC has emerged as an important parasitic infection in developed countries. Although eradication is an achievable goal, it is still far off on the horizon. 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