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 infec-
tions of the human nervous system, has emerged as an important infec-
tion 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 2005. We collected demographic, clinical, therapeutic, and
outcome variables. Neurocysticercosis was classified according to the
location of cysts in imaging studies. We compared cases with paren-
chymal and extraparenchymal disease.
We included 111 patients (48 had definitive and 63 probable neuro-
cysticercosis). 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%) in-
traventricular, 13 (12%) subarachnoid disease, and 13 (12%) had calcifi-
cations 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 dura-
tion 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 ther-
apeutic strategies.
(Medicine 2011;90: 81Y86)
Abbreviations: BTGH = Ben Taub General Hospital, CSF =
cerebrospinal fluid, CT = computed tomography, EITB = enzyme-
linked immunoelectrotransfer blot, HCHD = Harris County Hospital
District, ICD9 = International Classification of Diseases, 9th
revision, MRI = magnetic resonance imaging, NCC = neurocysti-
cercosis, US = United States, VPS = ventriculoperitoneal shunt.
INTRODUCTION
N
eurocysticercosis (NCC) is one of the most common para-
sitic infections of the human nervous system and is the
leading cause of acquired epilepsy in low-income countries. The
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 re-
quires computerized neuroimaging studies or invasive biopsies,
which are not frequently available for widespread use in en-
demic areas. However, NCC has been estimated to cause at least
50,000 deaths worldwide annually.
22
There is significant mor-
bidity 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 well-
documented cases of local transmission of NCC.
16,29,30
Despite recent advances, treatment of NCC remains sub-
optimal at this time. Treatment with the cysticidal agents
albendazole and praziquantel has been the topic of numerous
reports.
8
Similarly, symptomatic therapy, which includes corti-
costeroids, antiepileptic drugs, surgical interventions, and gen-
eral 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 de-
veloped. There have also been many advances in our under-
standing 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 2005.
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 2005.
Definitions
Cases were defined as either definitive or probable. Defin-
itive 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 2011 www.md-journal.com 81
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 77030 (e-mail: jaserpaa)bcm.edu).
Copyright * 2011 by Lippincott Williams & Wilkins
ISSN: 0025-7974
DOI: 10.1097/MD.0b013e318206d13e
Copyright © 2011 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.