Graciela Cárdenas

Subarachnoidal neurocysticercosis non-responsive to cysticidal drugs: a case series.

BackgroundNeurocysticercosis (NC) is one of the most frequent parasitic diseases of the central nervous system. Cysticidal drugs, albendazole and praziquantel, are generally effective when parasites localize in the parenchyma. In contrast, parasites lodged in the subarachnoid basal cisterns are less responsive to treatment.Case PresentationThe clinical and radiological pictures of six Mexican patients non-respondent to cysticidal treatment are presented.ConclusionsThe possible factors involved in the cysticidal non-response are discussed and hints are provided of potentially useful changes to therapeutic protocols.

Impact of Taenia solium neurocysticercosis upon endocrine status and its relation with immuno-inflammatory parameters

Neurocysticercosis (NC) is a parasitic disease caused by the infiltration of the larval stage of Taenia solium in the central nervous system. Clinical presentations are heterogeneous and particularly depend, on the age and gender of the host. We designed a clinical study to evaluate the hormonal changes associated with neurocysticercosis and the relationships between disease heterogeneity, endocrine and immunological status. A total of 50 patients and 22 healthy subjects were included. A precise clinical and radiological description of disease for each patient was recorded. A broad hormonal profile was assessed for each participant and, in a sub-group of patients, immunological features were also evaluated. Compared with controls, all patients had lower dehydroepiandrosterone (DHEA) concentration; male patients also had lower concentrations of 17β-estradiol and higher concentrations of luteinising hormone (LH). In the clinically severe patients, lower concentrations of progesterone and androstenedione were found in women. Higher concentrations of follicle stimulating hormone (FSH) and lower concentrations of testosterone were found in men when compared with the less clinically severe patients. Significant correlations were found between estradiol and IL-10 in male patients, and between dehydroepiandrosterone (DHEA) and IL-1β, and androstenedione and IL-17 in female patients. To our knowledge the present study constitutes the first demonstration that the presence of T. solium larvae in the central nervous system can modify the host environment by the induction of endocrine and immunological changes. These results provide a stimulating background to analyse the repercussions of these changes on the course of the disease and on patient reproductive health.

Severe cysticercal meningitis: clinical and imaging characteristics.

In disease-endemic areas, severe cysticercal meningitis (SCM) is characterized by intense inflammatory cerebrospinal fluid (CSF) and negative bacterial and fungal cultures. There have been no systematic studies of SCM. We characterized patients with SCM and compare them with neurocysticercosis (NC) patients with mild CSF abnormalities by conducting a nine-year retrospective review at a neurological referral center. Two groups of patients were compared: group A, those with severe CSF pleocytosis > 1,000 cells/mm(3) (n = 12), and group B, those with CSF pleocytosis <or= 1,000 cells/mm(3) (n = 126). All patients had positive CSF results in an enzyme-linked immunosorbent assay for cysticercal antigens and negative CSF cultures for bacteria, fungi, and mycobacteria. Intracranial hypertension, meningeal signs, CSF hypoglycorrachia, and a longer clinical course of NC were more frequently seen in group A. It is likely that SCM often goes unrecognized. Its correct identification may reduce morbidity and risks of unnecessary surgery in patients with chronic NC and CSF shunts.

HUMAN NEUROCYSTICERCOSIS: IN VIVO EXPANSION OF PERIPHERAL REGULATORY T CELLS AND THEIR RECRUITMENT IN THE CENTRAL NERVOUS SYSTEM

abstract:  Human neurocysticercosis (NC) is caused by Taenia solium larvae lodged in the central nervous system. Most cases occur with no, or mild, neurological symptoms. However, in some patients, neuroinflammation is exacerbated, leading to severe forms of the disease. Considering the critical role of regulatory T cells (Tregs) in balancing inflammation in chronic diseases, their participation in restraining the inflammatory response in NC was explored in the present study. The frequency of Tregs and their relationship with the level of the proliferative response, the level of activated lymphocytes, and the cytokines expressed were determined in severe NC patients compared with those from healthy donors. Significantly increased peripheral Tregs (CD4+CD25high and CD4+CD25highFoxP3+, CD4+CD25highCTLA4+, and CD4+CD25high IL10+) and a significant decrease in activated (CD38+ and CD69+) T cells were observed in 19 NC patients versus 10 healthy subjects. Significantly increased Tregs in NC are accompanied by a depressed specific, and non-specific, lymphocyte proliferative response, and they negatively correlate with activated CD4+CD69+ lymphocytes. Treg frequencies were also determined in cerebral spinal fluid for 8 of the 19 NC patients. A positive significant correlation between peripheral and local Tregs was observed. Here, we report for the first time data that support the possible contribution of local and systemic Tregs in limiting neuroinflammation in NC.

New diagnostic criteria for neurocysticercosis: Reliability and validity

The diagnosis of neurocysticercosis (NCC) remains problematic because of the heterogeneity of its clinical, immunological, and imaging characteristics. Our aim was to develop and assess a new set of diagnostic criteria for NCC, which might allow for the accurate detection of, and differentiation between, parenchymal and extraparenchymal disease.

Medical Treatment for Neurocysticercosis: Drugs, Indications and Perspectives

Neurocysticercosis is one of the most frequent parasitic diseases affecting the central nervous system. The introduction of anticysticidal therapy in the early 80s and the concomitant improvement of the radiological techniques have lead to apparently significant progress in patient prognosis. However, due to the specificity of the disease, a great debate has been generated on the real usefulness of cysticidal drugs. This article revises and discusses the pharmacological aspects of cysticidal treatment and summarizes current indications for the different types of the disease.

Regulatory T Cells: Molecular Actions on Effector Cells in Immune Regulation

T regulatory cells play a key role in the control of the immune response, both in health and during illness. While the mechanisms through which T regulatory cells exert their function have been extensively described, their molecular effects on effector cells have received little attention. Thus, this revision is aimed at summarizing our current knowledge on those regulation mechanisms on the target cells from a molecular perspective.

Cysticerci Drive Dendritic Cells to Promote In Vitro and In Vivo Tregs Differentiation

Regulatory T cells (Tregs) play a crucial role in immune homeostasis. Treg induction is a strategy that parasites have evolved to modulate the hosts inflammatory environment, facilitating their establishment and permanence. In human Taenia solium neurocysticercosis (NC), the concurrence of increased peripheral and central Treg levels and their capacity to inhibit T cell activation and proliferation support their role in controlling neuroinflammation. This study is aimed at identifing possible mechanisms of Treg induction in human NC. Monocyte-derived dendritic cells (DC) from healthy human donors, cocultivated with autologous CD4+ naïve cells either in the presence or absence of cysticerci, promoted CD25highFoxp3+ Treg differentiation. An increased Treg induction was observed when cysticerci were present. Moreover, an augmentation of suppressive-related molecules (SLAMF1, B7-H1, and CD205) was found in parasite-induced DC differentiation. Increased Tregs and a higher in vivo DC expression of the regulatory molecules SLAMF1 and CD205 in NC patients were also found. SLAMF1 gene was downregulated in NC patients with extraparenchymal cysticerci, exhibiting higher inflammation levels than patients with parenchymal parasites. Our findings suggest that cysticerci may modulate DC to favor a suppressive environment, which may help parasite establishment, minimizing the excessive inflammation, which may lead to tissue damage.

Tuberculous brain abscesses in immunocompetent patients: management and outcome.

BACKGROUND:Tuberculosis (TB) remains an important public health problem in developing countries. OBJECTIVE:To evaluate the clinical presentation, management, and long-term outcome in 6 patients with tuberculous brain abscesses (TBA), an uncommon form of central nervous system (CNS) TB. METHODS:A search of medical records of a single referral neurological center in Mexico City from 2002 to 2007 retrieved 149 patients with CNS TB; 6 of them (4%) met Whiteners criteria for TBA and were included in this review. RESULTS:Five of six patients had a previous history of TB. Three patients were referred to our center under antituberculous treatment (ATT) for pulmonary and lymph node TB, and two patients were receiving ATT for TB meningitis at diagnosis of TBA. All presented with symptoms of intracranial hypertension and hemiparesis. On imaging studies, 3 patients had a single, deep multiloculated lesion and another three had separated lesions, all patients underwent surgery and received long courses of ATT. One patient died after surgery and the rest recovered with moderate to severe neurological sequelae. The residual lesions in 5 patients resolved in follow-up CT or MRI studies at a mean time of 10 months. CONCLUSIONS:Early surgery confirms the diagnosis of TBA. Some patients may require additional surgical procedures if enlargement or recurrence of the lesion occurs. No evidence of drug resistance was found in our cases, and we found only two reports of TBA with primary resistance to ATT in a selective literature review. TBA does not seem to be a consequence of drug resistance. Sequelae are common, and long-term ATT with close clinical and imaging follow-up is mandatory.

Neurological events related to influenza A (H1N1) pdm09.

To review neurological complications after the influenza A (H1N1) pdm09, highlighting the clinical differences between patients with post‐vaccine or viral infection.