HIV infection and seizures

Early Initiation of Antiretroviral Therapy is Protective Against Seizures in Children With HIV in Zambia: A Prospective Case-Control Study

BACKGROUND

Seizures are relatively common among children with HIV in low- and middle-income countries and are associated with significant morbidity and mortality. Early treatment with antiretroviral therapy (ART) may reduce this risk by decreasing rates of central nervous system infections and HIV encephalopathy.

METHODS

We conducted a prospective, unmatched case-control study. We enrolled children with new-onset seizure from University Teaching Hospital in Lusaka, Zambia and 2 regional hospitals in rural Zambia. Controls were children with HIV and no history of seizures. Recruitment took place from 2016 to 2019. Early treatment was defined as initiation of ART before 12 months of age, at a CD4 percentage >15% in children aged 12-60 months or a CD4 count >350 cells/mm 3 for children aged 60 months or older. Logistic regression models were used to evaluate the association between potential risk factors and seizures.

RESULTS

We identified 73 children with new-onset seizure and compared them with 254 control children with HIV but no seizures. Early treatment with ART was associated with a significant reduction in the odds of seizures [odds ratio (OR) 0.04, 95% confidence interval: 0.02 to 0.09; P < 0.001]. Having an undetectable viral load at the time of enrollment was strongly protective against seizures (OR 0.03, P < 0.001), whereas history of World Health Organization Stage 4 disease (OR 2.2, P = 0.05) or CD4 count <200 cells/mm 3 (OR 3.6, P < 0.001) increased risk of seizures.

CONCLUSIONS

Early initiation of ART and successful viral suppression would likely reduce much of the excess seizure burden in children with HIV.

Clinical characteristics and outcomes after new-onset seizure among Zambian children with HIV during the antiretroviral therapy era

OBJECTIVE

This study describes clinical profiles including human immunodeficiency virus (HIV) disease history and seizure etiology among children living with HIV presenting with new-onset seizure during the era of antiretroviral therapy (ART) in Zambia. 30-day mortality and cause of death are also reported.

METHODS

Children living with HIV (CLWHIV) with new-onset seizures were prospectively evaluated at one large urban teaching hospital and two non-urban healthcare facilities. Interviews with family members, review of medical records, and where needed, verbal autopsies were undertaken. Two clinicians who were not responsible for the patients' care independently reviewed all records and assigned seizure etiology and cause of death with adjudication as needed.

RESULTS

From April 2016 to June 2019, 73 children (49 urban, 24 rural) were identified. Median age was 6 years (IQR 2.2-10.0) and 39 (53%) were male children. Seizures were focal in 36 (49%) and were often severe, with 37% presenting with multiple recurrent seizures in the 24 hours before admission or in status epilepticus. Although 36 (49%) were on ART at enrollment, only 7 of 36 (19%) were virally suppressed. Seizure etiologies were infectious in over half (54%), with HIV encephalitis, bacterial meningitis, and tuberculous meningitis being the most common. Metabolic causes (19%) included renal failure and hypoglycemia. Structural lesions identified on imaging accounted for 10% of etiologies and included stroke and non-accidental trauma. No etiology could be identified in 12 (16%) children, most of whom died before the completion of clinical investigations. Twenty-two (30%) children died within 30 days of the index seizure.

SIGNIFICANCE

Despite widespread ART roll out in Zambia, new-onset seizure in CLWHIV occurs in the setting of advanced, active HIV disease. Seizure severity/burden is high as is early mortality. Enhanced programs to assure early ART initiation, improve adherence, and address ART failure are needed to reduce the burden of neurological injury and premature death in CLWHIV.

Seizure in HIV-infected patients: clinical presentation, cause and treatment outcome in Ethiopia-a retrospective study

BACKGROUND

The estimated number of adult patients living with HIV infection in Ethiopia in 2012 was approximately 800,000. Seizure occurs in 2 to 3% and 6.1% to 34.3% in patients with HIV infection and patients with neurological complications of HIV infection, respectively. Studies on HIV infection and seizure are rare in Ethiopia. The purpose of this study was to assess clinical presentation, cause and treatment outcome of patients with HIV infection presented with seizure.

METHODS

In this retrospective study, patients aged ≥ 13 years with HIV infection presented with seizure were included. Medical records were reviewed and demographic and clinical data were collected.

RESULTS

Records of 146 patients were analysed. Males were 55.5% and the mean age was 34 years. The diagnosis of HIV infection was made after current hospital admission in 69% of patients. Almost all patients (98.6%) had stage 4 HIV infection with very low CD4 count (mean = 77/mm³). In almost all patients seizure was a recent onset at current admission; either it started after admission (42.5%) or within 3 months prior to admission (52.5%). The types of seizures were: generalized tonic-clonic seizure [GTCS] (69.2%), focal motor with secondarily generalization [FMWSG] (19.9%) and simple focal motor (11%). The common causes of seizure were: cerebral toxoplasmosis (46%), tuberculous meningitis (35.6%) and cryptococcal meningitis (13.7%). Case-fatality was 53% and predictors of mortality were: seizure started after admission, change in mentation and comatose at initial evaluation.

CONCLUSIONS

Most patients had stage 4 HIV infection with very low CD4 count and a recent onset seizure which started within 3 months at initial evaluation. GTCS was the commonest seizure type and most causes of seizure were central nervous system opportunistic infections. The case-fatality was high and change in sensorium was an independent predictor of mortality. To prevent the high mortality and morbidity prevention of HIV infection, early diagnosis and treatment, improving diagnostic facilities and access to non-enzyme inducing antiepileptic drugs are recommended.

New-onset focal seizure as a presenting feature of HIV infection: a case report and mini review to the challenge in resource-limited settings

BACKGROUND

The frequency of new-onset HIV-associated seizure in the HIV-infected patient is estimated to be between 2 and 11%. Identifying the underlying etiology of new-onset seizure will have a vital impact on the mortality and morbidity of patients living with HIV infection.

CASE PRESENTATION

We report a 34-year old newly diagnosed HIV+ male patient presented with abnormal body movement (ABM) involving his right hemibody associated with loss of consciousness lasting few minutes of two weeks duration. The ABM occurred frequently (> five times per week) and associated with frothy and excessive salivation. He reported headache following each spells. Brain magnetic resonance imaging (MRI) showed bilateral frontal T2 and FLAIR hyperintensity and T1 hypointensity; post contrast study showed bilateral small ring enhancing lesion with perilesional oedema, the biggest one on the left hemisphere, with a 10 mm diameter; considering patient advanced immunosuppression and underlying HIV infection, the brain MRI findings were consistent with cerebral toxoplasmosis. Bipolar montage electroencephalography (EEG) study showed generalized background slowing, prominent in the left fronto-centeral region. Patient was managed with combination antiretroviral therapy, anti-toxoplasmosis medication, and anticonvulsant. On follow up, the frequency of seizure attack has significantly reduced.

CONCLUSION

Considering the high prevalence of HIV infection and associated seizure among people living with HIV in sub-Saharan Africa, this case fairly highlights on the importance of utilizing advanced imaging techniques such as MRI and EEG in identifying the underlying causes of HIV-associated seizures.

Viral infections and their relationship to neurological disorders

The chronic dysfunction of neuronal cells, both central and peripheral, a characteristic of neurological disorders, may be caused by irreversible damage and cell death. In 2016, more than 276 million cases of neurological disorders were reported worldwide. Moreover, neurological disorders are the second leading cause of death. Generally, the etiology of neurological diseases is not fully understood. Recent studies have related the onset of neurological disorders to viral infections, which may cause neurological symptoms or lead to immune responses that trigger these pathological signs. Currently, this relationship is mostly based on epidemiological data on infections and seroprevalence of patients who present with neurological disorders. The number of studies aiming to elucidate the mechanism of action by which viral infections may directly or indirectly contribute to the development of neurological disorders has been increasing over the years but these studies are still scarce. Comprehending the pathogenesis of these diseases and exploring novel theories may favor the development of new strategies for diagnosis and therapy in the future. Therefore, the objective of the present study was to review the main pieces of evidence for the relationship between viral infection and neurological disorders such as Alzheimer's disease, Parkinson's disease, Guillain-Barré syndrome, multiple sclerosis, and epilepsy. Viruses belonging to the families Herpesviridae, Orthomyxoviridae, Flaviviridae, and Retroviridae have been reported to be involved in one or more of these conditions. Also, neurological symptoms and the future impact of infection with SARS-CoV-2, a member of the family Coronaviridae that is responsible for the COVID-19 pandemic that started in late 2019, are reported and discussed.

Epilepsy management in pregnant HIV+ women in sub-Saharan Africa, clinical aspects to consider: a scoping review

BACKGROUND

Since the introduction of highly active antiretroviral therapy (HAART), acquired immune deficiency syndrome (AIDS) related mortality has markedly declined. As HAART is becoming increasingly available, the infection with human immunodeficiency virus (HIV+) in sub-Saharan Africa (SSA) is becoming a chronic condition. While pregnancy in HIV+ women in SSA has always been considered a challenging event for the mother and the fetus, for pregnant HIV+ women also diagnosed with epilepsy (WWE), there are additional risks as HIV increases the odds of developing seizures due to the vulnerability of the central nervous system to other infections, immune dysfunction, and overall metabolic disturbances. In light of a growing proportion of HIV+ WWE on HAART and an increasing number of pregnant women accessing mother-to-child transmission of HIV programs through provision of HAART in SSA, there is a need to develop contextualized and evidenced-based clinical strategies for the management of epilepsy in this population. In this study, we conduct a literature scoping review to identify issues that warrant consideration for clinical management.

RESULT

Twenty-three articles were retained after screening, which covered six overarching clinical aspects: status epilepticus (SE), Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN), dyslipidemia, congenital malformation (CM), chronic kidney disease (CKD), and neurological development. No studies for our population of interest were identified, highlighting the need for a cautionary approach to be employed when extrapolating findings.

CONCLUSION

High risks of CM and drug interactions with first-line antiepileptic drugs (AEDs) warrant measures to increase the accessibility and choices of safer second-line AEDs. To ensure evidence-based management of epilepsy within this population, the potential high prevalence of SE, CKD, dyslipidemia, and SJS/TEN and the cumulative effect of drug-drug interactions should be considered. Further understanding of the intersections between pregnancy and drug-drug interactions in SSA is needed to ensure evidenced-based management of epilepsy in pregnant HIV+ WWE. To prevent SE, the barriers for AED treatment adherence in pregnant HIV+ women should be explored. Our review underscores the need to conduct cohort studies of HIV+ WWE in reproductive age over time and across pregnancies to capture the cumulative effect of HAART and AED to inform clinical management.

Neurological disorders in HIV in Africa: a review

BACKGROUND

Neurological disorders in HIV infection are a common cause of morbidity and mortality. The aim of this paper is to provide a narrative overview of up to date information concerning neurological disorders affecting HIV infected persons in Africa.

METHODS

Seminal research concerning neurological disorders among HIV-infected adults in sub-Saharan Africa from prior to 2000 was combined with an in-depth search of PubMed to identify literature published from 2000 to 2017. The following Mesh terms were used. "Nervous System Diseases" "HIV Infections" and "Africa South of the Sahara" and "Seizures" or "Spinal Cord Diseases" or "Peripheral Nervous System Diseases" or "AIDS Dementia Complex" or "Opportunistic Infections" or "Immune Reconstitution Inflammatory Syndrome" or "Stroke". Only those articles written in English were used. A total of 352 articles were identified, selected and reviewed and 180 were included in the study. These included case series, observational studies, interventional studies, guidelines and reviews with metanalyses. The author also included 15 publications on the subject covering the earlier phase of the HIV epidemic in Africa from 1987 to 1999 making a total of 195 references in the study. This was combined with extensive personal experience diagnosing and treating these neurological disorders.

RESULTS

Neurological disorders were common, typically occurring in WHO stages III/IV. These were in three main categories: those arising from opportunistic processes mostly infections, direct HIV infection and autoimmunity. The most common were those arising from direct HIV infection occurring in >50%. These included HIV-associated neurocognitive dysfunction (HAND), neuropathy and myelopathy. Opportunistic infections occurred in >20% and frequently had a 6-9-month mortality rate of 60-70%. The main causes were cryptococcus, tuberculosis, toxoplasmosis and acute bacterial meningitis. Concurrent systemic tuberculosis occurred in almost 50%.

CONCLUSION

Neurological disorders are common in HIV in Africa and the main CNS opportunistic infections result in high mortality rates. Strategies aimed at reducing their high burden, morbidity and mortality include early HIV diagnosis and anti-retroviral therapy (ART), screening and chemoprophylaxis of main opportunistic infections, improved clinical diagnosis and management and programme strengthening.

Inpatient Outcomes After Elective Lumbar Spinal Fusion for Patients with Human Immunodeficiency Virus in the Absence of Acquired Immunodeficiency Syndrome

BACKGROUND

To our knowledge, no prior study has evaluated outcomes after elective lumbar spinal surgery in human immunodeficiency virus (HIV) patients without acquired immunodeficiency syndrome (AIDS). This review investigated the impact of HIV-positive status (without AIDS) on outcomes after elective lumbar fusion for degenerative disc disease (DDD).

METHODS

Adult patients registered in the Nationwide Inpatient Sample (2002-2011) undergoing elective lumbar fusion for DDD were extracted. Multivariable regression techniques were used to explore the association of HIV positivity with outcomes after lumbar fusion.

RESULTS

This cohort included 612,000 hospitalizations (0.07% were HIV positive) of lumbar fusion for DDD. Compared with HIV-negative patients undergoing lumbar fusion, HIV-positive patients were younger (47 vs. 55 years), male (61% vs. 42%), largely insured by Medicare (30% vs. 5%), and had higher rates of chronic obstructive pulmonary disease (23.7% vs. 14.6%) (all P < 0.001) but had lower rates of obesity, hypertension, and diabetes (all P < 0.001). Multivariable models demonstrated HIV positivity to be associated with higher odds for an adverse event (odds ratio [OR], 1.92; P < 0.001), in-hospital mortality (OR, 39.91; P < 0.001), wound complications (OR, 2.60; P = 0.004), respiratory (OR, 5.43; P < 0.001) and neurologic (OR, 1.96; P = 0.039) complications, and higher costs (7.1% higher; P = 0.011) compared with non-HIV patients. There were no differences in thromboembolic events, cardiac or gastrointestinal complications, discharge disposition, or length of stay.

CONCLUSIONS

Even in this selected cohort of well-controlled HIV patients, there were high complications, with concerning rates of death and respiratory complications. These data shed new light on elective spine surgery in HIV patients and may influence the treatment algorithm of surgeons who are familiar with older papers.

Seizures in HIV: The case for special consideration

Purpose

This study aimed to determine the rate, cause and management of seizures in the context of potential ART–ASD interactions in a cohort of HIV + individuals.

Methods

Records of 604 HIV + patients were reviewed and those reporting epilepsy/seizure diagnosis were further evaluated.

Results

This cohort exhibited a seizure rate of 2.4%. HIV + patients treated for epilepsy displayed low serum ASD levels and failed to achieve seizure control. They were more likely to disengage from Neurology follow-up.

Conclusion

For HIV + patients presenting with seizures/epilepsy the ASD prescription and the provision of supplementary support services needs to be carefully considered.

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ID and Neurology services should be involved in the evaluation and treatment of seizures in the context of HIV infection.

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ART-ASD interactions could have been the cause of ineffective treatment and other poor outcomes in this small cohort.

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In this group of patients it is important to apply published guidelines when it comes to making treatment decisions.

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Counseling and supportive services need to be provided to ensure engagement with services and adherence to treatment.

New-onset seizure in HIV-infected adult Zambians: A search for causes and consequences

OBJECTIVE

To identify the etiology of new-onset seizure in HIV-infected Zambian adults and identify risk factors for seizure recurrence.

METHODS

A prospective cohort study enrolling HIV-infected adults with new-onset seizure within 2 weeks of index seizure obtained clinical, laboratory, and neuroimaging data to determine seizure etiology. Participants were followed to identify risk factors for seizure recurrence. Risk factors for mortality were examined as mortality rates were unexpectedly high.

RESULTS

Eighty-one patients with CSF for analysis were enrolled and followed for a median of 306 days (interquartile range 61-636). Most (91%) were at WHO stage III/IV and 66 (81%) had a pre-seizure Karnofsky score ≥50. Prolonged or multiple seizures occurred in 46 (57%), including 12 (15%) with status epilepticus. Seizure etiologies included CNS opportunistic infections (OI) in 21 (26%), hyponatremia in 23 (28%), and other infections in 8 (10%). OIs included Cryptococcus (17%), JC virus (7%) and 5% each for tuberculosis, cytomegalovirus, and varicella-zoster virus. No etiology could be identified in 16 (20%). Thirty (37%) patients died during follow-up and 20 (25%) had recurrent seizures with survival being the only identifiable risk factor.

CONCLUSIONS

HIV-infected adults with new-onset seizure in Zambia often have advanced HIV disease with OI being the most frequent seizure etiology. Seizure recurrence is common but no risk factors for recurrence other than survival were identified. These findings suggest an urgent need for immune reconstitution in this population. Initiating treatment for seizure prophylaxis where only enzyme-inducing antiepileptic medications are available could threaten antiretroviral efficacy.

Role of cranial computed tomography in human immunodeficiency virus-positive patients with generalised seizures

Background: Emergency neuroimaging of human immunodeficiency virus (HIV)-positive patients with generalised new onset seizures (NOS) and a normal post-ictal neurological examination remains controversial, with the general impression being that emergency imaging is necessary because immunosuppression may blur clinical indicators of acute intracranial pathology. The objectives of our study were to establish whether cranial computed tomography (CT) affects the emergency management of HIV-positive patients with generalised NOS and a normal post-ictal neurological examination.Method: We conducted a prospective descriptive observational study. Consecutive HIVpositive patients of 18 years and older, who presented to the Kimberley Hospital Complex’s Emergency Department within 24 hours of their first generalised seizures and who had undergone normal post-ictal neurological examinations, were included. Emergency CT results as well as CD4-count levels were evaluated.Results: A total of 25 HIV-positive patients were included in the study. The results of cranial CT brought about a change in emergency care management in 12% of patients, all of them with CD4 counts below 200 cells/mm3 .Conclusion: We suggest that emergency cranial CT be performed on all HIV-positive patients presenting with generalised NOS and a normal post-ictal neurological examination, particularly if the CD4 count is below 200 cells/mm3.Keywords: HIV; Seizures; CT Brain

Why the communicable/non-communicable disease dichotomy is problematic for public health control strategies: implications of multimorbidity for health systems in an era of health transition

In today's globalized world, rapid urbanization, mechanization of the rural economy, and the activities of trans-national food, drink and tobacco corporations are associated with behavioral changes that increase the risk of chronic non-communicable diseases (NCDs). These changes include less healthy diet, lower physical activity, tobacco smoking and increased alcohol consumption. As a result, population health profiles are rapidly changing. For example, the global burden of type 2 diabetes mellitus is expected to double by 2030, with 80% of adult cases occurring in low and middle-income countries (LMIC). Many LMIC are undergoing rapid changes associated with developing high rates of NCD while concomitantly battling high levels of certain communicable diseases, including HIV, TB and malaria. This has population health, health systems and economic implications for these countries. This critical review synthesizes evidence on the overlap and interactions between established communicable and emerging NCD epidemics in LMIC. The review focuses on HIV, TB and malaria and explores the disease-specific interactions with prevalent NCDs in LMIC including diabetes, cardiovascular disease, chronic obstructive pulmonary disease, chronic renal disease, epilepsy and neurocognitive diseases. We highlight the complexity, bi-directionality and heterogeneity of these interactions and discuss the implications for health systems.

HIV and new onset seizures: slipping through the cracks in HIV care and treatment

OBJECTIVES

The aim of the study was to describe patient characteristics and outcomes among HIV-positive adults presenting to a Zambian tertiary care hospital with new-onset seizures.

METHODS

From July 2011 to June 2013, adults with seizures and a known or probable diagnosis of HIV infection were screened for a cohort study. Demographic and clinical data were obtained, including information on engagement in HIV services and in-patient mortality. Analyses were conducted to identify characteristics associated with poor engagement in care and death.

RESULTS

A total of 320 of 351 screened adults were HIV-positive, with 268 of 320 experiencing new-onset seizures. Of these, 114 of 268 (42.5%) were female, and their mean age was 36.8 years. Seventy-nine of the 268 patients (29.5%) were diagnosed with HIV infection during the index illness. Among those who were aware of their HIV-positive status, 59 of 156 (37.8%) had disengaged from care. Significant functional impairment (Karnofsky score < 50) was evident in 44.0% of patients. Cerebrospinal fluid was not obtained in 108 of 268 (40.3%). In-patient mortality outcomes were available for 214 patients, and 47 of these 214 (22.0%) died during hospitalization. Patients with significant functional impairment were more likely to undergo lumbar puncture (P = 0.046). Women and the functionally impaired were more likely to die (P = 0.04 and < 0.001, respectively).

CONCLUSIONS

Despite the availability of care, less than half of HIV-infected people with new-onset seizures were actively engaged in care and in-patient mortality rates were high. In the absence of clinical contraindication, lumbar puncture should be performed to diagnose treatable conditions and reduce morbidity and mortality. Continued efforts are needed to expand community-based testing and improve HIV care retention rates. Qualitative studies are needed to elucidate factors contributing to lumbar puncture usage in this population.

Cognitive impairment and psychiatric morbidity in HIV+ Zambians with new-onset seizure

A prospective cohort study of new-onset seizure in people with human immunodeficiency virus (HIV) in Zambia is ongoing to determine the incidence of subsequent epilepsy and risk factors for epileptogenesis in this population. At enrollment, we evaluated this cohort for cognitive impairment and psychiatric morbidity. Over 50% of participants had cognitive impairment and significant psychiatric morbidity. Most participants had advanced HIV disease based on CD4+ T-cell count and World Health Organization stage, but we found no association between cognitive impairment or psychiatric morbidity and HIV disease staging.

The EEG of tropical encephalopathies

In addition to encountering most of the conditions treated by clinicians in the West, clinicians in the tropics are faced with unique tropical encephalopathies. These are largely but not entirely infectious in nature. Despite the relatively low cost of EEG technology, it remains unavailable in many low-income tropical settings even at the tertiary care level. Where available, the EEG recordings and interpretation are often of unacceptable quality. Nonetheless, there are existing data on the EEG patterns seen in malaria and a number of tropical viral, bacterial, and parasitic infestations.

Review on plants with CNS-effects used in traditional South African medicine against mental diseases

The majority of the population in South Africa use traditional health care to treat various mental conditions. In this review, we present ethnobotanical information on plants used by the traditional healers in South Africa to treat mental illnesses, specifically epilepsy, depression, age-related dementia and debilitative mental disorders. Details of the recent scientific studies conducted on some of these plants are reviewed. Extracts of Searsia chirindensis, Cotelydon orbiculata and Leonotis leonurus have shown in vivo anticonvulsant activity. Extracts from Searsia dentata and Searsia pyroides showed spontaneous epileptiform discharge in mouse cortical slices, and acted as NMDA-receptor antagonists. Apigenin, amentoflavone and agathisflavone with affinity to the benzodiazepine site on the GABA(A)-receptor were isolated from Searsia pyroides. Naringenin with affinity to the GABA(A)-benzodiazepine receptor was isolated from Mentha aquatica. Agapanthus campanulatus, Boophone disticha, Mondia whitei and Xysmalobium undulatum exhibited antidepressant-like activity in three in vivo models for depression. Amaryllidaceae alkaloids with activity to the serotonin transporter were isolated from Boophone disticha. The alkaloid mesembrine, which act as a serotonin reuptake inhibitor, was isolated from Sceletium tortuosum. Investigations of plants used to treat age-related dementia and debilitative mental disorders lead to the isolation of a number of Amaryllidaceae alkaloids with acetylcholinesterase inhibitory activity from Boophone disticha and Crinum species. Extracts of Mentha aquatica, Gasteria croucheri, Ruta graveolens and Scotia brachypetala inhibited MAO-B. Naringenin was isolated from Mentha aquatica as a MAO inhibitor. Only a small number of the more than 300 southern African plant species reported to treat or affect the CNS have been scientifically evaluated. Very few of the active compounds have been isolated and identified.

HIV infection of the central nervous system: clinical features and neuropathogenesis

Almost 65 million people worldwide have been infected with HIV since it was first identified in the early 1980s. Neurologic disorders associated with HIV type 1 affect between 40% and 70% of infected individuals. The most significant of these disorders include HIV-associated neurocognitive disorder, which comprises HIV-associated dementia, mild neurocognitive disorder, and asymptomatic neurocognitive impairment. Despite the availability of combination antiretroviral therapy, HIV-related central nervous system disorders continue to represent a substantial personal, economic, and societal burden. This review summarizes the clinical manifestations, diagnosis, treatment, and pathogenesis of the primary HIV-associated central nervous system disorders.

Interactions of HIV and methamphetamine: cellular and molecular mechanisms of toxicity potentiation

Methamphetamine (METH) is a highly addictive psychostimulant drug, whose abuse has reached epidemic proportions worldwide. METH use is disproportionally represented among populations at high risks for developing HIV infection or who are already infected with the virus. Psychostimulant abuse has been reported to exacerbate the cognitive deficits and neurodegenerative abnormalities observed in HIV-positive patients. Thus, the purpose of the present paper is to review the clinical and basic observations that METH potentiates the adverse effects of HIV infection. An additional purpose is to provide a synthesis of the cellular and molecular mechanisms that might be responsible for the increased toxicity observed in co-morbid patients. The reviewed data indicate that METH and HIV proteins, including gp120, gp41, Tat, Vpr and Nef, converge on various caspase-dependent death pathways to cause neuronal apoptosis. The role of reactive microgliosis in METH- and in HIV-induced toxicity is also discussed.

Alien hand syndrome in AIDS: Neuropsychological features and physiopathological considerations based on a case report

Alien hand syndrome consists of an autonomous motor activity perceived as an involuntary yet purposeful movement, with a feeling of foreignness of the involved limb, commonly associated with a failure to recognize ownership of the limb in the absence of visual cues. A 41 year old left-handed woman, HIV positive, evolved with loss of control in the left hand. Her left hand presented extravolitional movements, as if having a will of its own, not responding to commands such as opening a door or holding an umbrella, but instead groping unneeded objects. She had talked to her hand and even fought it. In addition, other clinical presentations including recent memory loss, hemineglect and dysphoria were observed. Computed tomography revealed a hypodensity area in the right frontal-parietal region, with midline deviation. Considering clinical and epidemiological data, the diagnosis of Central Nervous System (CNS) toxoplasmosis was reached. No previous reports showing association among AIDS, toxoplasmosis and alien hand syndrome were found.

Diagnosing Epilepsy in the Elderly

Elderly individuals represent the fastest-growing segment of the US population. Seizures are common among elderly persons, and the etiology, clinical presentation, and prognosis of seizure disorders can often differ between elderly patients and younger individuals. However, published information regarding the diagnosis and management of epilepsy in elderly patients is scarce. Because a number of conditions that are common in elderly patients may resemble epilepsy, diagnosis can be challenging. Cardiovascular conditions, migraines, drug effects, infections, metabolic disturbances, sleep disorders, and psychiatric disorders are all associated with signs and symptoms that may often mimic epilepsy. New paradigms must be put into practice to establish an accurate diagnosis in the elderly patient; besides an initial evaluation, the patient history and an electroencephalogram should be obtained. Proper diagnosis is essential for proper treatment in the elderly patient.

Epilepsy in South Africa

Since its first democratic elections in 1994, South Africa has undertaken a massive social reconstruction program that has included major healthcare reform. The state healthcare system aims to provide a unitary service, based on a primary healthcare approach, to the 85% of the population who depend on it. Although the burden of epilepsy is largely unknown, it is likely to be large, with a study of children in a large rural community, for example, demonstrating an active prevalence of 6.7/1000. Common causes of epilepsy are likely to include infectious diseases, such as neurocysticercosis and HIV/AIDS, trauma and alcohol consumption. Limited evidence suggests the existence of a large treatment gap in some areas. The management and treatment of epilepsy are also greatly influenced by cultural attitudes and beliefs, which vary widely. South Africa thus provides a microcosm of issues affecting the management of epilepsy worldwide.

The human immunodeficiency virus-1 protein Tat and its discrete fragments evoke selective release of acetylcholine from human and rat cerebrocortical terminals through species-specific mechanisms

The effect of the human immunodeficiency virus-1 protein Tat was investigated on neurotransmitter release from human and rat cortical nerve endings. Tat failed to affect the release of several neurotransmitters, such as glutamate, GABA, norepinephrine, and others, but it evoked the release of [3H]ACh via increase of cytosolic [Ca2+]. In human nerve terminals, the Tat effect partly depends on Ca2+ entry through voltage-sensitive Ca2+ channels, because Cd2+ halved the Tat-evoked release. Activation of group I metabotropic glutamate receptors (mGluR) and mobilization of Ca2+ from IP3-sensitive intraterminal stores are also involved, because the Tat effect was prevented by mGluR antagonists 2-methyl-6-(phenylethynyl)pyridine hydrochloride and 7-(hydroxyimino)cyclopropa[b]chromen-1a-carboxylate ethyl ester and by the IP3 receptor antagonists heparin and xestospongin C. Furthermore, the group I selective mGlu agonist (RS)-3,5-dihydroxyphenylglycine enhanced [3H]ACh release. In rat nerve terminals, the Tat-evoked release neither depends on external Ca2+ ions entry nor on IP3-mediated mechanisms. Tat seems to cause mobilization of Ca2+ from ryanodine-sensitive internal stores because its effect was prevented by both 8-bromo-cyclic adenosine diphosphate-ribose and dantrolene. The Tat-evoked release from human synaptosomes was mimicked by the peptide sequences Tat 32-62, Tat 49-86, and Tat 41-60. In contrast, the Tat 49-86 and Tat 61-80 fragments, but not the Tat 32-62 fragment, were active in rat synaptosomes. In conclusion, Tat elicits Ca2+-dependent [3H]ACh release by species-specific intraterminal mechanisms by binding via discrete amino acid sequences to different receptive sites on human and rat cholinergic terminals.

The human immunodeficiency virus-1 protein Tat and its discrete fragments evoke selective release of acetylcholine from human and rat cerebrocortical terminals through species-specific mechanisms

The effect of the human immunodeficiency virus-1 protein Tat was investigated on neurotransmitter release from human and rat cortical nerve endings. Tat failed to affect the release of several neurotransmitters, such as glutamate, GABA, norepinephrine, and others, but it evoked the release of [3H]ACh via increase of cytosolic [Ca2+]. In human nerve terminals, the Tat effect partly depends on Ca2+ entry through voltage-sensitive Ca2+ channels, because Cd2+ halved the Tat-evoked release. Activation of group I metabotropic glutamate receptors (mGluR) and mobilization of Ca2+ from IP3-sensitive intraterminal stores are also involved, because the Tat effect was prevented by mGluR antagonists 2-methyl-6-(phenylethynyl)pyridine hydrochloride and 7-(hydroxyimino)cyclopropa[b]chromen-1a-carboxylate ethyl ester and by the IP3 receptor antagonists heparin and xestospongin C. Furthermore, the group I selective mGlu agonist (RS)-3,5-dihydroxyphenylglycine enhanced [3H]ACh release. In rat nerve terminals, the Tat-evoked release neither depends on external Ca2+ ions entry nor on IP3-mediated mechanisms. Tat seems to cause mobilization of Ca2+ from ryanodine-sensitive internal stores because its effect was prevented by both 8-bromo-cyclic adenosine diphosphate-ribose and dantrolene. The Tat-evoked release from human synaptosomes was mimicked by the peptide sequences Tat 32-62, Tat 49-86, and Tat 41-60. In contrast, the Tat 49-86 and Tat 61-80 fragments, but not the Tat 32-62 fragment, were active in rat synaptosomes. In conclusion, Tat elicits Ca2+-dependent [3H]ACh release by species-specific intraterminal mechanisms by binding via discrete amino acid sequences to different receptive sites on human and rat cholinergic terminals.

Profound increase in sensitivity to glutamatergic- but not cholinergic agonist-induced seizures in transgenic mice with astrocyte production of IL-6

Transgenic mice with glial fibrillary acidic protein (GFAP) promoter driven-astrocyte production of the cytokines interleukin-6 (IL-6) and tumor necrosis factor (TNF) were used to determine whether the pre-existing production of these cytokines in vivo might modulate the sensitivity of neurons to excitotoxic agents. Low doses of kainic acid (5 mg/kg) that produced little or no behavioral or electroencephalogram (EEG) alterations in wild type or glial fibrillary acidic protein (GFAP)-TNF animals induced severe tonic-clonic seizures and death in GFAP-IL6 transgenic mice of 2 or 6 months of age. GFAP-IL6 mice were also significantly more sensitive to N-methyl-D-aspartate (NMDA)- but not pilocarpine-induced seizures. Kainic acid uptake in the brain of the GFAP-IL6 mice was higher in the cerebellum but not in other regions. Kainic acid binding in the brain of GFAP-IL6 mice had a similar distribution and density as wild type controls. In the hippocampus of GFAP-IL6 mice that survived low dose kainic acid, there was no change in the extent of either neurodegeneration or astrocytosis. Immunostaining revealed degenerative changes in gamma aminobutyric acid (GABA)- and parvalbumin-positive neurons in the hippocampus of 2-month-old GFAP-IL6 mice which progressed to the loss of these cells at 6 months of age. Thus, GFAP-IL6 but not GFAP-TNF mice showed markedly enhanced sensitivity to glutamatergic- but not cholinergic-induced seizures and lethality. This may relate, in part, to a compromise of inhibitory interneuron function. Therefore, pre-existing IL-6 production and inflammation in the central nervous system (CNS) not only causes spontaneous neurodegeneration but also synergizes with other neurotoxic insults to induce more severe acute functional neurological impairment.

New onset seizures in HIV-infected patients without intracranial mass lesions or meningitis--a clinical, radiological and SPECT scan study

Fifteen HIV-infected patients who presented with new onset seizures (NOS) as the sole neurological manifestation, in whom no cause for the seizure was identifiable, were studied. The patients were mainly female with an average age of 31.3 years. They had generalised new onset seizures with a latency of 1.6 months between the discovery of the HIV positivity and the onset of the seizure. The neurological examinations were normal with no dementia. The electroencephalographic examinations were either normal or there was a generalised epileptic disturbance (GED). The patients have AIDS defining CD4+ T lymphocyte cell counts. There was a high prevalence of pulmonary tuberculosis (PTB) or multiple non-neurological illnesses in our study group. They have normal cerebrospinal fluid (CSF) analysis except for the presence of the HIV virus. All the patients have normal computerised tomogram (CT)/magnetic resonance imaging (MRI) scans of the brain. All the patients studied have abnormal right or left temporal lobe perfusion defects on the SPECT scan studies of the brain. The findings suggest that the new onset seizures in the HIV-infected patients are associated with direct HIV infection. The SPECT scan findings suggest that the HIV virus induce a focal metabolic abnormality or encephalopathy. The new onset seizure is then the manifestation of this abnormality.