Seizures in HIV/AIDS: a southern African perspective

Late diagnosis of human immunodeficiency virus infection is linked to higher rates of epilepsy in children in the Eastern Cape of South Africa

BACKGROUND

Human immunodeficiency virus (HIV)-positive children may present with a wide range of neurological disorders. Among these, epilepsy is of key concern because of its lifelong impact and potential for damage to the central nervous system (CNS). Few studies in developing regions have investigated the prevalence and aetiology of epilepsy in HIV-infected children as a key population.

OBJECTIVES

We describe the prevalence of epilepsy, associated neurological disabilities, immunological status, clinical stage and history of CNS infection at epilepsy diagnosis in a cohort of HIV-infected children receiving antiretroviral therapy (ART) in the Eastern Cape of South Africa.

METHODS

We conducted a retrospective study (2004-2014) at two major referral sites for HIV-infected children diagnosed with epilepsy aged 0-16 years. Eligible subjects were extracted from the electronic medicine bridging access to care in excellence (EMBRACE) Paediatric Cohort using the Paediatric ART Data Management Tool (PADMT). Fixed data fields were interrogated for exposures to antiepileptic drugs. Unstructured 'comments' fields were searched for the terms: epilepsy, seizures, fits and szs, as well as abbreviated versions of common antiepileptic drug names. Eligible subject folders were then retrieved to validate the digital data.

RESULTS

From 2139 children enrolled in the two sites, 53 children were diagnosed with epilepsy (2.48%). In these, the median CD4 count was 591 cells/mm3, and the mean viral load was 4.9 log copies/mL, with undetectable viral loads in only seven children (14.0%). World Health Organization (WHO) clinical HIV stage was available for 46 patients of the sample, with 3, 6, 26 and 11 children graded at stages 1, 2, 3 and 4, respectively. Forty percent children had a history of CNS infection prior to the epilepsy diagnosis, and 55% children were reported to have school problems.

CONCLUSIONS

In this descriptive study, the prevalence of epilepsy among children with HIV was 2.48%, mostly diagnosed in advanced HIV-disease stages. Our findings support the usefulness of early detection and initiation of ART in HIV-infected children in order to reduce the risk of epilepsy. In addition, our study demonstrates that novel techniques are effective in accessing cohort-level data that allow interrogation of both structured and unstructured clinical data.

Exposure to multiple parasites is associated with the prevalence of active convulsive epilepsy in sub-Saharan Africa

Background

Epilepsy is common in developing countries, and it is often associated with parasitic infections. We investigated the relationship between exposure to parasitic infections, particularly multiple infections and active convulsive epilepsy (ACE), in five sites across sub-Saharan Africa.

Methods and Findings

A case-control design that matched on age and location was used. Blood samples were collected from 986 prevalent cases and 1,313 age-matched community controls and tested for presence of antibodies to Onchocerca volvulus, Toxocara canis, Toxoplasma gondii, Plasmodium falciparum, Taenia solium and HIV. Exposure (seropositivity) to Onchocerca volvulus (OR = 1.98; 95%CI: 1.52–2.58, p<0.001), Toxocara canis (OR = 1.52; 95%CI: 1.23–1.87, p<0.001), Toxoplasma gondii (OR = 1.28; 95%CI: 1.04–1.56, p = 0.018) and higher antibody levels (top tertile) to Toxocara canis (OR = 1.70; 95%CI: 1.30–2.24, p<0.001) were associated with an increased prevalence of ACE. Exposure to multiple infections was common (73.8% of cases and 65.5% of controls had been exposed to two or more infections), and for T. gondii and O. volvulus co-infection, their combined effect on the prevalence of ACE, as determined by the relative excess risk due to interaction (RERI), was more than additive (T. gondii and O. volvulus, RERI = 1.19). The prevalence of T. solium antibodies was low (2.8% of cases and 2.2% of controls) and was not associated with ACE in the study areas.

Conclusion

This study investigates how the degree of exposure to parasites and multiple parasitic infections are associated with ACE and may explain conflicting results obtained when only seropositivity is considered. The findings from this study should be further validated.

The prevalence of epilepsy is greater in developing countries compared to developed countries, and parasitic infestations are thought to contribute to this increased burden. We conducted a case-control study across five sites in sub-Saharan Africa to investigate the relationship between epilepsy and exposure to parasitic infections, and the association between epilepsy and multiple co-incidental infections. Exposure to Onchocerca volvulus, Toxocara canis and Toxoplasma gondii as well as high antibody levels (top tertile) to Toxocara canis was positively associated with the prevalence of active convulsive epilepsy (ACE). Multiple co-incidental parasitic infections were common, and the combined effect of T. gondii and O. volvulus co-infection on ACE was greater than the sum of the individual effects. The contribution of each of these parasitic infections on the burden of epilepsy in sub-Saharan Africa should be explored.

Prevalence of seizures in children infected with human immunodeficiency virus

A retrospective study of 354 human immunodeficiency virus (HIV)-infected patients identified a subgroup of 27 children with seizures (7.6%, 95% confidence interval: 5.1%-10.9%). Of the total group, 13% (n = 46) had identifiable neurologic deficits and 30% (n = 107) had developmental delay. Both observations were significantly more frequent in the subgroup of patients with seizures (P < .001). The median age of patients with seizures was 20 months (range, 8-87 months) and the median baseline CD4 percentage was 13.5% (interquartile range, 8%-23%). Seizures were treated with sodium valproate (n = 11), phenobarbital (n = 3), diazepam (n = 2), lamotrigine (n = 1), and carbamazepine (n = 1). Combination therapy was required for 5 children. Suboptimal valproic acid levels were recorded for 3 patients. When resources are available, antiepileptic drug level monitoring is advised for children who require both antiepileptic and antiretroviral medications to facilitate optimal seizure management.

Child neurology practice and neurological disorders in East Africa

Neurological disorders, including neurodevelopmental disorders, have been identified by the World Health Organization (WHO) as one of the greatest threats to global public health. It is generally believed that these conditions are more prevalent in the developing than the developed world because of multiple known risk factors such as infections, malnutrition, and limited resources for obstetric and neonatal management. In East Africa, few investigations have been conducted to obtain data on the magnitude and description of neurological disorders among children, and the practice of child neurology is faced with challenges cutting across areas of health personnel, patient diagnosis, management, and rehabilitation. This article reviews the burden, types, and causes of neurological disorders in the East African region. The challenges and successes in the practice of child neurology and recommendations for the future are discussed.

Effect of prescribed minimum benefits on the prevalence of possible drug-drug interactions of antiretroviral agents in a section of the private health care sector in South Africa: a 2 year comparative study

Objective

The aim of this study was to determine the impact of prescribed minimum benefits (PMBs) after implementation, on the prevalence of possible drug-drug interactions (DDIs) between antiretrovirals (ARVs) themselves and other drugs on prescriptions claimed in a section of the private health care sector in South Africa.

Setting

A section of the private health care sector in South Africa.

Method

A comparative, retrospective drug-utilisation study was performed using 2004 and 2005 data from a medicine claims database. Possible DDIs found were classified according to Tatro (2005).

Key findings

The data consisted of 43 482 ARV prescriptions claimed during 2004 and 51 613 for 2005. A total of 5 305 882 and 3 606 992 medicine items were claimed during 2004 and 2005 respectively, of which 1.92% were ARVs for 2004 and 3.38% for 2005. Of 18 035 DDIs identified, 83.89% were between ARVs and other medications, and 16.11% were between ARVs themselves for 2004. Of 25 130 DDIs identified for 2005, 92.59% were between ARVs and other medications, and 7.41% were between ARVs themselves.

Conclusions

The decrease in DDIs between ARVs alone for 2005 as compared to 2004 could indicate a possible impact of PMBs on HIV/AIDS, as a chronic disease in which management programmes were introduced to ensure the appropriateness and effectiveness of drugs in HIV/AIDS. It is therefore recommended that further investigations be done on the management of the most important DDIs between ARVs alone and other drugs prescribed on the same prescription.