Special populations: The management of seizures in HIV-positive patients

Current epidemiological and etiological characteristics and treatment of seizures or epilepsy in patients with HIV infection

Seizures or epilepsy is one of the common serious complications in patients with advanced human immunodeficiency virus (HIV) infection or diagnosed with immune deficiency syndrome, with higher incidence and prevalence than in the general population. Generalized seizures are the most common type in the patients. Opportunistic infections are a stereotypical predisposing factor for seizures in HIV patients, but a variety of pathogenic factors can also be found in these patients, such as metabolic perturbation and drug-drug interactions. The diagnostic criteria for seizures in these patients are the same as those in the general population. As HIV patients with seizures need to take both antivirals and antiepileptic drugs, the risk of drug-drug interactions is greatly increased, and the side effects of drugs may also become more prominent. At present, most experience in antiepileptic drug usage has come from the general population, and there is still a lack of guidance of antiepileptic drug use in special groups such as the HIV-infected people. Unlike the old-generation drugs that involve metabolisms through CYP450, the first-line antiepileptic drugs usually bypass CYP450, thus having less drug-drug interactions. In this review, we summarize the recent research progress on the above-mentioned widely discussed topics and make a prospect on future research direction.

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.

Frequency of seizures and epilepsy in neurological HIV-infected patients

BACKGROUND

Infection with the human immunodeficiency virus (HIV) is associated both with infections of the central nervous system and with neurological deficits due to direct effects of the neurotropic virus. Seizures and epilepsy are not rare among HIV-infected patients. We investigated the frequency of acute seizures and epilepsy of patients in different stages of HIV infection. In addition, we compared the characteristics of patients who experienced provoked seizures only with those of patients who developed epilepsy.

METHODS

The database of the Department of Neurology, University of Münster, was searched for patients with HIV infection admitted between 1992 and 2004. Their charts were reviewed regarding all available sociodemographic, clinical, neurophysiological, imaging and laboratory data, therapy and outcome. Stage of infection according to the CDC classification and the epileptogenic zone were determined.

RESULTS

Of 831 HIV-infected patients treated in our department, 51 (6.1%) had seizures or epilepsy. Three of the 51 patients (6%) were diagnosed with epilepsy before the onset of the HIV infection. Fourteen patients (27%) only had single or few provoked seizures in the setting of acute cerebral disorders (eight patients), drug withdrawal or sleep withdrawal (two patients), or of unknown cause (four patients). Thirty-four patients (67%) developed epilepsy in the course of their HIV infection. Toxoplasmosis (seven patients), progressive multifocal leukencephalopathy (seven patients) and other acute or subacute cerebral infections (five patients) were the most frequent causes of seizures. EEG data of 38 patients were available. EEG showed generalized and diffuse slowing only in 9 patients, regional slowing in 14 patients and regional slowing and epileptiform discharges in 1 patient. Only 14 of the patients had normal EEG. At the last contact, the majority of the patients (46 patients=90%) were on highly active antiretroviral therapy (HAART). Twenty-seven patients (53%) were on anticonvulsant therapy (gabapentin: 14 patients, carbamazepine: 9 patients, valproate: 2 patients, phenytoin: 1 patient, lamotrigine: 1 patient). Patients with only provoked seizures had no epilepsy risk factors except HIV infection, and were less likely to be infected via intravenous drug abuse.

CONCLUSIONS

Seizures are a relevant neurological symptom during the course of HIV infection. Although in some patients seizures only occur provoked by acute disease processes, the majority of patients with new onset seizures eventually develops epilepsy and require anticonvulsant therapy. Intravenous drug abuse and the presence of non-HIV-associated risk factors for epilepsy seem to be associated with the development of chronic seizures in this patient group.

Treatment of neurosyphilis

In 2001, the incidence of primary and secondary syphilis increased in the United States for the first time in a decade. Increasing rates of early syphilis among men who have sex with men have been reported in many American cities, with similar outbreaks noted in Canada and Europe. In San Francisco, the increase has been particularly sharp and accompanied by an increase in the incidence of neurosyphilis. Early neurosyphilis develops within weeks to years of primary infection and primarily involves the meninges. Syndromes include syphilitic meningitis (often accompanied by cranial neuropathies), meningovascular syphilis (with associated ischemic stroke), or asymptomatic neurosyphilis. Late neurosyphilis occurs years to decades after exposure as cerebral or spinal gummatous disease or the classic parenchymal forms affecting the brain (general paresis or syphilitic encephalitis) or spinal cord and nerve roots (tabes dorsalis). Treponema pallidum, the causative agent, cannot be cultured in vitro, and microscopic techniques are laborious. Thus, diagnosis depends on serologic tests and cerebrospinal fluid (CSF) examination. The suboptimal sensitivity and specificity of these tests complicate diagnosis, particularly among patients coinfected with HIV. CSF examination should be performed to evaluate for neurosyphilis in all patients with positive serum syphilis serology and neurologic, ophthalmic, or tertiary disease, or in those who have failed therapy, and in HIV-infected patients with late latent syphilis or syphilis of unknown duration. Intravenous penicillin G is the recommended treatment for all forms of neurosyphilis and for syphilitic eye disease. An outpatient alternative, if adherence can be assured, is intramuscular benzathine penicillin with oral probenecid. Newer drugs that penetrate CSF, such as ceftriaxone or azithromycin, have not yet been adequately tested for neurosyphilis. Syphilis facilitates transmission of HIV (and vice versa), and thus all patients diagnosed with syphilis should be offered HIV testing.

Seizures in HIV/AIDS: a southern African perspective

South Africa, with a population of 44.8 million, has over 5 million human immunodeficiency virus (HIV)-infected individuals. Over 70% of HIV-infected patients will present with clinically relevant neurologic disease at some stage during the course of their disease. New onset seizures occur in 3-11% of these patients. The mechanism of seizure production in HIV-positive patients includes incidental association, HIV itself, opportunistic infections (OIs), neoplasia, cerebrovascular disease, drug toxicity, and metabolic derangements. In developing countries, OIs constitute the largest group presenting with seizures. Seizure management in HIV-positive patients presents special problems, especially with respect to drug-disease and drug-drug interactions. The older antiepileptic drugs (AEDs) are protein-bound and largely depend on the cytochrome p450 system for their metabolism. The newer AEDs may be safer in patients on antiretroviral drugs. However, they are expensive, an important consideration in developing countries.

Treatment of epilepsy in adults: expert opinion, 2005

RATIONALE

Over the past decade, there has been a proliferation of new therapies for the treatment of epilepsy. Faced with this growing list of options, clinicians must decide what therapy, or combination of therapies, is best for a given individual. Although controlled clinical trials exist for each treatment option, the answer to these questions may remain unclear. In 2000, a survey of expert opinion was done to address questions concerning which treatment options might be best in a number of clinical situations. We surveyed a group of US epileptologists again in 2004 and compared the results of the two surveys.

METHODS

We sent a questionnaire on the treatment of adolescent and adult epilepsy syndromes to a group of opinion leaders in the field of epilepsy. The questions were formatted to simulate real-world clinical situations in the treatment of symptomatic localization related epilepsy (SLRE) and idiopathic generalized epilepsy (IGE). The experts were asked to rate treatment options based on a modified RAND 9-point scale (with "9" most appropriate and "1" least appropriate). Statistical analysis of data was performed as defined by the expert consensus method. The results were used to develop user-friendly recommendations concerning overall treatment strategies and choice of specific medications.

RESULTS

Of the 48 experts to whom the survey was sent, 43 (90%) responded; 29 (67%) of the respondents had also participated in the first survey. For initial monotherapy for IGE (generalized tonic-clonic [GTC], absence, and myoclonic seizures), valproate was rated as treatment of choice. For IGE-GTC seizures, lamotrigine and topiramate were also identified as usually appropriate for initial monotherapy. For IGE-absence seizures, ethosuximide was also a treatment of choice, and lamotrigine was usually appropriate. For SLRE, the experts were again asked to rate treatment options based on seizure type: simple partial seizures (SPS), complex partial seizures (CPS), and secondarily generalized tonic-clonic seizures (SGTC). In SLRE-SPS and SLRE-SGTC, carbamazepine and oxcarbazepine were treatments of choice, with lamotrigine and levetiracetam also usually appropriate. In SLRE-CPS, carbamazepine, lamotrigine. and oxcarbazepine were treatments of choice, while levetiracetam was also usually appropriate. For women who are pregnant or trying to conceive, lamotrigine was treatment of choice for both syndrome types. In the elderly, whether medically stable or ill, the treatment of choice was lamotrigine, while levetiracetam was also usually appropriate (along with gabapentin for persons with comorbid medical illness). In persons with HIV and epilepsy, lamotrigine and levetiracetam were usually appropriate. In people with both epilepsy syndromes who have depression, lamotrigine was treatment of choice. In a person with seizures and renal disease, lamotrigine was usually appropriate for both syndromes, with valproate also usually appropriate for IGE. In patients with hepatic disease, levetiracetam and lamotrigine were usually appropriate for IGE; in SLRE, levetiracetam was treatment of choice, with gabapentin also usually appropriate.

CONCLUSIONS

Although the panel of experts reached consensus on many treatment options, there are limitations to these types of data. Despite this, the expert consensus method concisely summarizes expert opinion, and this opinion may be helpful in situations in which the medical literature is scant or lacking. The information in this report should be evaluated in conjunction with evidence-based findings.