Diazepam by continuous intravenous infusion for status epilepticus in anticonvulsant hypersensitivity syndrome

Single centre 20 year survey of antiepileptic drug-induced hypersensitivity reactions

BACKGROUND

Epilepsy is a chronic neurological disease which affects about 1% of the human population. There are 50 million patients in the world suffering from this disease and 2 million new cases per year are observed. The necessary treatment with antiepileptic drugs (AEDs) increases the risk of adverse reactions. In case of 15% of people receiving AEDs, cutaneous reactions, like maculopapular or erythematous pruritic rash, may appear within four weeks of initiating therapy with AEDs.

METHODS

This study involved 300 epileptic patients in the period between September 1989 and September 2009. A cutaneous adverse reaction was defined as a diffuse rash, which had no other obvious reason than a drug effect, and resulted in contacting a physician.

RESULTS

Among 300 epileptic patients of Neurological Practice in Kielce (132 males and 168 females), a skin reaction to at least one AED was found in 30 patients. As much as 95% of the reactions occurred during therapies with carbamazepine, phenytoin, lamotrigine or oxcarbazepine. One of the patients developed Stevens-Johnson syndrome.

CONCLUSION

Some hypersensitivity problems of epileptic patients were obviously related to antiepileptic treatment. Among AEDs, gabapentin, topiramate, levetiracetam, vigabatrin, and phenobarbital were not associated with skin lesions, although the number of patients in the case of the latter was small.

Retrospective analysis of 32 pediatric patients with anticonvulsant hypersensitivity syndrome (ACHSS)

OBJECTIVE

To review 32 pediatric patients with anticonvulsant hypersensitivity syndrome.

DESIGN

Retrospectively, data and photographs were collected on 32 patients who had been diagnosed with anticonvulsant hypersensitivity syndrome.

SETTING

The sections of dermatology at Children's Memorial Hospital in Chicago, Illinois, and Children's Mercy Hospitals and Clinics in Kansas City, Missouri.

MAIN OUTCOME MEASURES

Presentation, implicated medications, laboratory evaluations, complications, treatment and outcome.

RESULTS

The mean age of all patients with anticonvulsant hypersensitivity syndrome (ACHSS) was 8.9 years. The mean duration of anticonvulsant therapy before onset of symptoms was 3 weeks. Phenytoin, carbamazepine, and phenobarbital were the most commonly implicated medications. Lamotrigine, oxcarbamazepine, and primidone were implicated in some of our patients. Fever and rash were seen in all patients, while lymphadenopathy was found in 84.4% of patients. Hematologic abnormalities were seen in 93.8% and hepatic involvement was seen in 90.4% of cases, representing the two most commonly involved systems. Atypical lymphocytosis and eosinophilia was seen in 72% and 56% of patients, respectively. Renal and pulmonary involvement were each seen in 15.6% of cases. Systemic steroids were used in 59.4% of ACHSS patients; 16% of patients received intravenous immunoglobulin. No deaths were reported in our group of pediatric patients.

CONCLUSIONS

The ACHSS is a distinct clinical entity which may occur in pediatric patients treated with anticonvulsants, and may have potentially life-threatening consequences. Involvement of multiple organ systems, including the hematologic, hepatic, renal, and pulmonary systems was common. Treatment varied widely, but ranged from supportive care to systemic corticosteroids.

Cross-sensitivity in a child with anticonvulsant hypersensitivity syndrome

We describe a fulminant picture of anticonvulsant hypersensitivity syndrome (AHS) and the possible role of nitrazepam. A 5-month-old boy developed fever and rash after the use of phenobarbitone. Allergy to phenobarbitone was suspected. Nitrazepam was substituted for seizure control. Over the next few days he progressively collapsed with fever, facial oedema and multi-organ involvement. The diagnosis of AHS was delayed because nitrazepam has not been implicated in the development of cross-sensitivity. AHS is a severe multi-organ reaction to aromatic anti-epileptic drugs. It has been thought to occur as a consequence of pre-existing pharmacogenetic and immunologic abnormalities. Careful selection of anti-epileptic drugs is essential as cross-sensitivity is common. Intermittent benzodiazepines have been recommended in managing breakthrough seizures in AHS. However, the structure of benzodiazepines contains aromatic rings and potential cross-reactivity cannot be totally ignored. Although we do not have direct proof, we believe that nitrazepam prolonged the clinical course.

Anticonvulsant hypersensitivity syndrome: a review

Anticonvulsant hypersensitivity syndrome (AHS), characterised by fever, rash and internal organ involvement, is a rare, but potentially fatal adverse event that occurs most commonly with first-line aromatic anticonvulsants, but can also occur with non-aromatic anticonvulsants such as lamotrigine and valproic acid. AHS can begin anywhere from 1 to 12 weeks after commencement of therapy and has been estimated to occur at a frequency of 1/1000 to 1/10,000 exposures. Its true incidence, however, remains unknown due to under-reporting. The disease has protean manifestations mimicking several other conditions, and the diagnosis is thus difficult. Several hypotheses have been put forward to explain the pathogenesis of AHS. These include accumulation of toxic metabolites, graft versus host disease, antibody production and viral infections. The one based on toxic metabolites has found the greatest acceptance, perhaps due to the fact that it can be proven by an in vitro test; the lymphocyte toxicity assay. Discontinuation of the offending agent with supportive, symptomatic therapy forms the mainstay of management of AHS. In addition, counselling of both the patient and first degree relatives for susceptibility to AHS is an important aspect of management. In the last decade, several new anticonvulsants have been introduced for epilepsy. In addition, for resource-poor countries, inexpensive and effective first-line drugs such as phenytoin and phenobarbitone will continue to remain important treatment options. Thus, the problem of AHS will continue, and attempts should be made to further understand the molecular basis of and individual susceptibility to AHS. Adverse event monitoring programs must also actively seek AHS reports to estimate its true incidence.

Progress in clinical neurosciences: Status epilepticus: a critical review of management options

Although generalized tonic-clonic status epilepticus (SE) is frequently seen, an evidence-based approach to management is limited by a lack of randomized clinical studies. Clinical practice, therefore, relies on a combination of expert recommendations, local hospital guidelines and dogma based on individual preference and past successes. This review explores selected and controversial aspects of SE in adults and provides a critical appraisal of currently recommended management strategies.

Drug-induced hypersensitivity syndrome in pediatric patients

The antiepileptic hypersensitivity syndrome is a severe, multiorgan reaction to oral antiepileptics that manifests as fever, rash, lymphadenopathy, and hepatitis. This same reaction pattern also has been described following administration of a few unrelated medications. We report on 11 patients who had drug-induced hypersensitivity syndrome and were admitted to our pediatric service and review 94 cases of this syndrome in pediatric patients identified from the literature. We undertook this study to summarize the findings and alert clinicians to the severe internal organ involvement that can occur with this syndrome.

Efficacy and mortality in treatment of refractory generalized convulsive status epilepticus in children: a meta-analysis

There is no consensus on the choice of drug treatment for refractory generalized convulsive status epilepticus in children. The objective of this meta-analysis of the published literature was to determine the effects of drug treatments on efficacy (seizure cessation) and mortality in children with this condition, controlling for potential confounding factors. One hundred eleven children, treated with diazepam, midazolam, thiopental, pentobarbital, or isoflurane, met strict inclusion criteria. Diazepam was significantly less efficacious than other treatments (P = .006) stratifying for etiology. Overall mortality was 20% in symptomatic cases and 4% in idiopathic cases (P = .038). Mortality was less frequent in midazolam-treated patients (P = .021) stratifying for etiology. Midazolam appears to be a good choice for initial treatment of refractory generalized convulsive status epilepticus in children, but the attribution of differences in efficacy and mortality solely to drug effect is not possible based on the published literature.

Complications and costs of treatment of refractory generalized convulsive status epilepticus in children

Multiple case series in the literature suggest that benzodiazepines and barbiturates are highly efficacious at stopping seizures. Apparent differences in mortality might not be due solely to drug effect. In this systematic review of the medical literature, we assessed the complications and costs of treatment of refractory status epilepticus in 111 children who met strict inclusion criteria, as part of an effort to provide an evidenced-based recommendation for optimal therapy. All children treated with barbiturates required mechanical ventilation, versus 13% of patients treated with benzodiazepines. Benzodiazepine treatment was associated with pressor use in 3.5% of cases, versus 35% with barbiturate treatment. Midazolam treatment was for the shortest duration and allowed the most rapid return to consciousness. Differences in mean 24-hour drug costs were small compared to savings produced by shorter length of treatment and return to consciousness. Benzodiazepines appear to have higher drug costs but lower complications and overall costs than barbiturates.

Convulsive Status Epilepticus

Generalized convulsive status epilepticus (GCSE) is a medical emergency that must be treated rapidly and aggressively to prevent neuronal damage. Treatment should be initiated with intravenous lorazepam, 0.1 mg/kg, given at a rate of no more than 2 mg/min. If convulsions persist for more than 10 minutes or recur more than 20 minutes after lorazepam therapy is started, then fosphenytoin (20 mg of phenytoin equivalents per kilogram) should be infused at a rate of no more than 150 mg/min. If convulsions still continue, intravenous general anesthesia with pentobarbital, benzodiazepine drip, or propofol should be initiated after respiratory support has been established. All patients with GCSE who do not recover consciousness should be monitored with electroencephalography (EEG), and any residual epileptiform activity on EEG, including periodic epileptiform discharges (PEDs), should be considered evidence of continuing GCSE and treated aggressively.

Acute management of hypersensitivity reactions and seizures

The most crucial step in the management of an antiepileptic drug (AED) hypersensitivity reaction is the recognition of the clinical syndrome and cessation of the presumed offending agent. The severity of the developing reaction will shape the course of treatment because multiple organ systems may become affected. Management of conjunctival involvement and treatment of skin lesions dominate care, with patients whose skin lesions are extensive benefitting from treatment in a structured burn unit. Neutropenia and sepsis are common and potentially fatal complicating factors. The use of steroids remains controversial, as is the utility of immune modulation with other agents such as cyclophosphamide and i.v. immunoglobulin. Acute treatment of seizures should be addressed with i.v. benzodiazepines, given either intermittently or by continuous infusion. Choice of long-term maintenance AEDs should take into consideration the crossreactivity among AEDs that share an arene oxide metabolite.

Anticonvulsant hypersensitivity syndrome

Anticonvulsant hypersensitivity syndrome (AHS) is an uncommon but potentially fatal adverse effect that can occur from exposure to phenytoin, carbamazepine, or phenobarbital. It has diverse clinical features and a variable presentation which results in a delay in making the diagnosis. The syndrome commonly begins within 3 weeks after initiation of an anticonvulsant. Patients typically present with a constellation of fever, usually followed by the development of a rash of variable severity and type, and lymphadenopathy. In patients presenting with these features, the clinician should have a high index of suspicion for AHS.

Status epilepticus and acute repetitive seizures in children, adolescents, and young adults: etiology, outcome, and treatment

Status epilepticus (SE) is one of the most common neurologic emergencies in children, adolescents, and young adults. SE may be due to acute neurologic conditions such as meningitis, encephalitis, or stroke, complicated febrile seizures, intractable epilepsy, degenerative diseases, intoxication, or may be the first manifestation of epilepsy. Initial treatment of convulsive SE is usually with an intravenous benzodiazepine (BZD) [lorazepam (LZP) or diazepam (DZP)], phenobarbital (PB), or phenytoin (PHT). LZP is less likely to cause respiratory depression than DZP and is therefore preferred. Sequelae and risk for recurrence of SE are primarily related to the underlying cause. Refractory SE (RSE) is most often symptomatic of an acute neurologic condition or neurodegenerative disease. Treatment for RSE is difficult, usually requiring intensive support of vital functions. Reported treatments for RSE include very high dose PB, continuous infusions of pentobarbital or BZDs (DZP, midazolam), lidocaine, inhalation anesthesia, and propofol. Outcome is related to underlying cause. Nonconvulsive SE may present as confusion or may mimic psychiatric illness. Response to BZDs is usually rapid but may not be sustained. Rapid initiation of oral or rectal valproate may be useful. Epilepsia partialis continua (EPC) is almost always due to an acute or chronic destructive lesion. Surgical treatment may be the only effective modality in some children with EPC. Acute treatment of breakthrough seizures and clusters of seizures at home with rectal BZDs (usually DZP, 0.2-0.5 mg/kg) may prevent progression to SE in some children and adolescents and reduce the need for visits to emergency facilities.