Medication use and the risk of Stevens-Johnson syndrome or toxic epidermal necrolysis

Evaluation of case reports of aplastic anemia among patients treated with felbamate

PURPOSE

Felbamate (FBM) is a new antiepileptic drug (AED) that is often effective in seizure disorders refractory to other treatments; its use has been greatly restricted after cases of aplastic anemia were reported. To elucidate the putative association between FBM and aplastic anemia, we made a detailed evaluation of the first 31 reports.

METHODS

Hematologic review according to the criteria of the International Agranulocytosis and Aplastic Anemia Study (IAAAS) confirmed 23 cases (74%) as aplastic anemia; FBM was judged to be the only plausible cause for three; confounding (mostly by other drugs) was considered possible, but FBM remained the most likely cause for 11; and there was at least one other plausible cause for 9.

RESULTS

Using a denominator from sales data of 110,000 persons exposed and a numerator of the cases for which FBM was considered the only plausible cause, we established a lower limit of incidence of 27 cases of aplastic anemia per million users as compared with the general population rate of 2.0 per million per year. With all confirmed cases used as the numerator, the upper limit of incidence was 209 per million. The 'most probable" incidence was estimated to be 127 per million.

CONCLUSIONS

Intensive, systematic investigation can maximize the utility of case reports for assessing risks of newly released drugs. The present evaluation confirmed an association between FBM and aplastic anemia; however, confounding was significant for most cases and there was a tenfold range in the "best case" and "worst case" incidence estimates among users.

An assessment of antigenic potential of beta-lactam antibiotics, low molecular weight drugs, using guinea pig models

Allergic reactions are among the common adverse effects in humans. However, it is widely assumed that there are practically no reliable animal models for preclinical tests of low-molecular weight drugs that are available to predict such reactions. This study was designed to compare the detecting ability of test methods for antigenic potential of eight beta-lactam antibiotics with which allergic outcome has been reported in humans. The tests included active systemic anaphylaxis (ASA), delayed type skin reaction (DSR), maximization test (GPMT) in guinea pigs sensitized with antibiotics emulsified with Freund's complete adjuvant, passive cutaneous anaphylaxis (PCA) and enzyme-linked immunosorbent assay (ELISA) as serological tests. PCA and ELISA though using protein-conjugates as detecting antigens, especially ELISA, showed positive reactions with relatively high incidence. On the other hand, GPMT was the most sensitive method to detect antigenic potential of antibiotics despite the use of antibiotics alone for sensitizing and challenging phases. It is suggested that GPMT can be considered the most reliable method in preclinical testing.

Stevens-Johnson syndrome and toxic epidermal necrolysis are severity variants of the same disease which differs from erythema multiforme

A new classification, based on the pattern and distribution of cutaneous lesions, separates erythema multiforme major from Stevens-Johnson syndrome. A retrospective re-classification of 76 cases supported the validity of that separation by demonstrating differing causes and pathology. Another prospective international case-control study found differing demographic characteristics and risk factors between erythema multiforme major on the one hand and Stevens-Johnson syndrome or toxic epidermal necrolysis on the other. Erythema multiforme major was mainly related to Herpes virus infection, while Stevens-Johnson syndrome and toxic epidermal necrolysis were associated with drug reactions.

Phenolphthalein-induced toxic epidermal necrolysis

OBJECTIVE

To report a case of phenolphthalein-induced toxic epidermal necrolysis (TEN) in a patient maintained on several other medications more commonly known to be associated with TEN.

CASE SUMMARY

A 78-year-old white man presented with intractable lower back pain and constipation. On day 1 of admission, the patient exhibited a diffuse urticarial rash over his trunk and extremities. History revealed that the patient had taken a combination phenolphthalein/docusate sodium (Correctol) over-the-counter laxative 1 day prior to admission. He had a similar urticarial rash 1.5 years earlier with this product and was instructed not to use it. A biopsy was performed and evidence from light microscopic analysis of the tissue led to a diagnosis of TEN. Furosemide, spironolactone, allopurinol, and hydroxyurea were considered possible causes of the reaction and were discontinued. Despite this, the lesions worsened in severity. The patient subsequently responded well to intravenous antibiotics, intravenous corticosteroids, and local wound care. Furosemide, spironolactone, hydroxyurea, allopurinol, and docusate were all reintroduced without reactivation of the lesions.

DISCUSSION

Phenolphthalein is the active ingredient in several over-the-counter laxative preparations and has only rarely been reported to cause TEN. (It is no longer contained in Correctol.) To our knowledge, this case report represents only the third description of laxative-induced TEN. Although this patient had been exposed to several other medications more commonly associated with TEN, his long-term tolerance of and uneventful rechallenge with these medications exclude them as potential catalysts to this drug reaction. The patient's previous rash and the temporal relation of this event and the ingestion of phenolphthalein, as well as the similarity of this case to other reports, point to phenolphthalein as the cause of TEN in this patient.

CONCLUSIONS

TEN is a rare disorder that can be fatal in up to 30% of patients. Clinicians should include phenolphthalein in their list of possible causes of drug-induced TEN. A careful and complete medication history can help avoid unnecessary discontinuation of clinically important medications and inadvertent rechallenge with the causative agent.

Toxic epidermal necrolysis possibly linked to hyperacute graft-versus-host disease after allogeneic bone marrow transplantation

Toxic epidermal necrolysis (TEN) is a severe blistering skin disease of high mortality. TEN may occur after bone marrow transplantation (BMT). In such cases, TEN have been attributed to graft-versus-host disease (GVHD) or an adverse drug reaction. It is very difficult to distinguish the causes of TEN after BMT. We report a 21-year-old Japanese man who developed TEN eight days after BMT, evaluate the differential diagnosis of hyperacute GVHD and an adverse drug reaction, and deduce that hyperacute GVHD was the more likely pathogenesis of TEN in this patient.

Stevens-Johnson syndrome associated with carvedilol therapy

Stevens-Johnson syndrome, related to carvedilol use, has not been previously reported as a serious adverse experience requiring hospitalization. We report this reaction in a 71-year-old man with stable ischemic cardiomyopathy.

Safety of long-term lamotrigine in epilepsy

PURPOSE

To examine the safety of lamotrigine (LTG) used in general practice to treat epilepsy.

METHODS

Information was collected on 11,316 patients who were included in a noninterventional observational cohort study conducted by means of Prescription-Event Monitoring (PEM). A follow-up study provided information on the first 3,994 patients who had taken LTG for > or = 6 months. Incidence density (ID) measurements were used to rank the frequency of the reported events.

RESULTS

Rash was the most frequently reported nonepileptiform event (ID, 19.7/1,000 patient-months) in the first month of treatment and resulted in LTG being stopped in 2% of the 11,316 patients. Rash was reported more frequently among children aged 2-12 years (ID, 29.4/1,000 patient-months) than adults. Other events associated with the use of LTG included headache, drowsiness, nausea, vomiting, malaise, and lassitude. Rare serious events possibly associated with LTG included 12 cases reported as Stevens-Johnson syndrome, four cases of neutropenia, three cases of thrombocytopenia, and two cases of disseminated intravascular coagulation. There were also individual cases of leucopenia, a meningitic reaction, acute renal failure, hepatotoxicity, and a "lupus-like" reaction possibly associated with the drug. No foetal abnormalities were specifically associated with the use of the drug in pregnancy. No death was attributed to LTG.

CONCLUSIONS

Patients had severe epilepsy, inadequately controlled by other antiepileptic agents. The results of these two studies suggest that LTG is acceptably safe when used for the treatment of refractory epilepsy.

Suspected lamotrigine-induced toxic epidermal necrolysis

OBJECTIVE

To describe a patient who developed toxic epidermal necrolysis (TEN) possibly secondary to lamotrigine use.

CASE SUMMARY

A 74-year-old white man with a history of probable complex partial seizures was admitted to the neurology service for a prolonged postictal state. His antiepileptic regimen was changed while he was in the hospital to include lamotrigine. After 19 days of hospitalization and 14 days of lamotrigine therapy, the patient became febrile. The next day he developed a rash which progressed within 4 days to TEN, diagnosed by skin biopsy. All suspected drugs were discontinued, including lamotrigine. The patient was treated with hydrotherapy in the burn unit. His symptoms improved and he was discharged from the hospital 26 days after the rash developed.

DISCUSSION

During lamotrigine's premarketing clinical trials, the manufacturer reported several cases of Stevens-Johnson syndrome and TEN. There are several published case reports of lamotrigine-induced severe skin reactions. All of these reports included patients being treated with both valproic acid and lamotrigine. Our patient was exposed to phenytoin, carbamazepine, clindamycin, and lamotrigine, but not valproic acid. The patient reported prior use of phenytoin with no skin rash. Carbamazepine was the antiepileptic drug the patient was maintained on prior to his hospital admission, and the symptoms of TEN resolved while he was still receiving carbamazepine. The patient received only two doses of clindamycin, which makes this agent an unlikely cause of TEN.

CONCLUSIONS

Because of the temporal relationship of the onset of the patient's rash and several drugs that are known to cause severe rashes, it is not certain which drug was the definite culprit. However, based on the evidence from the literature, lamotrigine appears to be the causative agent.

Pulmonary complications in toxic epidermal necrolysis: a prospective clinical study

OBJECTIVE

To evaluate the incidence, clinical features, and prognosis of pulmonary complications associated with toxic epidermal necrolysis

DESIGN

Prospective study.

SETTING

Dermatology intensive care unit in Mondor Hospital, France.

PATIENTS

41 consecutive patients.

INTERVENTIONS

On admission, then daily, respiratory evaluation was based on clinical examination, chest X-ray, and arterial blood gas analysis. When clinical symptoms, X-ray abnormalities, or hypoxemia [partial pressure of oxygen (PO2) < 80 mm Hg] were present, fiberoptic bronchoscopy was performed.

RESULTS

10 patients presented early manifestations: dyspnea (n = 10), bronchial hypersecretion (n = 7), marked hypoxemia (n = 10) (PO2 = 59 +/- 8 mm Hg). Chest X-ray was normal (n = 8) or showed interstitial infiltrates (n = 2). In these 10 patients, fiberoptic bronchoscopy demonstrated sloughing of bronchial epithelium in proximal airways. Delayed pulmonary complications occurred in 6 of these 10 patients from day 7 to day 15: pulmonary edema (n = 2), atelectasis (n = 1), bacterial pneumonitis (n = 4). Mechanical ventilation was required in 9 patients. A fatal outcome occurred in 7 patients. Seven patients did not develop early pulmonary manifestations (PO2 on admission 87 +/- 6 mm Hg) but only delayed pulmonary symptoms related to atelectasis (n = 1), pulmonary edema (n = 4), and bacterial pneumonitis (n = 3); bronchial epithelial detachment was not observed. None of them required mechanical ventilation and all recovered with appropriate therapy.

CONCLUSIONS

"Specific" involvement of bronchial epithelium was noted in 27% of cases and must be suspected when dyspnea, bronchial hypersecretion, normal chest X-ray, and marked hypoxemia are present during the early stages of toxic epidermal necrosis. Bronchial injury seems to indicate a poor prognosis, as mechanical ventilation was required for most of these patients and was associated with a high mortality.

Epidemiology of drug-induced severe skin reactions

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe, sometimes life-threatening skin reactions that are often drug-induced. Unfortunately, the definitions and nomenclature of these severe skin reactions have been confusing, and thus various publications on this issue can hardly be compared. After several attempts have been made to clarify this situation, a consensus definition published in 1993 suggests the differentiation between erythema exsudativum multiforme majus (EEMM) and SJS, as well as an overlap group of SJS and TEN, whereas TEN with maculae is the most severe type of skin reaction with more than 30% of skin detachment related to the body surface area (BSA). This classification was applied to cases of severe skin reactions in several large studies that have been undertaken within the last few years and published recently. The incidence of SJS, SJS/TEN overlap and TEN has been estimated to be approximately 1.89 cases per one million people per year. Although SJS and TEN occur very rarely, a mortality rate of more than 40% can be calculated for patients suffering from TEN. One may conclude that mortality increases with age and the amount of skin detachment related to the BSA. A number of drugs have been reported to induce severe skin reactions, eg, anti-infective sulfonamides, antibiotics, anticonvulsants and nonsteroidal anti-inflammatory drugs. For risk evaluation for certain drugs or drug groups population-based data as ascertained by the German registry of severe skin reactions, and prescription data in defined daily doses can be used. In addition, risk evaluation is possible by performing a case-control study as it has been undertaken within different European countries. As long as the pathogenesis of drug-induced severe skin reactions is not known, and specific screening methods to identify susceptible individuals do not exist, the epidemiological approach will remain the only possibility for risk estimation.

Advances in toxic epidermal necrolysis

On the basis of the clinicopathologic and causative characteristics, one can separate an erythema multiformis spectrum from a toxic epidermal necrolysis (TEN)-Stevens Johnson syndrome which is a drug induced disease. Despite a well-known clinical aspect, several cutaneous diseases may be mistaken for TEN. Responsible drugs are sulfonamides anticonvulsants, and nonsteroidal antiinflammatory drugs--patients infected with HIV are at a higher risk of developing TEN. Pathogenesis includes abnormal drug metabolism and cell mediated immune keratinocyte apoptosis. Treatment relies on symptomatic management and so-called specific treatments including steroids are probably harmful.

Immunologic mechanisms of cutaneous drug reactions

Idiosyncratic reactions (type B) are a major complication of drug therapy, because they are related to both the drug and to individual factors in the host. In comparison with other organs, the skin is quite frequently a target of allergic reactions, which are mainly elicited by small molecular weight compounds. This is the case in allergic contact dermatitis as well as in drug allergic reactions. In contrast to allergic contact dermatitis however, drug-induced hypersensitivity reactions of the skin have enormous variability with regard to their pathophysiological pathways, clinical signs of symptoms, severity, and the drugs which can elicit these reactions. Allergic reactions are mediated either by specific antibodies or a cellular immunocompetent immune response. About 25% to 30% of type B reactions are estimated to be allergic drug reactions, which are classified by the latency period between the ingestion of the responsible allergen and the onset of clinical symptoms. Studying the mechanisms of these hypersensitivity reactions improves our understanding of these diseases in general, and shows the importance of the skin as a signaling organ in these reactions.

Nonrenal toxicities of acetaminophen, aspirin, and nonsteroidal anti-inflammatory agents

Approximately 2% of the United States population consumes an analgesic, antipyretic, or nonsteroidal antiinflammatory drug (NSAID) each day. Aspirin and acetaminophen have been available to the public without a prescription (over-the-counter) for decades, while most NSAIDs are still only available with a prescription from a physician. The recent trend of switching NSAIDs from prescription to over-the-counter status may be perceived by some as an indication of their inherent safety. However, all these agents have been associated with a unique but overlapping safety profile. In fact, significant adverse events (AEs) on multiple organ systems, including the kidney and gastrointestinal tract, have been reported with most of these agents. In this review, the incidence of the nonrenal AEs of aspirin, acetaminophen, and selected NSAIDs are tabulated. The strengths of the causative associations are highlighted, the relative risks for the gastrointestinal and cardiovascular AEs are discussed, and the relationship to patient risk factors and drug characteristics, such as dose and half-life, are reviewed. The selection of the optimal agent for an individual patient depends on the balance between the desired pharmacodynamic response, the patient's pharmacotherapy history, and the degree of AE risk one is willing to accept. Therapy should be initiated in all settings with the lowest possible dosage since the incidence of the major AEs is dose related.