Drug-induced toxic epidermal necrolysis. II. Current aspects

Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis--A Comprehensive Review and Guide to Therapy. I. Systemic Disease

The intent of this review is to comprehensively appraise the state of the art with regard to Stevens Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), with particular attention to the ocular surface complications and their management. SJS and TEN represent two ends of a spectrum of immune-mediated, dermatobullous disease, characterized in the acute phase by a febrile illness followed by skin and mucous membrane necrosis and detachment. The widespread keratinocyte death seen in SJS/TEN is rapid and irreversible, and even with early and aggressive intervention, morbidity is severe and mortality not uncommon. We have divided this review into two parts. Part I summarizes the epidemiology and immunopathogenesis of SJS/TEN and discusses systemic therapy and its possible benefits. We hope this review will help the ophthalmologist better understand the mechanisms of disease in SJS/TEN and enhance their care of patients with this complex and often debilitating disease. Part II (April 2016 issue) will focus on ophthalmic manifestations.

Toxic epidermal necrolysis (TEN) Lyell's syndrome

Toxic epidermal necrolysis, a unique rapidly developing mucocutaneous reaction pattern, characterized by sheets of erythema, necrosis and bullous detachment of the epidermis, closely resembling that of scalding of the skin and rapidly fatal, was described by Lyell, and is now recognized as toxic epidermal necrolysis (TEN) Lyell's syndrome. The condition is indistinguishable from staphylococcal scalded skin syndrome (SSSS), and generalized fixed drug eruption. Hence, there has always been controversy as regards terminology. It is well conceived that TEN is equivalent to Stevens-Johnson syndrome (SJS), at its greatest severity. TEN, therefore, is a great challenge and warrants instant attention based on a thorough knowledgeable background covering several related facets including the recent advances in pathogenesis and management strategies. The details contained in the following text should prove very useful in the comprehension of a largely intractable entity.

Clinicopathological features and prognosis of drug rash with eosinophilia and systemic symptoms: a study of 30 cases in Taiwan

BACKGROUND

Drug rash with eosinophilia and systemic symptoms (DRESS), a group of non-blistering severe cutaneous adverse drug reactions (SCADRs), is characterized by skin rash and multiorgan involvement. Details of this reaction have not been reported in the literature so far.

AIM

We investigate clinical and pathological features and prognosis of DRESS and hope this study will provide data concerning this disorder in Taiwan.

METHODS

From January 2001 to June 2006, a total of 30 patients, diagnosed with DRESS, were enrolled and evaluated for demographic characteristics, pathological findings, complications and outcome.

RESULTS

Patient ages ranged from 13 to 78, with an equal sex ratio. The most common offending drug was allopurinol followed by carbamazepine. Pathologic changes observed were lichenoid dermatitis, erythema multiforme, pseudolymphoma and vasculitis. Impairment of liver and renal functions and blood dyscrasia were frequent complications. Active infection or reactivation of HHV-6 was observed in 7 of 11 patients studied serologically. Two patients developed type 1 diabetes mellitus. The mortality rate was 10% (3 of 30).

CONCLUSIONS

DRESS is a heterogeneous group of life-threatening conditions. The leading drug in DRESS in Taiwan is allopurinol. High eosinophil count and multiple underlying diseases are poor prognostic factors in patients with DRESS.

Toxic epidermal necrolysis

Toxic epidermal necrolysis (TEN) is an unpredictable, life-threatening drug reaction associated with a 30% mortality. Massive keratinocyte apoptosis is the hallmark of TEN. Cytotoxic T lymphocytes appear to be the main effector cells and there is experimental evidence for involvement of both the Fas-Fas ligand and perforin/granzyme pathways. Optimal treatment for these patients remains to be clarified. Discontinuation of the offending drug and prompt referral to a burn unit are generally agreed upon steps. Beyond that, however, considerable controversy exists. Evidence both pro and con exists for the use of IVIG, systemic corticosteroid, and other measures. There is also evidence suggesting that combination therapies may be of value. All the clinical data, however, is anecdotal or based on observational or retrospective studies. Definitive answers are not yet available. Given the rarity of TEN and the large number of patients required for a study to be statistically meaningful, placebo controlled trials are logistically difficult to accomplish. The absence of an animal model further hampers research into this condition. This article reviews recent data concerning clinical presentation, pathogenesis and treatment of TEN.

LEARNING OBJECTIVES

At the conclusion of this learning activity, participants should have acquired a more comprehensive knowledge of our current understanding of the classification, clinical presentation, etiology, pathophysiology, prognosis, and treatment of TEN.

Number II Pemphigus vulgaris

Pemphigus is a group of potentially life-threatening autoimmune diseases characterized by cutaneous and/or mucosal blistering. Pemphigus vulgaris (PV), the most common variant, is characterized by circulating IgG antibodies directed against desmoglein 3 (Dsg3), with about half the patients also having Dsg1 autoantibodies. There is a fairly strong genetic background to pemphigus with linkage to HLA class II alleles and ethnic groups such as Ashkenazi Jews and those of Mediterranean and Indian origin, are especially liable. Oral lesions are initially vesiculobullous but readily rupture, new bullae developing as the older ones rupture and ulcerate. Biopsy of perilesional tissue, with histological and immunostaining examination are essential to the diagnosis. Serum autoantibodies to either Dsg1 or Dsg3 are best detected using both normal human skin and monkey oesophagus or by enzyme-linked immunosorbent assay. Before the introduction of corticosteroids, PV was typically fatal mainly from dehydration or secondary systemic infections. Current treatment is largely based on systemic immunosuppression using corticosteroids, with azathioprine or other adjuvants or alternatives but newer therapies with potentially fewer adverse effects, also appear promising.

Pemphigus vulgaris: update on etiopathogenesis, oral manifestations, and management

Pemphigus is a group of potentially life-threatening diseases characterized by cutaneous and mucosal blistering. There is a fairly strong genetic background to pemphigus with linkage to HLA class II alleles. Certain ethnic groups, such as Ashkenazi Jews and those of Mediterranean origin, are especially liable to pemphigus. Pemphigus vulgaris (PV), the most common and important variant, is an autoimmune blistering disease characterized by circulating pathogenic IgG antibodies against desmoglein 3 (Dsg3), about half the patients also having Dsg1 autoantibodies. Oral lesions are initially vesiculobullous but readily rupture, new bullae developing as the older ones rupture and ulcerate. Biopsy of perilesional tissue, with histological and immunostaining examinations, is essential to the diagnosis. Serum autoantibodies to either Dsg1 or Dsg3 are best detected by both normal human skin and monkey esophagus or by enzyme-linked immunosorbent assay (ELISA). Before the introduction of corticosteroids, pemphigus vulgaris was typically fatal mainly from dehydration or secondary systemic infections. Current treatment is largely based on systemic immunosuppression using systemic corticosteroids, with azathioprine, dapsone, methotrexate, cyclophosphamide, and gold as adjuvants or alternatives, but mycophenolate mofetil and intravenous immunoglobulins also appear promising.

Recurrent fatal drug-induced toxic epidermal necrolysis (Lyell's syndrome) after putative beta-lactam cross-reactivity: Case report and scrutiny of antibiotic imputability

OBJECTIVE

A series of antibiotics may be responsible for toxic epidermal necrolysis. We report two successive episodes of toxic epidermal necrolysis in the same patient. Drug imputability criteria designate a cross-reactivity between two antibiotics of different chemical classes but sharing the beta-lactam ring in common.

DESIGN

Descriptive case report and review of the literature.

SETTING

Medical intensive care unit in a university medical center. PATIENT AND MAIN RESULTS: A 75-yr-old woman developed a first episode of toxic epidermal necrolysis (involving 40% of the body surface) after intake of cefotaxime, a third-generation cephalosporin. Perfusions of high-dose immunoglobulins rapidly improved the lesions, followed by partial reepithelialization in 5 days. Sepsis required the administration of meropenem, which is a carbapenem antibiotic. The epidermal destruction immediately recurred, with extension to previously uninvolved skin areas and fatal consequences.

CONCLUSIONS

The beta-lactam ring present in cephalosporins and carbapenems represents the putative chemical structure responsible for the presently reported cross-reactivity to two antibiotics of different classes. Drugs having any chemical similarity to the initial culprit compound should be strictly avoided when possible in the management of toxic epidermal necrolysis.

Trimethoprim/sulfamethoxazole-induced toxic epidermal necrolysis

OBJECTIVE

To report a case of toxic epidermal necrolysis (TEN) associated with trimethoprim/sulfamethoxazole (TMP/SMX).

CASE SUMMARY

A 34-year-old Asian woman developed a severe, desquamating mucocutaneous reaction (TEN) after six days of taking TMP/SMX to treat a presumed urinary tract infection (UTI).

DISCUSSION

TMP/SMX is often recommended as first-line therapy for UTIs, sinusitis, bronchitis, and as prophylaxis and treatment for Pneumocystis carinii pneumonia. TEN is a rare, but severe condition associated with sulfonamide use. This article describes a typical case and offers an opportunity for review of this potentially serious reaction.

CONCLUSIONS

Sulfonamides are often implicated in the majority of drug-induced cases of TEN. This case report illustrates the typical presentation of sulfonamide-induced TEN with a prodrome, characteristic rash, mucous membrane lesions, and systemic involvement. Practitioners should be aware of this rare adverse effect and closely observe patients for cutaneous manifestations or complaints. Any suspected drug should be discontinued if clinical evaluation leads to the suspicion of Stevens-Johnson syndrome or TEN.

Drug-induced Stevens-Johnson syndrome/toxic epidermal necrolysis

Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) is a rare (occurring in approximately 2 to 3 people/million population/year in Europe and the US), life-threatening, intolerance reaction of the skin. It is most often caused by drugs (most commonly sulfonamides, nonsteroidal anti-inflammatory drugs, antimalarials, anticonvulsants, and allopurinol). SJS/TEN is characterized by a macular exanthema ('atypical targets') which focusses on the face, neck, and the central trunk regions. Lesions show rapid confluence, a positive Nikolsky's sign, and quickly result in widespread detachment of the epidermis and erosions. Mucosal, conjunctival, and anogenital mucous membranes are prominently involved. Histopathology shows satellite cell necrosis in the early stages progressing to full thickness necrosis of the epidermis, contrasting with rather inconspicuous inflammatory infiltrates of the dermis. Damage to the skin is thought to be mediated by cytotoxic T lymphocytes and mononuclear cells which induce apoptosis in keratinocytes expressing drug-derived antigens at their surfaces. No guidelines for the treatment of SJS/TEN exist since no controlled clinical trials have ever been performed. The controversy over whether systemic corticosteroids should be used to curtail progression is still unresolved; while many authors agree that corticosteroids do in fact suppress progression, it is obvious that they also greatly enhance the risk of infection, the complication which most frequently leads to a fatal outcome. It appears reasonable to only administer corticosteroids in the phase of progression and to withdraw them as soon as possible, and to add antibacterials for prophylaxis. Recently, in a small series of patients, intravenous immunoglobulins were presumed to be effective by the blockade of lytic Fas ligand-mediated apoptosis in SJS/TEN. However, these results have to be confirmed by large clinical trials. Supportive treatment and monitoring of vital functions is of utmost importance in SJS/TEN, and out-patient treatment is unacceptable. Recovery is usually slow, depending on the extent and severity and the presence of complications, and may take 3 to 6 weeks. Skin lesions heal without scars as a rule, but scarring of mucosal sites is a frequent late complication, potentially leading to blindness, obliteration of the fornices and anogenital strictures. There is no reliable laboratory test to determine the offending drug; diagnosis rests on the patient's history and the empirical risk of drugs to elicit skin SJS/TEN. Provocation tests are not indicated since re-exposure is likely to elicit a new episode of SJS/TEN of increased severity.

Toxic epidermal necrolysis

Toxic epidermal necrolysis (TEN) is a rare, drug-induced, life-threatening syndrome with widespread epidermal loss and mucosal erosions. The classification, pathophysiology, clinical features and treatment are discussed in this review. Prognosis has improved as admission to a burns unit and early treatment of infection has become standard management. The role of corticosteroids in treatment is still controversial.

Determining the true cause of death in a dermatological disaster

Adverse drug reactions that result in patient death warrant special consideration to determine if the outcome was preventable. We report the results of an investigation into the cause of death of a 63 year old male who was thought to have phenytoin-induced toxic epidermal necrolysis (TEN). Most dermatological reactions from drugs are minor and resolve without sequelae once the drug is discontinued. In some cases, reactions are severe and can be life threatening. The patient arrived at the emergency department with extensive exfolative dermatitis. The differential diagnosis included phenytoin-induced TEN, scalded skin syndrome, and phenytoin hypersensitivity. After he was admitted his clinical status deteriorated and he died 13 days after admission. Autopsy findings were significant for necrotizing dermatitis, necrotizing pneumonia, multiple herpetic ulcerations, multisystem organ failure and blood cultures grew Staphylococcus aureus (TSS toxin positive). Findings that indicate a cause of death other than a drug-induced dermatological reaction are presented as well as an overview of the patients' medical history. The differential diagnosis of drug induced skin lesions are also discussed.