HLA-B*58:01 Genotyping to Prevent Cases of DRESS and SJS/TEN in East Asians Treated with Allopurinol-A Canadian Missed Opportunity [Formula: see text].

BACKGROUND AND OBJECTIVE: East Asians exposed to the urate-lowering drug allopurinol have a predilection for severe cutaneous drug reactions such as drug-induced hypersensitivity syndrome or drug reaction with eosinophilia and systemic symptoms (DRESS) and Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN). Screening is recommended in patients of East Asian descent for the presence of HLA-B*58:01 prior to allopurinol initiation to avoid these complications. Utilization rates of the HLA-B*58:01 predictive screening test within the Greater Vancouver area, which has a population composed of 40.1% people of East Asian descent, are unknown. MEASURES: We identified cases of DRESS or SJS/TEN due to allopurinol using the Vancouver General Hospital dermatology consult service database. We next compared the frequency in which the HLA-B*58:01 screening test was ordered since 2012 to the estimated frequency of new prescriptions for allopurinol prescribed for the management of gout among the East Asians. RESULTS: We report 5 cases of East Asian patients exposed to allopurinol for management of gout between 2012 and 2016, who developed DRESS (4 patients) or SJS/TEN (1 patient). All were of HLA-B*58:01 genotype, representing preventable cases. The HLA-B*58:01 test was ordered 6 times in 2012, whereas the estimated number of new cases of allopurinol-prescribed gout among patients of East Asian descent during that time period was 13. For 2012, testing was ordered for only 46% of at-risk patients. CONCLUSION: We continue to observe cases of severe cutaneous drug reactions among high-risk individuals due to allopurinol exposure. The HLA-B*58:01 screening test for allopurinol hypersensitivity is underutilized in our geographic area.

Treatment of toxic epidermal necrolysis by a multidisciplinary team. A review of literature and treatment results.

BACKGROUND: Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) are mucocutaneous hypersensitivity reactions, usually to drugs or their metabolites. TEN is the most severe involving greater than 30% of the total body surface area (TBSA). Management of these patients usually benefits from a large multidisciplinary team for both wound and medical management. Treatment of these patients varies between centers and physicians and there is lack of a standardized treatment protocol in the medical literature. OBJECTIVES: To review the literature and complete a retrospective review of patients treated at Vancouver General Hospital over a 11-year period. METHODS: A retrospective chart review of all patients diagnosed with SJS/TEN and treated at Vancouver General Hospital from 2001 to 2011 was completed. Data collected include patient demographics, time to transfer to a burn center, SCORTEN calculation, suspected cause of TEN, %TBSA involved, length of stay in hospital and ICU, medications, dressings, infections/cultures, fluids, mucosal involvement, teams involved, associated complications, morbidity and mortality. Data is reported quantitatively. RESULTS: A total of 67 patients were identified (28 SJS, 21 SJS/TEN overlap, 18 TEN). In SJS/TEN overlap and TEN patients, oral mucosa and trunk were the primary sites involved. SCORTEN calculations were highest in the TEN group. Plastic surgery was consulted in 53% of TEN cases, 52% of SJS/TEN cases and 25% of SJS cases. Patients were admitted to a burn unit in 74% of TEN cases, 57% of TEN/SJS cases and 21% of SJS cases. Time from symptoms to diagnosis and transfer to a burn unit was highest for TEN patients. Time from presentation to diagnosis was highest in SJS/TEN overlap. Triggers were identified in 67-82% of cases. Treatment varied widely. Patients were treated conservatively, with steroids, IVIg, and cyclosporine alone or in combination. Observed mortality was higher than predicted by SCORTEN for patients treated with IVIg and lower for those treated with Cyclosporin. Dressings varied greatly and were often changed throughout a patients stay. Total mortality was 20.9% being the highest in the TEN group (35%). CONCLUSIONS: SJS and TEN are a spectrum of severe mucocutaneous reactions that have unclear treatment recommendations within the literature and within our Level 1 hospital. Information gleaned from this research will help educate physicians involved in the treatment and management of patients with these diagnoses and has resulted in development of treatment guidelines in our hospital.

Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: An Analysis of Triggers and Implications for Improving Prevention.

BACKGROUND: Stevens-Johnson syndrome and toxic epidermal necrolysis are severe mucocutaneous adverse drug reactions characterized by extensive epidermal detachment. The mortality rates have been reported to vary between 1% and 5% for Stevens-Johnson syndrome and 25% and 35% for patients with toxic epidermal necrolysis. Studies have shown that early recognition and prompt withdrawal of the causative agent leads to increased patient survival. METHODS: A retrospective chart review was conducted on 64 patients admitted to Vancouver General Hospital with a diagnosis of Stevens-Johnson syndrome or toxic epidermal necrolysis from 2001 to 2011. The aim of this study was to identify the medications most often implicated in triggering Stevens-Johnson syndrome and toxic epidermal necrolysis, as well as to delineate the timeline of identification and removal of these triggers. RESULTS: A trigger was identified in 75% of cases. Allopurinol was the single most common offending agent (20% of cases). Anticonvulsants and antibiotics were common triggers. The offending agent was often removed at time of hospital admission/diagnosis but not at onset of symptoms. A history of prior culprit drug exposure with previous mucocutaneous adverse reaction was noted in 19% of cases with identified triggers. Asians and Native North Americans had a higher mortality than whites, and Asians more frequently had allopurinol as a trigger. CONCLUSIONS: The onset and high mortality rate of Stevens-Johnson syndrome/toxic epidermal necrolysis may be related to unawareness of the early signs and symptoms of Stevens-Johnson syndrome and toxic epidermal necrolysis, the common drug triggers that cause it, and what investigations (human leukocyte antigen typing in Asians) can be done to prevent it.

Retrospective review of Stevens-Johnson syndrome/toxic epidermal necrolysis treatment comparing intravenous immunoglobulin with cyclosporine.

BACKGROUND: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are mucocutaneous reactions, typically to medications, that are associated with a high patient mortality. Controversy exists over which systemic treatments decrease mortality associated with SJS/TEN. OBJECTIVE: In this study we sought to determine whether intravenous immunoglobulin (IVIg) or cyclosporine use for SJS/TEN results in better patient outcomes. METHODS: We undertook a retrospective chart review of 71 patients admitted between 2001 and 2011 for SJS/TEN at a tertiary care center of which 64 cases were included in the data analysis. Predicted severity-of-illness score for TEN mortality was compared with actual mortality for patients treated with either cyclosporine or IVIg. RESULTS: Our cohort demonstrated a relative mortality benefit to the use of cyclosporine in the treatment of SJS/TEN with a standardized mortality ratio of 0.43, over the use of IVIg with a standardized mortality ratio of 1.43. LIMITATIONS: This is single-center retrospective study. CONCLUSIONS: The use of cyclosporine over IVIg may offer a greater mortality benefit in the treatment of SJS/TEN.