Economic Evaluation of HLA-B*15:02 Genotyping for Asian Australian Patients With Epilepsy.

Importance: The HLA-B*15:02 allele has been associated with an increased risk of carbamazepine-induced Stevens-Johnson syndrome and toxic epidermal necrolysis in specific Asian populations (including Han Chinese, Malaysian, Thai, and Vietnamese individuals). While HLA-B*15:02 genotype testing in Asian populations is recommended by several international prescribing guidelines, it is not subsidized by the Medicare Benefits Schedule in Australia. Objective: To evaluate the cost-effectiveness of HLA-B*15:02 genotyping in Asian Australian patients with epilepsy. Design, Setting, and Participants: A model with components of decision analysis and Markov simulation was developed to simulate clinical trajectories of adult Asian Australian patients with newly diagnosed epilepsy being considered for carbamazepine treatment. Cost-effectiveness and cost-utility analyses over a lifetime time horizon were conducted from the perspective of the Australian health care sector. The study was conducted in May 2023 and data analysis was performed from August 2023 to November 2023. Intervention: No HLA-B*15:02 genotyping and the empirical initiation of treatment with carbamazepine vs HLA-B*15:02 genotyping and the initiation of treatment with valproate in allele carriers. Main Outcomes and Measures: Life-years (LYs), quality-adjusted life-years (QALYs), and costs in 2023 Australian dollars (A$); incremental cost-effectiveness ratios. Results: HLA-B*15:02 screening was associated with an additional mean cost of A$114 (95% CI, -A$83 to A$374; US$76; 95% CI, -US$55 to US$248) and a reduction in 0.0152 LYs (95% CI, 0.0045 to 0.0287 LYs) but improvement by 0.00722 QALYs (95% CI, -0.0247 to -0.01210) compared with no screening, resulting in an incremental cost-effectiveness ratio of A$15 839 per QALY gained (US$10 523 per QALY). Therefore, universal genotyping for Asian Australian individuals was cost-effective compared with current standards of practice at the A$50 000 per QALY willingness-to-pay threshold. Sensitivity analyses demonstrated that the intervention remained cost-effective across a range of costs, utilities, transition probabilities, and willingness-to-pay thresholds. At the A$50 000 per QALY willingness-to-pay threshold, universal screening was the preferred strategy in 88.60% of simulations. Conclusions and Relevance: The results of this economic evaluation suggest that HLA-B*15:02 screening represents a cost-effective choice for Asian Australian patients with epilepsy who are being considered for treatment with carbamazepine.

Human Leukocyte Antigen Gene Testing and Carbamazepine-Induced Toxic Epidermal Necrolysis: A Study of Pediatric Practice.

BACKGROUND: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening drug-induced dermatologic conditions. SJS/TEN occurs in 1-10 per 10 000 patients taking carbamazepine (CBZ) (Pratt VM, McLeod HL, Rubinstein WS et al. Medical Genetics Summaries. National Center for Biotechnology Information US; 2018: 1-527). The development of SJS/TEN is associated with variable drug metabolism and presence of an at-risk HLA haplotype. HLA-B*15:02 and HLA-A*31:01 haplotypes can produce a hyperimmune response in the setting of CBZ use in patients of Asian and European descent, respectively (Schneider JA, Cohen PR. Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: A concise review with a comprehensive summary of therapeutic interventions emphasizing supportive measures. Adv Ther. 2017; 34:1235-1244). OBJECTIVE: The US Food and Drug Administration (FDA) and the Canadian pharmacogenomics Network for Drug Safety (CPNDS) recommend that patients with high-risk ethnic backgrounds should be genetic tested before initiating CBZ (Sukasem C, Chaichan C, Nakkrut T et al. Association between HLA-B Alleles and Carbamazepine-induced maculopapular exanthema and severe cutaneous reactions in Thai patients. Journal of Immunology Research. 2018; 1-11).We sought out to assess the awareness of this in prescribing practitioners and their standard of practice. METHODS: We created a 15-question survey and distributed to pediatric neurologists and pediatricians at the University of Alberta. We hypothesized that there was a discordance between the standard of practice and the recommendation by the FDA and CPNDS. RESULTS: The survey results indicated a lack of awareness of the at-risk ethnicities for CBZ-induced SJS/TEN. HLA gene testing was rarely done prior to initiation of CBZ in high-risk patients. In addition, there was a lack of awareness for standard of care for genetic testing in Canada and worldwide. CONCLUSIONS: Our results demonstrate an evident gap between current prescriber practices and existing FDA and CPNDS recommendations to screen for HLA genotypes. We hope that this study captures the realistic potential to improve patient outcomes.

Osimertinib-Associated Toxic Epidermal Necrolysis in a Lung Cancer Patient Harboring an EGFR Mutation-A Case Report and a Review of the Literature.

Toxic epidermal necrolysis (TEN) and Stevens-Johnson syndrome (SJS) are life-threatening dermatologic adverse events in the same category, caused by a delayed-type drug hypersensitivity reaction. Although skin toxicity is common during treatment with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), osimertinib-associated TEN is quite rare-thus far, only one report has been published from China. We report a case of an 80-year-old Japanese woman with lung adenocarcinoma harboring an EGFR-sensitizing mutation who was treated with osimertinib as the first-line treatment. Forty-six days after osimertinib induction, diffuse erythematous rash rapidly spread over the patient's trunk along with vesicles and purpuric macules; furthermore, she developed targetoid erythema on the face. Despite osimertinib discontinuation and corticosteroid treatment, diffuse erythema with Nikolsky's sign, general epidermal detachment, erosion and loose blisters developed over her entire body including the face. Based on her symptoms, TEN was diagnosed and thus, intravenous immunoglobulin was immediately administered for 4 days. The treatment ameliorated TEN-associated skin toxicity and caused epithelialization. Reports on osimertinib-associated SJS/TEN are scarce and only one report each on SJS and TEN from China is available. This is the first report of osimertinib-associated TEN from Japan. Cases of EGFR-TKI-associated SJS/TEN have been reported predominantly from Asian countries, suggesting ethnicity and genetic linkage play a role in the underlying mechanism.

The association of HLA B*15:02 allele and Stevens-Johnson syndrome/toxic epidermal necrolysis induced by aromatic anticonvulsant drugs in a South Indian population.

BACKGROUND: The presence of HLA-B*15:02 allele is considered a risk factor for development of Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) in patients taking aromatic anticonvulsant drugs like carbamazepine and phenytoin. The genetic association is ethnicity specific. Testing for HLA-B*15:02 allele is suggested as a prerequisite before starting carbamazepine in certain ethnic groups. There are only a few/no studies from south India on HLA association of SJS/TEN. AIMS: To identify any association between HLA-B*15:02 allele and SJS/TEN induced by carbamazepine/phenytoin among native population. METHODS (INCLUDING SETTINGS, DESIGN, AND STATISTICAL ANALYSIS USED): A case-control study done in a tertiary care center at Kottayam in Kerala state of south India. Cases were 12 native patients who developed SJS/TEN owing to aromatic anticonvulsant drugs (phenytoin - 8; carbamazepine - 4), and controls were 11 persons tolerant to these drugs from unrelated families of the same ethnic group. HLA-B typing was done by PCR SSP method. RESULTS: There was only one HLA-B*15:02 carrier among cases and controls. He/she had SJS/TEN induced by carbamazepine. CONCLUSIONS: Association of HLA-B*15:02 with phenytoin-induced SJS/TEN is rare in the population studied. The one limitation of the study was the small sample size.

Diagnostic utility of HLA-B*5801 screening in severe allopurinol hypersensitivity syndrome: an updated systematic review and meta-analysis.

BACKGROUND: Despite many studies suggesting an association between human leukocyte antigen (HLA)-B*5801 and allopurinol-induced toxic epidermal necrolysis (TEN) and Stevens-Johnsons syndrome (SJS), the evidence of association in different populations and the degree of association remain uncertain. METHODS: The primary analysis was based on population-control studies. Data were pooled by means of a random-effects model, and sensitivity, specificity, positive likelihood ratios (LR+), negative likelihood ratios (LR-), diagnostic odds ratios (DOR), and areas under summary receiver operating characteristic (SROC) curves (AUC) were calculated. RESULTS: In nine population-control studies, HLA-B*5801 was measured in 162 patients with allopurinol-induced TEN/SJS and 7372 patients without allopurinol-induced TEN/SJS. The pooled sensitivity, specificity, LR+, LR-, DOR and AUC were 0.78 (95% CI = 0.71-0.85), 0.96 (95% CI = 0.96-0.97), 14.23 (95% CI = 7.89-25.63), 0.29 (95% CI = 0.16-0.54), 83.5 (95% CI = 50.7-137.4), and 0.97 (95% CI = 0.95-0.99), respectively. Subgroup analyses of the DORs for Chinese, Japanese, and Caucasian populations yielded similar findings for Chinese (196.1; 95% CI = 57.3-672.0), Japanese (78.8; 95% CI = 30.4-203.9), and Caucasian (58.4; 95% CI = 16.9-201.5) populations. Overall, HLA-B*5801 was associated with allopurinol-induced TEN/SJS in European and Japanese populations, but only had a 50-60% sensitivity (pooled sensitivity 56%), compared to the 80-100% sensitivity (pooled sensitivity 97%) observed in Korean, Thai, Sardinia Italian and Han Chinese populations. CONCLUSIONS: The present study reveals that allopurinol is the leading cause of TEN/SJS in many countries. In contrast to carbamazepine, which is ethnic/population specific, the HLA-B*5801 for detecting allopurinol-induced TEN/SJS is universal. Screening of HLA-B*5801 may help patients to prevent the occurrence of allopurinol-induced TEN/SJS, especially in populations with a higher (≥ 5%) risk allele frequency.

HLA-A*24:02 as a common risk factor for antiepileptic drug-induced cutaneous adverse reactions.

OBJECTIVE: To investigate the involvement of human leukocyte antigen (HLA) loci in aromatic antiepileptic drug-induced cutaneous adverse reactions. METHODS: A case-control study was performed to detect HLA loci involved in aromatic antiepileptic drug-induced Stevens-Johnson syndrome in a southern Han Chinese population. Between January 1, 2006, and December 31, 2015, 91 cases of Stevens-Johnson syndrome induced by aromatic antiepileptic drugs and 322 matched drug-tolerant controls were enrolled from 8 centers. Important genotypes were replicated in cases with maculopapular eruption and in the meta-analyses of data from other populations. Sequence-based typing determined the HLA-A, HLA-B, HLA-C, and HLA-DRB1 genotypes. RESULTS: HLA-B*15:02 was confirmed as strongly associated with carbamazepine-induced Stevens-Johnson syndrome (p = 5.63 × 10-15). In addition, HLA-A*24:02 was associated significantly with Stevens-Johnson syndrome induced by the aromatic antiepileptic drugs as a group (p = 1.02 × 10-5) and by individual drugs (carbamazepine p = 0.015, lamotrigine p = 0.005, phenytoin p = 0.027). Logistic regression analysis revealed a multiplicative interaction between HLA-B*15:02 and HLA-A*24:02. Positivity for HLA-A*24:02 and/or HLA-B*15:02 showed a sensitivity of 72.5% and a specificity of 69.0%. The presence of HLA-A*24:02 in cases with maculopapular exanthema was also significantly higher than in controls (p = 0.023). Meta-analysis of data from Japan, Korea, Malaysia, Mexico, Norway, and China revealed a similar association. CONCLUSIONS: HLA-A*24:02 is a common genetic risk factor for cutaneous adverse reactions induced by aromatic antiepileptic drugs in the southern Han Chinese and possibly other ethnic populations. Pretreatment screening is recommended for people in southern China.

Is universal HLA-B*15:02 screening a cost-effective option in an ethnically diverse population? A case study of Malaysia.

BACKGROUND: A strong association has been documented between HLA-B*15:02 and carbamazepine-induced severe cutaneous adverse reactions (SCARs) in Asians. Human leucocyte antigen testing is potentially valuable in many countries to facilitate early recognition of patient susceptibility to SCARs. OBJECTIVES: To determine the cost-effectiveness of universal HLA-B*15:02 screening in preventing carbamazepine-induced Stevens-Johnson syndrome/toxic epidermal necrolysis in an ethnically diverse Malaysian population. METHODS: A hybrid model of a decision tree and Markov model was developed to evaluate three strategies for treating newly diagnosed epilepsy among adults: (i) carbamazepine initiation without HLA-B*15:02 screening (current practice); (ii) universal HLA-B*15:02 screening prior to carbamazepine initiation; and (iii) alternative treatment [sodium valproate (VPA)] prescribing without HLA-B*15:02 screening. Base-case analysis and sensitivity analyses were performed over a lifetime time horizon. Incremental cost-effectiveness ratios were calculated. RESULTS: Both universal HLA-B*15:02 screening and VPA prescribing were dominated by current practice. Compared with current practice, universal HLA-B*15:02 screening resulted in a loss of 0·0255 quality-adjusted life years (QALYs) at an additional cost of 707 U.S. dollars (USD); VPA prescribing resulted in a loss of 0·2622 QALYs at an additional cost of USD 4127, owing to estimated differences in antiepileptic treatment efficacy. CONCLUSIONS: Universal HLA-B*15:02 screening is unlikely to be a cost-effective intervention in Malaysia. However, with the emergence of an ethnically diverse population in many other countries, this may render HLA-B*15:02 screening a viable intervention when an increasing proportion of the population is at risk and an equally effective yet safer antiepileptic drug is available.

A study of HLA-B*15:02 in 9 different Chinese ethnics: Implications for carbamazepine related SJS/TEN.

BACKGROUND: HLA-B*15:02 is a known biomarker for carbamazepine (CBZ)-induced Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) in some ethnic populations. The US FDA recommends B*15:02 screening for Asian and other populations with a high prevalence of B*15:02 prior to treatment with CBZ to prevent drug-related SJS/TEN. MATERIALS AND METHODS: A total of 1607 blood samples were collected from volunteer blood donors who were ethnic minorities living in the Yunnan province of southwestern China, including 153 Yi, 193 Naxi, 167 Miao, 156 Lisu, 166 Derung, 211 Bai, 184 Hani, 198 Dai, and 179 Zhuang. The genetic diversity of the HLA-B*15:02 genes in the ethnic minority samples was examined using sequence based typing at high resolution. RESULTS: The allele frequencies of HLA-B*15:02 in the Yi, Naxi, Miao, Lisu, Derung, Bai, Hani, Dai, and Zhuang populations were 4.25%, 4.4%, 5.09%, 5.77%, 6.33%, 7.82%, 8.15%, 9.6%, and 15.36%, respectively. The frequencies of HLA-B*15:02 carriers in the Yi, Naxi, Miao, Lisu, Derung, Bai, Hani, Dai, and Zhuang populations were 8.5%, 8.8%, 9.58%, 10.9%, 12.65%, 15.64%, 16.3%, 18.69%, and 28.49%, respectively. CONCLUSION: The HLA-B*15:02 allele frequencies indicated that the prevalence of B*15:02 was different among the different ethnic populations. Because the number of carriers of B*15:02 was high in some ethnic populations, larger studies are required to confirm these findings. The Zhuang population had the highest frequency of B*15:02 in this study. More attention should be paid to CBZ-induced SJS/TEN in Chinese minority populations.

The cost-effectiveness of HLA-B*5801 screening to guide initial urate-lowering therapy for gout in the United States.

OBJECTIVE: Positive HLA-B*5801 carriers are at greater risk of experiencing rare but severe allopurinol hypersensitivity syndrome (AHS) [i.e., Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN)]; however, HLA-B*5801 prevalence and AHS risk vary by race/ethnicity. We evaluated the cost-effectiveness of HLA-B*5801 testing according to race/ethnicity in the United States. METHODS: We determined the cost-effectiveness of universal testing for HLA-B*5801 compared to no testing prior to the initiation of allopurinol per US major race/ethnicity groups. Using US-specific data, SJS/TEN risks and HLA-B*5801 prevalences were modeled per race/ethnicity (i.e., 1/3846 and 0.7% among Caucasians and Hispanics, 1/735 and 3.8% among African Americans, and 1/336 and 7.4% among Asians, respectively). Those who tested positive for HLA-B*5801 received febuxostat. Costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs) were estimated over a lifetime. RESULTS: Compared to no testing, universal testing for HLA-B*5801 costs more and was more effective for all races/ethnicities. The ICERs varied substantially across racial/ethnic groups, following their HLA-B*5801 prevalences. HLA-B*5801 testing was cost-effective for African Americans (ICER $83,450) and Asians (ICER $64,190), but not for Caucasians or Hispanics (ICER $183,720), using accepted US willingness-to-pay threshold ($109,000/QALY). Results were robust in sensitivity analyses, except that reducing the risk of SJS/TEN by a half made testing not cost-effective for all races/ethnicities. CONCLUSION: Testing for HLA-B*5801 prior to allopurinol initiation is cost-effective for Asians and African Americans, but not for Caucasians or Hispanics in the United States. Reducing AHS risk by other predictive measures could make HLA-B*5801 testing not cost-effective even among Asians and Blacks.

HLA Allele Frequencies in 5802 Koreans: Varied Allele Types Associated with SJS/TEN According to Culprit Drugs.

PURPOSE: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are very serious forms of drug-induced cutaneous adverse reaction. SJS/TEN induced by certain drug is well known to be associated with some human leukocyte antigen (HLA) gene type. We aimed to explore HLA allele frequencies and their association with SJS/TEN according to culprit drugs in Korea. MATERIALS AND METHODS: We enrolled 5802 subjects who had results of HLA typing test from August 2005 to July 2014. Total 28 SJS/TEN patients were categorized based on culprit drugs (allopurinol, lamotrigine, carbamazepine) and identified the presence of HLA-B*58:01, HLA-B*44:03, HLA-B*15:02, and HLA-A*31:01. RESULTS: HLA-A*24:02 (20.5%), HLA-B*44:03 (10.0%), and HLA-Cw*01:02 (17.1%) were the most frequent type in HLA-A, -B, and -C genes, respectively. Allele frequencies of HLA-B*58:01, HLA-B*44:03, HLA-A*31:01, and HLA-B*15:02 were 7.0%, 10.0%, 5.0%, and 0.3%, respectively. In 958 allopurinol users, 9 subjects (0.9%) were diagnosed with SJS/TEN. Among them, 8 subjects possessed HLA-B*58:01 allele. SJS/TEN induced by allopurinol was more frequently developed in subjects with HLA-B*58:01 than in subjects without it [odds ratio: 57.4; confidence interval (CI) 7.12-463.50; p<0.001]. Allopurinol treatment, based on screening by HLA-B*58:01 genotyping, could be more cost-effective than that not based on screening. HLA-B*44:03 may be associated with lamotrigine-induced SJS/TEN (odds ratio: 12.75; CI 1.03-157.14; p=0.053). Among carbamazepine users, only two patients experienced SJS/TEN and possessed neither HLA-B*15:02 nor HLA-A*31:03. CONCLUSION: HLA gene frequencies varied in Korea. Screening of HLA-B*58:01 before the use of allopurinol might be needed to anticipate probability of SJS/TEN.

Analysis of Ocular Manifestation and Genetic Association of Allopurinol-Induced Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis in South Korea.

PURPOSE: To describe the clinical characteristics and genetic background of allopurinol-induced Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) in South Korea. METHODS: This is a prospective, noncomparative case series. Visual acuity, detailed medical history, ocular findings, and systemic manifestations of 5 patients (10 eyes) with allopurinol-induced SJS/TEN were recorded. The acute ocular involvement score and the chronic ocular manifestation score were graded on scales of 0-3 and 0-39, respectively, based on severity. Human leukocyte antigen (HLA) genotyping was also performed during the hospitalization. RESULTS: Three patients were diagnosed with SJS, and 2 with TEN. Mild ocular involvement with only conjunctival hyperemia (acute ocular involvement score ≤ 1) was present in all 10 eyes during the acute stage. Patients were treated with systemic steroids and topical antibiotics, steroids, and preservative-free artificial tears, with rinsing of the ocular surface, in the acute stages of SJS/TEN. In the final follow-up, none of the patients had developed severe chronic ocular complications (chronic ocular manifestation score ≤ 8), including keratinization, corneal conjunctivalization, mucocutaneous junction involvement, or symblepharon. One patient developed bilateral persistent epithelial defects 3 months after the disease onset, which healed after conservative treatment, leaving a bilateral central corneal haze. HLA genotyping showed that 4 of the 5 patients (80%) were positive for HLA-B*58:01. CONCLUSIONS: Allopurinol-induced SJS/TEN might not cause serious acute or chronic complications of the ocular surface. In addition, our HLA genotyping results are consistent with previous studies reporting a strong association between HLA-B*58:01 and allopurinol-induced SJS/TEN among Koreans.

HLA-B*59:01: a marker for Stevens-Johnson syndrome/toxic epidermal necrolysis caused by methazolamide in Han Chinese.

Methazolamide is an intraocular pressure-lowering drug that is used in the treatment of glaucoma and other ophthalmologic abnormalities. The use of methazolamide has been shown to cause Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) in patients of Asian ancestry. Methazolamide-induced SJS/TEN is associated with the presence of HLA-B59 serotype/HLA-B*59:01 in Korean and Japanese populations. To better understand the genetic risk factors for these adverse reactions in the Han Chinese population, we characterized the HLA class I genotypes of eight Chinese patients with methazolamide-induced SJS/TEN from 2008 to 2014. The frequency of HLA-B*59:01 was 87.5% (7/8) in the case patients, which was significantly different from 0% (0/30) in the methazolamide-tolerant patients (odds ratio (OR)=305.0; P=6.3 × 10(-7)) and 0.35% (1/283) in healthy subjects from the human major histocompatibility complex database (OR=1974.0; P=2.0 × 10(-12)). HLA-C*01:02, which is closely linked to HLA-B*59:01, had a weaker but notable association with methazolamide-induced SJS/TEN compared with the tolerant controls (OR=12.1; P=0.016) and general population (OR=15.5; P=2.0 × 10(-3)). The distribution of the HLA-B*59:01-C*01:02 haplotype was also significantly different in cases and controls. This study demonstrated a strong association between HLA-B*59:01 and methazolamide-induced SJS/TEN in the Han Chinese population for the first time. Pretherapy screening for HLA-B*59:01 would be useful to reduce the risk of methazolamide-induced SJS/TEN.

HLA Allele Frequencies in 5802 Koreans: Varied Allele Types Associated with SJS/TEN According to Culprit Drugs

PURPOSE: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are very serious forms of drug-induced cutaneous adverse reaction. SJS/TEN induced by certain drug is well known to be associated with some human leukocyte antigen (HLA) gene type. We aimed to explore HLA allele frequencies and their association with SJS/TEN according to culprit drugs in Korea. MATERIALS AND METHODS: We enrolled 5802 subjects who had results of HLA typing test from August 2005 to July 2014. Total 28 SJS/TEN patients were categorized based on culprit drugs (allopurinol, lamotrigine, carbamazepine) and identified the presence of HLA-B*58:01, HLA-B*44:03, HLA-B*15:02, and HLA-A*31:01. RESULTS: HLA-A*24:02 (20.5%), HLA-B*44:03 (10.0%), and HLA-Cw*01:02 (17.1%) were the most frequent type in HLA-A, -B, and -C genes, respectively. Allele frequencies of HLA-B*58:01, HLA-B*44:03, HLA-A*31:01, and HLA-B*15:02 were 7.0%, 10.0%, 5.0%, and 0.3%, respectively. In 958 allopurinol users, 9 subjects (0.9%) were diagnosed with SJS/TEN. Among them, 8 subjects possessed HLA-B*58:01 allele. SJS/TEN induced by allopurinol was more frequently developed in subjects with HLA-B*58:01 than in subjects without it [odds ratio: 57.4; confidence interval (CI) 7.12-463.50; p<0.001]. Allopurinol treatment, based on screening by HLA-B*58:01 genotyping, could be more cost-effective than that not based on screening. HLA-B*44:03 may be associated with lamotrigine-induced SJS/TEN (odds ratio: 12.75; CI 1.03-157.14; p=0.053). Among carbamazepine users, only two patients experienced SJS/TEN and possessed neither HLA-B*15:02 nor HLA-A*31:03. CONCLUSION: HLA gene frequencies varied in Korea. Screening of HLA-B*58:01 before the use of allopurinol might be needed to anticipate probability of SJS/TEN.

IKZF1, a new susceptibility gene for cold medicine-related Stevens-Johnson syndrome/toxic epidermal necrolysis with severe mucosal involvement.

BACKGROUND: Stevens-Johnson syndrome (SJS) and its severe form, toxic epidermal necrolysis (TEN), are acute inflammatory vesiculobullous reactions of the skin and mucous membranes, including the ocular surface, oral cavity, and genitals. These reactions are very rare but are often associated with inciting drugs, infectious agents, or both. OBJECTIVE: We sought to identify susceptibility loci for cold medicine-related SJS/TEN (CM-SJS/TEN) with severe mucosal involvement (SMI). METHODS: A genome-wide association study was performed in 808 Japanese subjects (117 patients with CM-SJS/TEN with SMI and 691 healthy control subjects), and subsequent replication studies were performed in 204 other Japanese subjects (16 cases and 188 control subjects), 117 Korean subjects (27 cases and 90 control subjects), 76 Indian subjects (20 cases and 56 control subjects), and 174 Brazilian subjects (39 cases and 135 control subjects). RESULTS: In addition to the most significant susceptibility region, HLA-A, we identified IKZF1, which encodes Ikaros, as a novel susceptibility gene (meta-analysis, rs4917014 [G vs. T]; odds ratio, 0.5; P = 8.5 × 10(-11)). Furthermore, quantitative ratios of the IKZF1 alternative splicing isoforms Ik1 and Ik2 were significantly associated with rs4917014 genotypes. CONCLUSION: We identified IKZF1 as a susceptibility gene for CM-SJS/TEN with SMI not only in Japanese subjects but also in Korean and Indian subjects and showed that the Ik2/Ik1 ratio might be influenced by IKZF1 single nucleotide polymorphisms, which were significantly associated with susceptibility to CM-SJS/TEN with SMI.

Steven's Johnson syndrome with toxic epidermal necrolysis due to thalidomide in a case of multiple myeloma.

Thalidomide developed in 1954 for morning sickness had proven to be a teratogen and hence was withdrawn from market. Resurgence of thalidomide began as an immunomodulator when it was shown to be effective in the management of multiple myeloma and many conditions like erythema nodosum leprosum, graft versus host disease, recurrent aphthous ulcers etc. We report a case of Stevens Johnson syndrome-toxic epidermal necrolysis developing in an elderly male who was prescribed thalidomide after being diagnosed with multiple myeloma.

Trans-ethnic study confirmed independent associations of HLA-A*02:06 and HLA-B*44:03 with cold medicine-related Stevens-Johnson syndrome with severe ocular surface complications.

Stevens-Johnson syndrome (SJS) and its severe variant, toxic epidermal necrolysis (TEN), are acute inflammatory vesiculobullous reactions of the skin and mucous membranes. Cold medicines including non-steroidal anti-inflammatory drugs and multi-ingredient cold medications are reported to be important inciting drugs. Recently, we reported that cold medicine related SJS/TEN (CM-SJS/TEN) with severe mucosal involvement including severe ocular surface complications (SOC) is associated with HLA-A*02:06 and HLA-B*44:03 in the Japanese. In this study, to determine whether HLA-B*44:03 is a common risk factor for CM-SJS/TEN with SOC in different ethnic groups we used samples from Indian, Brazilian, and Korean patients with CM-SJS/TEN with SOC, and investigated the association between CM-SJS/TEN with SOC and HLA-B*44:03 and/or HLA-A*02:06. We found that HLA-B*44:03 was significantly associated with CM-SJS/TEN with SOC in the Indian and Brazilian but not the Korean population, and that HLA-A*02:06 might be weakly associated in the Korean- but not the Indian and Brazilian population.

Epilepsy in adults.

BACKGROUND: Epilepsy is a common disorder and most adult patients will be managed primarily by general practitioners. Despite new developments in the classification and treatment of epilepsy, basic principles of diagnosis and treatment remain valid, such as the importance of an accurate, detailed history and adjusting antiepileptic drug (AED) doses on the basis of seizure control and adverse effects rather than blood test results. OBJECTIVE: This article addresses current issues in the diagnosis and management of epilepsy, including initial evaluation and use of AEDs. DISCUSSION: Older AEDs are still prescribed commonly; newer AEDs have similar efficacy and improved tolerability. Human leukocyte-associated antigen (HLA) testing is recommended before commencing Asian patients on carbamazepine to minimise the risk of Stevens-Johnson syndrome (SJS). Referral to an epilepsy specialist is recommended if seizures are not controlled after trialling two AEDs. Important issues pertaining to reproductive and bone health are complex and poorly understood.

Association of HLA-B*1502 and *1511 allele with antiepileptic drug-induced Stevens-Johnson syndrome in central China.

Previous studies have demonstrated a strong association between carbamazepine (CBZ)-induced Stevens-Johnson syndrome (SJS) and HLA-B*1502 in Han Chinese. Here, we extended the study of HLA-B*1502 susceptibility to two different antiepileptic drugs, oxcarbazepine (OXC) and phenobarbital (PB). In addition, we genotyped HLA-B*1511 in a case of CBZ-induced SJS with genotype negative for HLA-B*1502. The presence of HLA-B*1502 was determined using polymerase chain reaction with sequence-specific primers (PCR-SSP). Moreover, we genotyped HLA-B*1502 in 17 cases of antiepileptic drugs (AEDs)-induced cutaneous adverse drug reactions (cADRs), in comparison with AEDs-tolerant (n=32) and normal controls (n=38) in the central region of China. The data showed that HLA-B*1502 was positive in 5 of 6 cases of AEDs-induced SJS (4 CBZ, 1 OXC and 1 PB), which was significantly more frequent than AEDs-tolerant (2/32, 18 CBZ, 6 PB and 8 OXC) and normal controls (3/38). Compared with AEDs-tolerant and normal controls, the OR for patients carrying the HLA-B*1502 with AEDs-induced SJS was 6.25 (95% CI: 1.06-36.74) and 4.86 (95% CI: 1.01-23.47). The sensitivity and specificity of HLA-B*1502 for prediction of AEDs-induced SJS were 71.4%. The sensitivity and specificity of HLA-B*1502 for prediction of CBZ-induced SJS were 60% and 94%. HLA-B*1502 was not found in 11 children with maculopapular exanthema (MPE) (n=9) and hypersensitivity syndrome (HSS) (n=2). However, we also found one case of CBZ-induced SJS who was negative for HLA-B*1502 but carried HLA-B*1511. It was suggested that the association between the CBZ-induced SJS and HLA-B*1502 allele in Han Chinese children can extend to other aromatic AEDs including OXC and PB related SJS. HLA-B*1511 may be a risk factor for some patients with CBZ-induced SJS negative for HLA-B*1502.