Clinical features of and genetic predisposition to drug-induced Stevens–Johnson syndrome and toxic epidermal necrolysis in a single Korean tertiary institution patients—investigating the relation between the HLA -B*4403 allele and lamotrigine

Pharmacogenomics predictors of aromatic antiepileptic drugs-induced SCARs in the Iraqi patients

Introduction

Severe cutaneous adverse reactions (SCARs) are life-threatening and often linked to antiepileptic drugs (AEDs). Common types of SCARs include Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and drug reaction with eosinophilia and systemic symptoms (DRESS). Immune-mediated mechanisms involving human leukocyte antigen (HLA) alleles have been implicated in the pathogenesis of this reaction. This study examines the association between specific HLA alleles (HLA-A, -B, and -DRB1) and AED-induced SCARs in the Iraqi population.

Methodology

A total of 50 patients diagnosed with SCARs and 90 tolerant controls were recruited from Dr. Saad Al-Wattari Hospital for Neurological Sciences and Baghdad Hospital - Medical City. HLA genotyping was performed using PCR-SSO method from peripheral blood samples. Statistical comparisons were made using the t-test or chi-square test, while univariate logistic regression with Bonferroni's correction (p < 0.05) were used to assess associations between HLA alleles and SCARs.

Results

Among the patients, SJS was the most prevalent type of SCARs observed. Analysis of HLA allele frequencies revealed significant associations between specific alleles. HLA-A∗02:01 was found to be significantly associated with a lower risk of AED-induced SJS (OR = 0.36; 95 % CI: 0.13-0.97), while HLA-A∗24:02 and HLA-B∗15:02 were associated with an increased risk of AED-induced SJS (OR = 3.60; 95 % CI: 1.21-10.72 and OR = 4.41; 95 % CI: 1.18-16.47, respectively). For AED-induced TEN, HLA-A∗01:02, HLA-B∗15:02, and HLA-B∗52:01 showed significant associations (OR = 6.92; 95 % CI: 1.39-34.37 and OR = 6.55; 95 % CI: 1.62-26.52, respectively), with HLA-DRB1∗03:01 being highly significant (OR = 5.09; 95 % CI: 1.72-15.00). Additionally, HLA-B∗40:02 was strongly associated with AED-induced DRESS (OR = 29.33; 95 % CI: 3.50-245.32).

Conclusion

This study identifies key HLA alleles associated with AED-induced SCARs in the Iraqi population. These findings could facilitate personalized medicine approaches, aiding in better prediction and prevention of SCARs in AED therapy.

Unraveling the genetic link: an umbrella review on HLA-B*15:02 and antiepileptic drug-induced Stevens-Johnson syndrome/toxic epidermal necrolysis

PURPOSE

This umbrella review was conducted to summarize the association between HLA*1502 allele with antiepileptic induced Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN).

METHODS

Pubmed, Scopus and EMBASE were searched for eligible reviews in May 2023. Two authors independently screened titles and abstracts and assessed full-text reviews for eligibility. The quality of meta-analyses and case-control studies was appraised with Assessing the Methodological Quality of Systematic Reviews 2 and Newcastle-Ottawa Scale, respectively. Narrative summaries of each antiepileptic drug were analyzed. Preestablished protocol was registered on the International Prospective Register of Systematic Reviews Registry(ID: CRD42023403957).

RESULTS

Included studies are systematic reviews, meta-analyses and case-control studies evaluating the association of HLA-B*1502 allele with the following antiepileptics. Seven meta-analyses for carbamazepine, three meta-analyses for lamotrigine (LTG), three case-control studies for oxcarbazepine, nine case-control studies for phenytoin and four case-control studies for phenobarbitone were included. The findings of this umbrella review suggest that there is a strong association between HLA-B-1502 with SJS/TEN for carbamazepine and oxcarbazepine and a milder association for lamotrigine and phenytoin.

CONCLUSION

In summary, although HLA-B*1502 is less likely to be associated with phenytoin or lamotrigine-induced SJS/TEN compared to carbamazepine-induced SJS/TEN, it is a significant risk factor that if carefully screened, could potentially reduce the development of SJS/TEN. In view of potential morbidity and mortality, HLA-B*1502 testing may be beneficial in patients who are initiating lamotrigine/phenytoin therapy. However, further studies are required to examine the association of other alleles with the development of SJS/TEN and to explore the possibility of genome-wide association studies before initiation of treatment.

Genetic Determinants in HLA and Cytochrome P450 Genes in the Risk of Aromatic Antiepileptic-Induced Severe Cutaneous Adverse Reactions

Adverse drug reaction (ADR) is a pressing health problem, and one of the main reasons for treatment failure with antiepileptic drugs. This has become apparent in the event of severe cutaneous adverse reactions (SCARs), which can be life-threatening. In this review, four hypotheses were identified to describe how the immune system is triggered in the development of SCARs, which predominantly involve the human leukocyte antigen (HLA) proteins. Several genetic variations in HLA genes have been shown to be strongly associated with the susceptibility to developing SCARs when prescribed carbamazepine or phenytoin. These genetic variations were also shown to be prevalent in certain populations. Apart from the HLA genes, other genes proposed to affect the risk of SCARs are genes encoding for CYP450 drug-metabolising enzymes, which are involved in the pharmacokinetics of offending drugs. Genetic variants in CYP2C9 and CYPC19 enzymes were also suggested to modulate the risk of SCARs in some populations. This review summarizes the literature on the manifestation and aetiology of antiepileptic-induced SCARs, updates on pharmacogenetic markers associated with this reaction and the implementation of pre-emptive testing as a preventive strategy for SCARs.

Drug-Induced Skin Adverse Reactions: The Role of Pharmacogenomics in Their Prevention

Adverse drug reactions (ADRs) affect many patients and remain a major public health problem, as they are a common cause of morbidity and mortality. It is estimated that ADRs are responsible for about 6% of hospital admissions and about 9% of hospitalization costs. Skin is the organ that is most frequently involved in ADRs. Drug-induced skin injuries vary from mild maculopapular eruptions (MPE) to severe cutaneous adverse reactions (SCARs) that are potentially life threatening. Genetic factors have been suggested to contribute to these SCARs, and most significant genetic associations have been identified in the major histocompatibility complex (MHC) genes. Common drugs associated with SCARs connected with strong genetic risk factors include antiepileptic drugs (AEDs), allopurinol, abacavir, nevirapine, sulfonamides, dapsone, non-steroidal anti-inflammatory drugs (NSAIDs), and analgesic drugs. However, genetic associations vary between different ethnic populations. Differences may in part be explained by the different prevalence of HLA (human leukocyte antigen) alleles among ethnic groups. In this review, we present and discuss the recent advances in genetic associations with ADRs in the skin. Many of these ADRs are now preventable with pharmacogenetic screening.

Association of HLA-A and HLA-B Alleles with Lamotrigine-Induced Cutaneous Adverse Drug Reactions in the Thai Population

Background: Lamotrigine (LTG) is commonly used for treatment of epilepsy and bipolar disorder. It is one of the common cause of cutaneous adverse drug reactions (CADR). Clinical symptoms of LTG-induced CADR range from maculopapular exanthema (MPE) to severe cutaneous adverse reactions (SCAR). This study aimed to determine the association of the LTG-induced CADR with human leukocyte antigen (HLA) alleles in Thai patients.

Methods: Fifteen patients with LTG-induced CADR [10 MPE; 4 Stevens–Johnson syndrome; and 1 drug reaction with eosinophilia and systemic symptoms] and 50 LTG-tolerant controls were included in the study. HLA-A and HLA-B genotyping was performed using polymerase chain reaction-sequence-specific oligonucleotides probes.

Results: The proportion of HLA-A^∗02:07 and HLA-B^∗15:02 allele carriers were significantly higher in the LTG-induced CADR group than in the tolerant controls [odds ratio (OR): 7.83; 95% confidence interval (CI): 1.60–38.25; P = 0.013, and OR: 4.89; 95% CI: 1.28–18.67; P = 0.014]. In addition, subjects with HLA-A^∗33:03, HLA-B^∗15:02, and HLA-B^∗44:03 were significantly higher in the LTG-induced MPE group than in the tolerant controls (OR: 8.27; 95% CI: 1.83–37.41; P = 0.005, OR: 7.33; 95% CI: 1.63–33.02; P = 0.005; and OR: 10.29; 95% CI: 1.45–72.81; P = 0.029). In contrast to the LTG-induced MPE group, there were no significant differences between HLA alleles and LTG-induced SCAR group.

Conclusion:HLA-A^∗02:07 and HLA-B^∗15:02 were associated with LTG-induced CADR in Thai patients. We also identified an association between HLA-A^∗33:03, HLA-B^∗15:02, and HLA-B^∗44:03 and LTG-induced MPE in this population. These results suggest that these alleles could be useful screening markers for preventing CADR before LTG treatment in Thai patients, but further replication studies with larger sample sizes are needed.

Is acetaminophen associated with a risk of Stevens-Johnson syndrome and toxic epidermal necrolysis? Analysis of the French Pharmacovigilance Database

AIM

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare but severe mostly drug-induced cutaneous reactions. Acetaminophen is an over-the-counter drug used worldwide to treat pain and reduce fever. In 2013, the US Food and Drug Administration informed the public that acetaminophen was associated with a rare risk of SJS/TEN. The aim of the present retrospective study was to analyse reports of acetaminophen as a possible suspect in the development of SJS/TEN from the French Pharmacovigilance Database (FPDB).

METHODS

Cases of TEN/SJS with acetaminophen as a suspect drug registered in the FPDB, collected from January 2002 to December 2013, were analysed by an expert group. The algorithm of drug causality for epidermal necrolysis (ALDEN) was used as a reference tool for SJS/TEN to assess the causality of each suspect drug.

RESULTS

After exclusion of 16 nonvalidated cases, 112 cases (47 TEN, 51 SJS, 14 SJS/TEN overlaps) involving 574 suspected drugs (5⋅1/case) were analysed. In 80 cases, the acetaminophen ALDEN score was inferior or equal to that of other drugs, associated with a higher suspicion for causality. In 32 cases, acetaminophen had the highest score but matched with a 'very unlikely' or 'unlikely' causality in 12 cases. For the 20 remaining cases with a 'possible' or ' probable' causality, a protopathic or a confounding bias was likely in 14 cases.

CONCLUSIONS

After analysis of the French pharmacovigilance data using the ALDEN algorithm, we found no obvious SJS/TEN risk related to the use of acetaminophen in this large national series.

An update on HLA alleles associated with adverse drug reactions

Adverse drug reactions (ADRs) are considered as an important cause of morbidity and mortality. The hypersensitivity reactions are immune-mediated ADRs, which are dose-independent, unpredictable and have been associated with several HLA alleles. The present review aimed to describe HLA alleles that have been associated with different ADRs in populations worldwide, the recommendations of regulatory agencies and pharmacoeconomic information and databases for the study of HLA alleles in pharmacogenetics. A systematic search was performed in June 2016 of articles relevant to this issue in indexed journals and in scientific databases (PubMed and PharmGKB). The information of 95 association studies found was summarized. Several HLA alleles and haplotypes have been associated with ADRs induced mainly by carbamazepine, allopurinol, abacavir and nevirapine, among other drugs. Years with the highest numbers of publications were 2013 and 2014. The majority of the reports have been performed on Asians and Caucasians, and carbamazepine was the most studied ADR drug inducer. Two HLA alleles' databases are described, as well as the recommendations of the U.S. Food and Drug Administration, the European Medicine Agency and the Clinical Pharmacogenetics Implementation Consortium. Pharmacoeconomic studies on this issue are also mentioned. The strongest associations remain for HLA-B*58:01, HLA-B*57:01, HLA-B*15:02 and HLA-A*31:01 but only in certain populations; therefore, studies on different ethnic groups would be useful. Due to the improvement of drug therapy and the economic benefit that HLA screening represents, investigations on HLA alleles associated with ADR should continue.

Identifying the incidence of rash, Stevens-Johnson syndrome and toxic epidermal necrolysis in patients taking lamotrigine: a systematic review of 122 randomized controlled trials

Lamotrigine is an antiepileptic drug used for the treatment of epilepsy, bipolar disorder and numerous off-label uses. The development of rash significantly affects its use. The most concerning of these adverse reactions is Stevens-Johnson syndrome/toxic epidermal necrolysis. We performed a systematic review of randomized controlled trials using lamotrigine as a monotherapy to quantify the incidence of cutaneous reactions, particularly Stevens-Johnson syndrome/toxic epidermal necrolysis. Of a total of 4,364 papers regarding lamotrigine, 122 studies met our inclusion and exclusion criteria. In total, 18,698 patients were included with 1,570 (8.3%) of patients experiencing an adverse dermatologic reaction. The incidence of Stevens-Johnson syndrome/toxic epidermal necrolysis was 0.04%.

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.

Stevens-Johnson syndrome and toxic epidermal necrolysis: an update on pharmacogenetics studies in drug-induced severe skin reaction

Stevens-Johnson syndrome and toxic epidermal necrolysis are severe, life-threatening drug reactions involving skin and membranes mucous, which are associated with significant morbidity and mortality and triggered, especially by drug exposure. Different studies have demonstrated that drug response is a multifactorial character and that the interindividual variability in this response depends on both environmental and genetic factors. The last ones have a relevant significance. In fact, the identification of new specific genetic markers involved in the response to drugs, will be of great utility to establish a more personalized therapeutic approach and to prevent the appearance of these adverse reactions. In this review, we summarize recent progresses in the Pharmacogenetics studies related to Stevens-Johnson syndrome/toxic epidermal necrolysis reporting the major genetic factors identified in the last years as associated with the disease and highlighting the use of some of these genomic variants in the clinical practice.