Influence of pharmacogenomic polymorphisms on allopurinol-induced cutaneous adverse drug reactions in Thai patients

BACKGROUND

Allopurinol has been causing substantial morbidity and mortality particularly in Asian population by producing cutaneous adverse drug reactions (cADRs). Nonetheless, there are no data describing whether other genetics are a valid marker for prediction of allopurinol-induced cADRs patients in addition to HLA-B*58:01 allele. The goal of this study was to identify suitable single nucleotide polymorphisms (SNPs) for allopurinol induced cADRs among Thai patients.

METHODS

We conducted a case-control association study after enrolling 57 Thai patients with allopurinol induced cADRs and 101 allopurinol-tolerant controls. The genetic biomarkers and associated SNPs located on chromosome 6p21 were examined by TaqMan® SNP genotyping assays in both the cases and the controls.

RESULTS

Out of fifteen SNPs in nine genes, we found four combined SNPs (rs3099844 of HCP5, rs9263726 of PSORS1C1, rs9263733 of POLR2LP, and rs9263745 of CCHCR1) were significantly associated with allopurinol-induced cADRs compared to the tolerant controls (OR 73.2; 95% CI 24.2-266.8; P = 1.9 × 10- 24). The overall sensitivity, specificity, positive predictive value and negative predictive value of these combinations were 84%, 94%, 9%, and 100%, respectively. However, the variant alleles of these SNP combinations were detected in 89.5% (51/57) of the cases. Moreover, the HLA-B*58:01 allele was observed in 86.0% of patients with allopurinol-induced cADRs, but only in 4.0% of tolerant controls (OR: 137.2; 95% CI: 38.3-670.5 and p-value = 1.7 × 10- 27).

CONCLUSIONS

Thus, this research confirms the association between the specific HLA-B*58:01 allele and all phenotypes of allopurinol-induced cADRs in Thais. Furthermore, there was found the combined four SNPs (rs3099844, rs9263726, rs9263733, and rs9263745) could be used as alternative novel biomarkers for predicting cADRs in patients taking allopurinol.

IFN-γ ELISpot-enabled machine learning for culprit drug identification in nonimmediate drug hypersensitivity

BACKGROUND

Diagnosing drug-induced allergy, especially nonimmediate phenotypes, is challenging. Incorrect classifications have unwanted consequences.

OBJECTIVE

We sought to evaluate the diagnostic utility of IFN-γ ELISpot and clinical parameters in predicting drug-induced nonimmediate hypersensitivity using machine learning.

METHODS

The study recruited 393 patients. A positive patch test or drug provocation test (DPT) was used to define positive drug hypersensitivity. Various clinical factors were considered in developing random forest (RF) and logistic regression (LR) models. Performances were compared against the IFN-γ ELISpot-only model.

RESULTS

Among the 102 patients who had 164 DPTs, most patients had severe cutaneous adverse reactions (35/102, 34.3%) and maculopapular exanthems (33/102, 32.4%). Common suspected drugs were antituberculosis drugs (46/164, 28.1%) and β-lactams (42/164, 25.6%). Mean (SD) age of patients with DPT was 52.7 (20.8) years. IFN-γ ELISpot, fixed drug eruption, Naranjo categories, and nonsteroidal anti-inflammatory drugs were the most important features in all developed models. The RF and LR models had higher discriminating abilities. An IFN-γ ELISpot cutoff value of 16.0 spot-forming cells/106 PBMCs achieved 94.8% specificity and 57.1% sensitivity. Depending on clinical needs, optimal cutoff values for RF and LR models can be chosen to achieve either high specificity (0.41 for 96.1% specificity and 0.52 for 97.4% specificity, respectively) or high sensitivity (0.26 for 78.6% sensitivity and 0.37 for 71.4% sensitivity, respectively).

CONCLUSIONS

IFN-γ ELISpot assay was valuable in identifying culprit drugs, whether used individually or incorporated in a prediction model. Performances of RF and LR models were comparable. Additional test datasets with DPT would be helpful to validate the model further.

Efficacy and safety of fractional 1064-nm picosecond laser for atrophic traumatic and surgical scars: A randomized, single-blinded, split-scar-controlled study

OBJECTIVE

A fractional 1064-nm picosecond laser is an efficient and safe treatment for atrophic acne scars. However, evidence of using a picosecond laser for atrophic posttraumatic and surgical scar therapy is lacking. This study aimed to evaluate the efficacy and safety of using a 1064-nm picosecond laser with a microlens array (MLA) for the treatment of atrophic posttraumatic and surgical scars.

METHODS

This was a prospective, intraindividual, single-blinded, randomized split-lesion-controlled trial. Twenty-five subjects with atrophic traumatic or surgical scars that existed for more than 1 year were enrolled. All atrophic scars were divided at the midline into two halves and randomly assigned to a treatment or control side. The treatment group was treated with a 1064-nm picosecond laser with an MLA handpiece (spot size: 6-8 mm, fluence: 1.0-1.2 J/cm² , repetition rate: 5 Hz, three passes) for 3 monthly sessions. The scar volumes were objectively measured using a three-dimensional (3D) photograph at baseline, 1 month after the first and second treatments, and 3 and 6 months after the final treatment. Subjective assessments were conducted by a blinded dermatologist and patients' self-assessment to evaluate improvements at 3 months after the final treatment.

RESULTS

The treated sides exhibited a significant volume reduction, with statistically significant improvements over the control group at 1 month after the first and second treatments and at 3 months after the final treatment (p = 0.024, 0.005, and 0.019, respectively). At 3 months after the final treatment, a blinded dermatologist correctly identified the treated side in 24 of 25 patients (96%). The patients rated the improvements as excellent (>75%) and marked (50%-75%) in 36% and 48% of patients, respectively.

CONCLUSION

At 3 months, the 1064-nm picosecond laser with a fractionated MLA can significantly reduce the posttraumatic and postsurgical atrophic scar volume in patients with Fitzpatrick skin types III-V. Insufficient data preclude inferences regarding efficacy at 6 months.

Efficacy of a triamcinolone acetonide-loaded dissolving microneedle patch for the treatment of hypertrophic scars and keloids: a randomized, double-blinded, placebo-controlled split-scar study

The treatment of hypertrophic scars (HTSs) and keloids remains a challenge. Intralesional triamcinolone acetonide (TAC) is the mainstay treatment for these conditions. Despite its efficacy, TAC has several adverse side effects, including telangiectasias, skin atrophy, pigmentary changes, and skin necrosis. Dissolving microneedles (DMN) use the poke-and-release method to create microchannels that enhance drug delivery to the target tissue in the dermis, without causing pain and with a decreased risk of transmission of blood-borne diseases. To evaluate and compare the efficacy of a TAC-DMN versus a drug-free DMN patch for the treatment of HTSs and keloids, 20 patients (10 with HTSs and 10 with keloids) received a split-scar treatment: one half of the scar length was treated with TAC-DMNs and the other half was treated with drug-free DMN for three sessions at 14-day intervals. Efficacy was assessed by measuring the scar volume through a multispectral imaging system and using the Patient and Observer Scar Assessment Scale (POSAS). The HTSs treated with TAC-DMNs showed a significant reduction in the mean scar volume 2 weeks after the second treatment and 1 month after the third treatment (p = 0.028 and 0.020, respectively), while the HTSs treated with drug-free DMNs showed no significant reduction in the scar volume. Both sides of the keloids showed no significant reduction in mean scar volume. Using the POSAS, significant improvement in the appearance of both halves of the HTSs was observed 1 month after the treatments. A significant improvement (evaluated by POSAS) was also observed in the keloids treated with TAC-DMNs 2 weeks after the second treatment and 1 month after the third treatment. No significant improvement was observed from the patients' perspective as evaluated by POSAS in the keloids treated with drug-free DMNs. However, no significant difference was observed between the treatment and control halves. TAC-DMN is an effective treatment for HTSs. Increasing the dosage and duration of keloid scar treatment is required in future studies to determine whether it would result in a significant therapeutic outcome. This trial is registered in the Thai Clinical Trials Registry (TCTR20220318004; date of registration, March 17, 2022).

The Role of In Vitro Detection of Drug-Specific Mediator-Releasing Cells to Diagnose Different Phenotypes of Severe Cutaneous Adverse Reactions

PROPOSE

The purpose of this study was to investigate panels of enzyme-linked immunospot assays (ELISpot) to detect drug-specific mediator releasing cells for confirming culprit drugs in severe cutaneous adverse reactions (SCARs).

METHODS

Frequencies of drug-induced interleukin-22 (IL-22)-, interferon-gamma (IFN-γ)-, and granzyme-B (GrB)-releasing cells were measured by incubating peripheral blood mononuclear cells (PBMCs) from SCAR patients with the culprit drugs. Potential immunoadjuvants were supplemented to enhance drug-induced mediator responses.

RESULTS

Twenty-seven patients, including 9 acute generalized exanthematous pustulosis (AGEP), 10 drug reactions with eosinophilia and systemic symptoms, and 8 Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) were recruited. The average frequencies of drug-induced IL-22-, IFN-γ-, and GrB-releasing cells were 35.5±16.3, 33.0±7.1, and 164.8±43.1 cells/million PBMCs, respectively. The sensitivity of combined IFN-γ/IL-22/GrB ELISpot was higher than that of IFN-γ ELISpot alone for culprit drug detection in all SCAR subjects (77.8% vs 51.9%, P < 0.01). The measurement of drug-induced IL-22- and IFN-γ releasing cells confirmed the culprit drugs in 77.8% of AGEP. The measurement of drug-induced IFN-γ- and GrB-releasing cells confirmed the culprit drugs in 62.5% of SJS/TEN. Alpha-galactosylceramide supplementation significantly increased the frequencies of drug-induced IFN-γ releasing cells.

CONCLUSION

The measurement of drug-induced IFN-γ-releasing cells is the key for identifying culprit drugs. The additional measurement of drug-induced IL-22-releasing cells enhances ELISpot sensitivity to identify drug-induced AGEP, while the measurement of drug-induced GrB-releasing cells could have a role in SJS/TEN. ELISpot sensitivity might be improved by supplementary alpha-galactosylceramide.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02574988.

Efficacy and safety of 0.15% isobutylamido thiazolyl resorcinol combined with hyaluronic acid vs 0.15% isobutylamido thiazolyl resorcinol or hyaluronic acid alone in melasma treatment: A randomized evaluator-blind trial

BACKGROUND

Melasma has a complex pathogenesis, and various aggravating factors contribute to its recalcitrance to treatments. A combination of isobutylamido thiazolyl resorcinol (ITR) and hyaluronic acid (HA) could increase melasma treatment efficacy.

AIMS

To compare the efficacy and safety of 0.15% ITR plus HA vs 0.15% ITR or HA alone in melasma treatment.

METHODS

Ninety-two patients received ITR 0.15% plus HA (n = 30), 0.15% ITR (n = 31), or HA (n = 31) along with broad-spectrum sunscreen application for 12 weeks. Treatment efficacy was determined using modified Melasma Area Severity Index (mMASI), average melanin and melanin variation with Antera3D^® , and safety based on transepidermal water loss.

RESULTS

Compared with the HA group, the ITR+HA group showed significantly reduced mMASI at weeks 4, 8, and 12 (p = 0.026, 0.015, and 0.001, respectively), whereas the ITR group showed a significant reduction at week 12 (p = 0.027). There was no significant difference in the mMASI or average melanin level between the ITR+HA and ITR groups. Melanin variation was significantly lower in the ITR+HA group than in the ITR group at weeks 4, 8, and 12 (p = 0.027, 0.019, and 0.023, respectively).

CONCLUSIONS

The combination of 0.15% ITR and 0.15% ITR+HA effectively reduced melasma severity. HA could synergistically improve melasma homogeneity.

Genetic Association of Co-Trimoxazole-Induced Severe Cutaneous Adverse Reactions Is Phenotype-Specific: HLA Class I Genotypes and Haplotypes

Co-trimoxazole (CTX) causes various forms of severe cutaneous adverse reactions (SCARs). This case-control study was conducted to investigate the involvement between genetic variants of human leukocyte antigen (HLA) and CYP2C9 in CTX-induced SCARs, including Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) and drug reaction with eosinophilia and systemic symptoms (DRESS) in Thai patients. Thirty cases of CTX-induced SCARs were enrolled and compared with 91 CTX-tolerant controls and 150 people from the general Thai population. Cases comprised 18 SJS/TEN and 12 DRESS patients. This study demonstrated that genetic association of CTX-induced SCARs was phenotype-specific. HLA-B*15:02 and HLA-C*08:01 alleles were significantly associated with CTX-induced SJS/TEN, whereas the HLA-B*13:01 allele was significantly associated with CTX-induced DRESS. In addition, a significant higher frequency of HLA-A*11:01-B*15:02 and HLA-B*13:01-C*03:04 haplotypes were detected in the group of CTX-induced Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) and DRESS cases, respectively. Genetic association of CTX-induced SCARs is phenotype-specific. Interestingly, these association was observed only in HIV-infected patients but not in non-HIV-infected patients.

Reliability and validity of the Thai Drug Hypersensitivity Quality of Life Questionnaire: a multi-center study

OBJECTIVE

To adapted the Drug Hypersensitivity Quality of Life (DrHy-Q) Questionnaire from Italian into Thai and assessed its validity and reliability.

DESIGN

Prospectively recruited during January 2012-May 2017.

SETTING

Multicenter; six Thai tertiary university hospitals.

STUDY PARTICIPANTS

Total of 306 patients with physician-diagnosed drug hypersensitivity.

INTERVENTIONS

Internal consistency and test-retest reliability were evaluated among 68 participants using Cronbach's ɑ and intra-class correlation coefficient (ICC). The validity of Thai DrHy-Q was assessed among 306 participants who completed World Health Organization Quality of Life-BREF (WHOQOL-BREF-THAI). Construct and divergent validities were assessed for Thai DrHy-Q. Known-groups validity assessing discriminating ability was conducted in Thai DrHy-Q and WHOQOL-BREF-THAI.

MAIN OUTCOME MEASURES

Validity; reliability; single vs. multiple drug allergy; non-severe cutaneous adverse reactions (SCAR) vs. SCAR.

RESULTS

Thai DrHy-Q showed good reliability (Cronbach's ɑ = 0.94 and ICC = 0.8). Unidimensional factor structure was established by confirmatory factor analysis (CFI&TLI = 0.999, RMSEA = 0.02). Divergent validity was confirmed by weak correlation between Thai DrHy-Q and WHOQOL-BREF-THAI domains (Pearson's r = -0.41 to -0.19). Known-groups validity of Thai DrHy-Q was confirmed with significant difference between patients with and without life-threatening SCAR (P = 0.02) and patients with multiple implicated drug classes vs. those with one class (P < 0.01); while WHOQOL-BREF-THAI could differentiate presence of life-threatening SCAR (P < 0.01) but not multiple-drug allergy.

CONCLUSIONS

Thai DrHy-Q was reliable and valid in evaluating quality of life among patients with drug hypersensitivity. Thai DrHy-Q was able to discriminate serious drug allergy phenotypes from non-serious manifestations in clinical practice and capture more specific drug-hypersensitivity aspects than WHOQOL-BREF-THAI.

The measurement of drug-induced interferon γ-releasing cells and lymphocyte proliferation in severe cutaneous adverse reactions

BACKGROUND

The lymphocyte transformation test (LTT) is a standard laboratory method to identify culprit drugs in patients with a history of drug-induced non-immediate hypersensitivity and is mainly performed during the recovery phase. The measurement of drug-specific interferon γ (IFN-γ)-releasing cells has been introduced to confirm culprit drugs, even during the acute phase of drug allergy.

OBJECTIVES

This study aimed to evaluate the capability of the enzyme-linked immunospot assay (ELISpot) to detect drug-specific IFN-γ-releasing cells during the acute phase and the capability of LTT to identify culprit drugs during the recovery phase in patients presenting with severe cutaneous adverse reactions (SCARs).

METHODS

Peripheral blood mononuclear cells (PBMCs) from 23 SCAR patients were collected during the acute and recovery phases and assayed for drug-specific IFN-γ-releasing cells and lymphocyte proliferation, respectively.

RESULTS

Drug-specific IFN-γ-releasing cells were detectable in 73.9% of SCAR subjects (55.6% and 85.7% in patients who were and were not taking systemic steroids, respectively), whereas LTT results were positive in 52.2% of SCAR subjects. The frequencies of drug-specific IFN-γ-releasing cells were significantly higher in patients with positive LTT than in those with negative LTT (260.1 ± 110.0 and 46.6 ± 20.7 cells/10⁶ PBMCs, P = 0.01). A significant correlation between the results of the IFN-γ ELISpot assay and LTT was demonstrated (r = 0.65, P value <0.01).

CONCLUSION

The IFN-γ ELISpot assay could be a useful tool to identify culprit drugs in SCAR patients when culprit drug identification is urgently needed during the acute phase of drug allergy.

In vitro test to confirm diagnosis of allopurinol-induced severe cutaneous adverse reactions

BACKGROUND

Allopurinol is a frequent cause of severe cutaneous adverse reactions (SCARs), such as drug reaction with eosinophilia and systemic symptoms (DRESS), Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). The reactions can potentially be fatal. As drug rechallenge in patients with a history of drug-induced SCARs is contraindicated, in vitro testing may have a diagnostic role as a confirmation test.

OBJECTIVES

To study the diagnostic value of interferon (IFN)-γ enzyme-linked immunospot (ELISpot) assay as a confirmatory test in patients with a history of allopurinol-induced SCARs.

METHODS

Peripheral blood mononuclear cells (PBMCs) from 24 patients with a history of allopurinol-induced SCAR (13 DRESS, 11 SJS/TEN) and 21 control subjects were incubated with allopurinol or oxypurinol in the presence or absence of antiprogrammed death ligand 1 antibody (anti-PD-L1). The numbers of IFN-γ-releasing cells after stimulation in each group were subsequently measured with ELISpot.

RESULTS

The numbers of IFN-γ-releasing cells in allopurinol-allergic subjects were significantly higher than in control subjects when stimulating PBMCs with oxypurinol 100 μg mL^-1 , especially when adding anti-PD-L1 supplementation. According to the receiver operating characteristic curve results, the optimal discriminatory power of IFN-γ ELISpot in confirming diagnosis of allopurinol-induced SCARs can be obtained using 16 spot-forming cells per 10⁶ PBMCs as a cut-off value upon oxypurinol/anti-PD-L1 stimulation (79·2% sensitivity and 95·2% specificity).

CONCLUSIONS

The measurement of oxypurinol/anti-PD-L1-inducing IFN-γ-releasing cells yields a high diagnostic value in distinguishing between allopurinol-allergic and control subjects. This technique is beneficial in confirming diagnosis of allopurinol-induced SCARs in patients whose reaction develops while taking multiple drugs.

Adverse events associated with mohs micrographic surgery: multicenter prospective cohort study of 20,821 cases at 23 centers

IMPORTANCE

Detailed information regarding perioperative risk and adverse events associated with Mohs micrographic surgery (MMS) can guide clinical management. Much of the data regarding complications of MMS are anecdotal or report findings from single centers or single events.

OBJECTIVES

To quantify adverse events associated with MMS and detect differences relevant to safety.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter prospective inception cohort study of 21 private and 2 institutional US ambulatory referral centers for MMS. Participants were a consecutive sample of patients presenting with MMS for 35 weeks at each center, with staggered start times.

EXPOSURE

Mohs micrographic surgery. MAIN OUTCOMES AND MEASURES Intraoperative and postoperative minor and serious adverse events.

RESULTS

Among 20 821 MMS procedures, 149 adverse events (0.72%), including 4 serious events (0.02%), and no deaths were reported. Common adverse events reported were infections (61.1%), dehiscence and partial or full necrosis (20.1%), and bleeding and hematoma (15.4%). Most bleeding and wound-healing complications occurred in patients receiving anticoagulation therapy. Use of some antiseptics and antibiotics and sterile gloves during MMS were associated with modest reduction of risk for adverse events.

CONCLUSIONS AND RELEVANCE

Mohs micrographic surgery is safe, with a very low rate of adverse events, an exceedingly low rate of serious adverse events, and an undetectable mortality rate. Common complications include infections, followed by impaired wound healing and bleeding. Bleeding and wound-healing issues are often associated with preexisting anticoagulation therapy, which is nonetheless managed safely during MMS. We are not certain whether the small effects seen with the use of sterile gloves and antiseptics and antibiotics are clinically significant and whether wide-scale practice changes would be cost-effective given the small risk reductions.

Topical tacrolimus significantly promotes repigmentation in idiopathic guttate hypomelanosis: a double-blind, randomized, placebo-controlled study

BACKGROUND

Idiopathic guttate hypomelanosis (IGH) is an idiopathic disorder affecting a large number of people. Effective treatments are not yet available. Objectives To investigate the efficacy of topical 0.1% tacrolimus ointment compared with placebo in the treatment of IGH.

MATERIALS AND METHODS

Twenty-six patients were included in the study. Lesions on one side of the body were selected to have a treatment with 0.1% tacrolimus ointment, whereas those on the other side served as a control with placebo ointment that had the same physical appearance. Colorimeter was used to assess skin colour at baseline and at 1, 2, 3, 4 and 6 months of treatment.

RESULTS

Mean luminosity scale after adjusted for baseline from the treated side gradually decreased and reached statistical significance compared with the control group after 6 months of treatment (P = 0.019). Physicians' improvement grading score showed that 11% of the patients demonstrated improvement of their skin lesions on the treated side after 6 months' treatment.

CONCLUSION

Topical 0.1% tacrolimus ointment appeared to be an effective and safe treatment for IGH. The improvements were best observed by colorimetry, yet, they were not statistically significant upon clinical assessments.

Contact allergy in eczema patients in Thammasat University Hospital

Many patients with eczematous dermatitis need continued care in case of a recurrent or persistent skin condition and potential adverse effect of medications. Allergic contact dermatitis should be considered in the differential diagnosis of eczematous dermatitis especially in a patient whose dermatitis is persistent despite appropriate therapies. Patch testing is an essential investigation in patients with persistent eczematous eruption when contact allergy cannot be ruled out. The purpose of this study was to determine the frequency of contact allergy in patients with eczematous dermatitis in Thammasat University Hospital, Prathumthani, Thailand from June 1, 2008 to June 30, 2009 and to identify a possible relationship between sex, age, occupational differences and type of eczema that is associated with positive patch test reactions. A total of 157 patients were patch tested with 23 standard allergens. One or more positive responses were noted in 70 patients (44.6%). The most common allergen was nickel sulfate (26.8%), followed by cobalt chloride (7.6%), p-phenylenediamine (7.0%), fragrance mix (7.0%). Patients who were initially diagnosed with allergic contact dermatitis had significant correlation with positive patch test results to nickel sulfate, cobalt chloride and phenylenediamine (p = 0.00, p = 0.03, p = 0.02, respectively). Patients who were initially diagnosed with endogenous eczema had significant correlation with positive patch test results to colophony (p = 0.04). Contact allergy to fragrance mix was significantly more frequent in patients who had personal history of atopy (p = 0.04). There was no significant correlation between the frequency of contact allergy and sex, age, location of lesion and patient's occupation. In conclusion, this study demonstrated the prevalence in contact allergy in eczema patients in Thammasat University Hospital and compared the results with other region from Thailand. Further study involving many hospitals in various areas in Thailand is needed to provide more insight into contact allergy in Thailand.