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

Latin American guidelines for the diagnosis and treatment of Stevens-Johnson syndrome and toxic epidermal necrolysis

Background

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe cutaneous reactions induced by delayed drug hypersensitivity, characterized by their complexity and multisystemic nature. Their diagnosis and management are challenging and require a multidisciplinary approach. Identifying the culprit drug is crucial to ensure that the patient has access to safe therapeutic options in the future. To date, there are no specific Latin American guideline or consensus documents on SJS/TEN.

Objective

To develop a Latin American guideline on the clinical diagnosis, management, and treatment of SJS/TEN, based on available scientific evidence and the experience of experts from various medical specialties.

Methods

This guideline was developed by a group of Latin American allergists and dermatologists involved in the management of SJS/TEN. A search of scientific publications was conducted, and the expert group evaluated the available evidence in the literature, providing grades of recommendation. In cases where there was insufficient evidence, consensus was reached among the experts.

Results

The Latin American guidelines on SJS/TEN were developed, addressing relevant practical aspects of clinical diagnosis, and the identification of culprit drugs using the ALDEN (Algorithm of Drug Causality for Epidermal Necrolysis). It also offers recommendations on management, treatment, and prevention of complications, along with a specific algorithm for disease management. This guideline includes a therapeutic strategy, developed and agreed upon by expert specialists involved in the treatment of SJS/TEN.

Outcomes of pediatric patients with suspected allergies to COVID-19 vaccines

Background

Adverse effects following immunizations (AEFIs) can contribute to vaccine hesitancy.

Objective

We evaluated clinical outcomes of AEFIs subsequent to administration of the coronavirus disease 2019 (COVID-19) vaccine at 2 pediatric allergy centers.

Methods

Data on pediatric patients referred for COVID-19 AEFI concerns between March 2021 and October 2022 were reviewed. The collected data included patient demographics, clinical characteristics, outcomes of prior COVID-19 vaccination, recommendations after consultation, and outcomes of revaccination.

Results

The 163 patients were separated into 2 groups based on the absence (n = 89 [54.6%]) or presence (n = 74 [45.4%]) of prior COVID-19-related AEFIs. The most common reason for referral without a prior AEFI was another suspected drug allergy (n = 58 [35.6%]). All patients in this group were recommended for COVID-19 vaccination. Of the 163 patients, 82 (92.1%) proceeded with vaccination, with 77 of them (93.9%) tolerating vaccination. Most of those with a prior COVID-19-related AEFI had a delayed cutaneous reaction (n = 60 [37.0%]); 1 patient (0.6%) had suspected anaphylaxis. In this group, 6 (8.1%) were advised to postpone COVID-19 vaccination until their debilitating skin conditions had improved in response to further treatment, whereas 45 (77.6%) tolerated subsequent vaccination to the same or an alternate COVID-19 vaccine type. The most common AEFI on revaccination was urticaria (in 8 of 11 patients [72.7%]). AEFI on revaccination was significantly associated with a history of spontaneous urticaria or angioedema (relative risk = 3.6 [95% CI = 1.30-9.99]; P = .020) and urticaria following COVID-19 vaccination previously (relative risk = 4.12 [95% CI = 1.22-13.87]; P = .017).

Conclusions

Children with a history of urticaria or angioedema related or unrelated to prior COVID-19 vaccination were at higher risk of a COVID-19-related AEFI on revaccination, although most were able to complete the vaccination series under the management of our immunology/allergy service.

Pseudoephedrine-induced Fixed Drug Eruption in a Scuba Diver With Recurrent Palmoplantar Exfoliation

This report presents a case of pseudoephedrine-induced non-pigmented bullous fixed drug eruption (NBFDE) manifesting as recurrent palmoplantar exfoliation in a scuba diver. It emphasizes the importance of considering drug allergies in the differential diagnosis when divers present with peeling hands and soles. A 38-year-old female scuba diver experiencing recurrent palmoplantar exfoliation underwent a clinical evaluation, patch testing, an interferon-gamma enzyme-linked immunospot (ELISpot) assay, and graded drug challenges with pseudoephedrine and phenylephrine. Patch testing yielded negative results; however, the ELISpot assay indicated a strong immune response to pseudoephedrine. A graded challenge involving pseudoephedrine successfully reproduced the symptoms, confirming a diagnosis of pseudoephedrine-induced NBFDE. Subsequently, a challenge with phenylephrine elicited a milder reaction, suggesting it as a potential alternative medication for the patient. This case highlights NBFDE as a potential cause of skin peeling in scuba divers who are allergic to pseudoephedrine. It emphasizes the importance of considering drug allergies when diagnosing palmoplantar exfoliation in divers and underscores the need for a thorough evaluation of medication use in this group. Alternative medications and management strategies should be considered for divers with a pseudoephedrine allergy to prevent ear barotrauma while minimizing the risk of adverse skin reactions.

Development and validation of a clinical prediction model for osteonecrosis of the jaw in patients receiving zoledronic acid using FAERS and canadian databases

Background

Osteonecrosis of the jaw (ONJ) stands as a severe complication linked to the use of bisphosphonates, particularly zoledronic acid, which is widely prescribed for managing conditions like osteoporosis and bone metastasis. This study is geared towards the development and validation of a clinical prediction model for ONJ in patients undergoing zoledronic acid treatment.

Methods

We harnessed data from the FDA Adverse Event Reporting System (FAERS) as our training dataset, while the Canada Vigilance Adverse Reaction (CVAR) database served as the testing dataset. The study encompassed patients treated with zoledronic acid and subsequently diagnosed with ONJ. We analysed a range of predictive factors, including breast cancer, bone metastasis, osteoporosis, vitamin D and calcium levels, comorbidities, the number of concomitant medications, dosage, age, weight, and gender. Logistic regression and nomogram analysis were the chosen methodologies for constructing the predictive model. To evaluate the model's performance, we utilized receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA).

Results

The study encompassed a total of 2,126 patients in the training cohort, 911 patients in the internal test cohort from the FAERS database, and 121 patients in the external test cohort from the CVAR database. Notable predictors for ONJ included bone metastasis (OR: 1.65, 95% CI: 1.22-2.24), osteoporosis (OR: 0.33, 95% CI: 0.21-0.52), the number of concomitant medications (OR: 1.07, 95% CI: 1.05-1.09), and the dosage of zoledronic acid (OR: 1.24, 95% CI: 1.10-1.39). The nomogram exhibited robust discriminatory power, evidenced by an area under the curve (AUC) of 0.77 in the training cohort, 0.76 in the internal test cohort, and 0.90 in the external test cohort. Calibration plots demonstrated a strong alignment between observed and predicted probabilities. Furthermore, DCA highlighted the prediction model's significant net benefit across various threshold probabilities.

Conclusion

By leveraging data from both the FAERS and Canadian databases, this study has successfully developed and validated a clinical prediction model for ONJ in patients receiving zoledronic acid. This model stands as a valuable tool for clinicians, enabling them to pinpoint high-risk patients and make evidence-based treatment decisions to minimize the risk of ONJ.

The Australasian Registry for Severe Cutaneous Adverse Reactions (AUS-SCAR) - Providing a roadmap for closing the diagnostic, patient, and healthcare gaps for a group of rare drug eruptions

Background

Severe cutaneous adverse reactions (SCAR) are a group of delayed presumed T-cell mediated hypersensitivities associated with significant morbidity and mortality. Despite their shared global healthcare burden and impact, the clinical phenotypes, genomic predisposition, drug causality, and treatment outcomes may vary. We describe the establishment and results from the first Australasian registry for SCAR (AUS-SCAR), that via a collaborative network advances strategies for the prevention, diagnosis and treatment of SCAR.

Methods

Prospective multi-center registry of SCAR in Australian adult and adolescents, with planned regional expansion. The registry collects externally verified phenotypic data drug causality, therapeutics and long-term patient outcomes. In addition, biorepository specimens and DNA are collected at participating sites.

Results

we report on the first 100 patients enrolled in the AUS-SCAR database. DRESS (50%) is the most predominant phenotype followed by SJS/TEN (39%) and AGEP (10%), with median age of 52 years old (IQR 37.5, 66) with 1:1 male-to-female ratio. The median latency for all implicated drugs is highly variable but similar for DRESS (median 15 days IQR 5,25) and SJS/TEN (median 21 days, IQR 7,27), while lowest for AGEP (median 2.5 days, IQR 1,8). Antibiotics (54.5%) are more commonly listed as primary implicated drug compare with non-antibiotics agent (45.5%). Mortality rate at 90 days was highest in SJS/TEN at 23.1%, followed by DRESS (4%) and AGEP (0%).

Conclusion

In the first prospective national phenotypic and biorepository of SCAR in the southern hemisphere we demonstrate notable differences to other reported registries; including DRESS-predominant phenotype, varied antibiotic causality and low overall mortality rate. This study also highlights the lack of standardised preventative pharmacogenomic measures and in vitro/in vivo diagnostic strategies to ascertain drug causality.

Trial registration

ANZCTR ACTRN12619000241134. Registered 19 February 2019.

Predictive models and applicability of artificial intelligence-based approaches in drug allergy

PURPOSE OF REVIEW

Drug allergy is responsible for a huge burden on public healthcare systems, representing in some instances a threat for patient's life. Diagnosis is complex due to the heterogeneity of clinical phenotypes and mechanisms involved, the limitations of in vitro tests, and the associated risk to in vivo tests. Predictive models, including those using recent advances in artificial intelligence, may circumvent these drawbacks, leading to an appropriate classification of patients and improving their management in clinical settings.

RECENT FINDINGS

Scores and predictive models to assess drug allergy development, including patient risk stratification, are scarce and usually apply logistic regression analysis. Over recent years, different methods encompassed under the general umbrella of artificial intelligence, including machine and deep learning, and artificial neural networks, are emerging as powerful tools to provide reliable and optimal models for clinical diagnosis, prediction, and precision medicine in different types of drug allergy.

SUMMARY

This review provides general concepts and current evidence supporting the potential utility of predictive models and artificial intelligence branches in drug allergy diagnosis.

Severe cutaneous adverse reactions

Severe cutaneous adverse reactions (SCARs), which include Stevens-Johnson syndrome and toxic epidermal necrolysis, drug reaction with eosinophilia and systemic symptoms (also known as drug-induced hypersensitivity syndrome), acute generalized exanthematous pustulosis, and generalized bullous fixed drug eruption, are life-threatening conditions. The pathogenesis of SCARs involves T cell receptors recognizing drug antigens presented by human leukocyte antigens, triggering the activation of distinct T cell subsets. These cells interact with keratinocytes and various immune cells, orchestrating cutaneous lesions and systemic manifestations. Genetic predisposition, impaired drug metabolism, viral reactivation or infections, and heterologous immunity influence SCAR development and clinical presentation. Specific genetic associations with distinct SCAR phenotypes have been identified, leading to the implementation of genetic screening before prescription in various countries to prevent SCARs. Whilst systemic corticosteroids and conventional immunomodulators have been the primary therapeutic agents, evolving strategies, including biologics and small molecules targeting tumour necrosis factor, different cytokines, or Janus kinase signalling pathways, signify a shift towards a precision management paradigm that considers individual clinical presentations.

Omeprazole Induced Rapid Drug Reaction with Eosinophilia, Systemic Symptoms, and Cross-Reactivity in Delayed-Type Hypersensitivity Associated with Proton-Pump Inhibitors: A Case Report and Literature Review

Background

Omeprazole, a proton pump inhibitor (PPI), is a widely used and generally safe agent for treating acid-related gastrointestinal conditions. However, drug reaction with eosinophilia and systemic symptoms (DRESSs) syndrome has been reported.

Objectives

To report a case of omeprazole-induced rapid DRESS syndrome and to review the literature.

Methods

Descriptive analysis of one new case and a case series from literature review.

Results

We report a case of 82-year-old woman presenting with rapid-onset of DRESS syndrome. The condition was initially suspected to be caused by antibiotic, but the definite diagnosis was eventually omeprazole-induced DRESS syndrome as suggested by the enzyme-linked immune absorbent spot (ELISpot) assay along with the clinical picture. Previous literatures regarding cases of PPI-induced DRESS syndrome were pooled for descriptive analysis. Among 21 PPI cases pooled, esomeprazole was the most commonly implicated PPI (52.4%), followed by pantoprazole (19.1%), and omeprazole along with lansoprazole (both 14.3%). The issue of cross-reactivities amongst PPIs remains uncertain. Nonetheless, in situations in which a PPIs are deemed necessary, a prudent approach could be considering a switch to an alternative agent with distinct chemical structure.

Conclusion

PPI is commonly used safely as an agent for acid-related gastrointestinal conditions. However, PPI-induced rapid DRESS syndrome can occur, particularly with prior exposure history. ELISpot is an in vitro test, useful in identifying the culprit agent in patients with delayed-type hypersensitivity reaction.