Delayed Drug Hypersensitivity Reactions: Molecular Recognition, Genetic Susceptibility, and Immune Mediators

Eco-friendly antibacterial electrospinning nanofibrous film containing nano-silver green-synthesized by natural glycoprotein for infected wound healing

Infected wounds caused by bacteria commonly cause delayed wound healing and even serious tissue damage, evolving into one of the most problematic clinical issues. Traditional therapies and wound dressings cannot achieve either the ideal antibiotic activity or the accelerated wound healing outcomes. Based on our previous finding that glycoproteins (PAGP) derived from medicinal animal insect Periplaneta americana L. have a significant promoting effect on wound healing, herein we primarily prepared the silver nanoparticles (Ag NPs) by the facile green-synthesis mediated by PAGP, and then the eco-friendly PAGP nanofibrous film inlaid with Ag NPs (Ag NPs@PP film) was fabricated by electrospinning. The obtained nanofibrous dressing had good mechanical properties, surface wettability, biocompatibility, and antibacterial properties. Compared with nanofiber film containing only Ag NPs or PAGP, the Ag NPs@PP film had stronger abilities to promote the M2 polarization of macrophages and higher wound-healing efficacy on fecal bacteria-infected wounds. To sum up, this nanofibrous film held great promise to improve the healing of infected wounds.

Diagnosing and Managing Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis in Adults: Review of Evidence 2017-2023

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening reactions associated with long-term disabling sequelae. In the acute phase, the best supportive care in expert centers is the cornerstone of treatment. The follow-up is prolonged and multidisciplinary, according to the patient's needs. In this paper, we review the evidence from 2017 to 2023 for the diagnosis and management of SJS/TEN in adults. On the basis of this review and our own experience, we present recommendations for the diagnosis of SJS/TEN in adults, management in the acute phase (best supportive care; prevention of infections; skin, ocular, and other mucosa management; intensive care measures; and etiological treatment), and follow-up. The most frequent sequelae are cutaneous, ocular, and psychological. High-quality studies assessing the efficacy of immunomodulating agents (eg, cyclosporine, corticosteroids, intravenous Igs, and anti-TNF agents) in accelerating healing and reducing mortality are still lacking. In addition, we propose avenues for future studies.

Generation of frameshift-mutated TGFβR2-specific T cells in healthy subjects following administration with cancer vaccine candidate FMPV-1/GM-CSF in a phase 1 study

FMPV-1 is a component of FMPV-3, an investigational cancer-specific vaccine and being developed to activate anti-cancer T cell responses targeting frameshift mutations of MSI-H cancers. FMPV-1 is designed to activate T cell responses against transforming growth factor β receptor 2 (TGFβR2) frameshift mutation. Microsatellite instability high (MSI-H) gastrointestinal cancers frequently harbour TGFβR2 frameshift mutations. This first-in-human, phase 1, single centre, open-label study included 16 healthy male subjects who received FMPV-1 (0.15 mg/injection) plus granulocyte-macrophage colony-stimulating factor (GM-CSF) (0.03 mg/injection) as two separate, co-located, injections on Days 1, 8, 15, 29 and 43. All subjects were followed to Day 365. A FMPV-1-specific delayed type hypersensitivity (DTH) skin reactivity test was performed with FMPV-1 (without GM-CSF) on Days 1, 29 and 43 with assessment after 2 days. All subjects were DTH negative at baseline, 8/16 were positive on Day 31 and 15/16 were positive on Day 45. Furthermore, the FMPV-1/GM-CSF induced frameshift mutant TGFβR2-specific T cells after the short vaccination period, and specific T cells were still detectable after 6 and 12 months indicating induction of frameshift mutant TGFβR2-specific T memory cells. Adverse events were limited to mild injection site reactions with no evidence of related systemic signs or symptoms. No other clinically important changes to vital signs, electrocardiograms, haematological, coagulation or laboratory measures related to treatment were observed. FMPV-1/GM-CSF was well tolerated and generated vaccine-specific T cell immune responses in healthy subjects. These findings support clinical studies in patients with, or at risk of, cancers carrying TGFβR2 frameshift mutations.Clinical trial identification: ClinicalTrials.gov: NCT05238558. EudraCT: 2020-004363-80.

A comprehensive update on the human leukocyte antigen and idiosyncratic adverse drug reactions

INTRODUCTION

Idiosyncratic adverse drug reactions (IADRs) or drug hypersensitivity reactions (DHRs) represent a major health problem because they are unpredictable and can be severe with potential life-long or even lethal consequences. Their pathophysiology is not clear but thought to be immune mediated, supported by the significant statistical association of these reactions with specific alleles of the human leukocyte antigen (HLA) gene.

AREA COVERED

This comprehensive update review summarizes the currently available evidence on the role of HLA gene locus in IADRs and discusses the present understanding of the pathophysiology of IADRs. We searched the available literature in PubMed and Google Scholar with no date restriction for publications on HLA and adverse drug reactions. Findings are summarized and discussed in the context of the currently available evidence.

EXPERT OPINION

The role of the immune system in IADRs and the role of pharmacogenetic testing in this field is evident. HLA genetic testing is very promising in the management of these reactions. Many obstacles seem to prevent pharmacogenetic testing to meet its full potential including cost and health care providers' education. Further work in needed to provide more evidence and allow widespread use of pharmacogenetic testing in the clinical practice.

DRESS syndrome: an interaction between drugs, latent viruses, and the immune system

Drug-induced hypersensitivity syndrome, also known as DRESS syndrome, is a serious and potentially fatal reaction that occurs in response to prolonged use (generally between 14 and 60 days) of certain drugs, and which has no predilection for gender or age group. It is believed that DRESS syndrome has a genetic basis and results from the interaction between metabolites of certain pharmacological groups, reactivation of latent viruses (especially from the Herpesviridae family), and a cellular immune response. The classic manifestation of DRESS syndrome includes a generalized rash accompanied by fever, eosinophilia, lymphadenopathy, and systemic involvement such as hepatitis, nephritis, or pneumonitis. With the continuous increase in the availability of drugs and the aging of the population, there is a favorable scenario for the development of adverse drug reactions. Physicians should be prepared for the early diagnosis of DRESS syndrome, the identification and immediate suspension of the drug involved, and also manage systemic involvement, which may require prolonged immunosuppressive therapy. This article provides an update on the clinical, physiopathological and therapeutic aspects of DRESS syndrome.

Exploring recent advances in drugs severe cutaneous adverse reactions immunopathology

Severe cutaneous adverse reactions to drugs (SCARs) are rare but life-threatening delayed allergies. While they primarily affect the skin, they can also affect internal organs. Accordingly, they present with diverse clinical symptoms that vary not only between SCARs subtypes but also among patients. Despite the availability of topical and systemic treatments, these only address the symptoms and not the cause. To develop more effective therapies, it is necessary to elucidate the complexity of the pathophysiology of SCARs in relation to their severity. In line with the new type IV hypersensitivity reactions nomenclature proposed by the European Academy of Allergy and Clinical Immunology (EAACI), this review highlights the current insights into the intricate immune mechanisms engaged, the interplay between the culprit drug and genetic predisposition in drug presentation mechanisms, but also how external factors, such as viruses, are implicated in SCARs. Their relevance to the development of targeted medicine is also discussed.

Immune Checkpoint Inhibitor-Associated Cutaneous Adverse Events: Mechanisms of Occurrence

Immunotherapy, particularly that based on blocking checkpoint proteins in many tumors, including melanoma, Merkel cell carcinoma, non-small cell lung cancer (NSCLC), triple-negative breast (TNB cancer), renal cancer, and gastrointestinal and endometrial neoplasms, is a therapeutic alternative to chemotherapy. Immune checkpoint inhibitor (ICI)-based therapies have the potential to target different pathways leading to the destruction of cancer cells. Although ICIs are an effective treatment strategy for patients with highly immune-infiltrated cancers, the development of different adverse effects including cutaneous adverse effects during and after the treatment with ICIs is common. ICI-associated cutaneous adverse effects include mostly inflammatory and bullous dermatoses, as well as severe cutaneous side reactions such as rash or inflammatory dermatitis encompassing erythema multiforme; lichenoid, eczematous, psoriasiform, and morbilliform lesions; and palmoplantar erythrodysesthesia. The development of immunotherapy-related adverse effects is a consequence of ICIs' unique molecular action that is mainly mediated by the activation of cytotoxic CD4+/CD8+ T cells. ICI-associated cutaneous disorders are the most prevalent effects induced in response to anti-programmed cell death 1 (PD-1), anti-cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), and anti-programmed cell death ligand 1 (PD-L1) agents. Herein, we will elucidate the mechanisms regulating the occurrence of cutaneous adverse effects following treatment with ICIs.

Pediatric dermatologic emergencies

PURPOSE OF REVIEW

Provide an overview of recent findings and recommendations for the presentation, diagnosis, and management of pediatric dermatologic emergencies.

RECENT FINDINGS

Updated information on optimal diagnosis and treatments for pediatric dermatologic emergencies because of infection, reactive infectious mucocutaneous eruption, and serious cutaneous adverse reactions are covered.

SUMMARY

Pediatric dermatologic emergencies require prompt diagnosis and management. This review covers new agents and techniques for management and 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.

Drug-induced hypersensitivity syndrome related to piperacillin-tazobactam: a case report and review of the literature

Allergic reactions to drugs caused by piperacillin-tazobactam are common in clinical practice. However, we also found a few cases of drug-induced hypersensitivity syndrome (DiHS)/Drug reaction with eosinophilia and systemic symptoms (DRESS) caused by piperacillin-tazobactam in our clinical work. We report a case of a 60-year-old female patient who was treated with piperacillin-tazobactam anti-infective therapy after the diagnosis of hematogenous lung abscess, developed fever, rash, and blood abnormalities after 26 days of application, and was later diagnosed as DIHS, which was improved after the administration of glucocorticoid and anti-allergic drugs. In addition, we also retrospectively analyzed 17 cases of DiHS caused by piperacillin-tazobactam from the PubMed databases between March 1980 and September 2023. The majority of the patients had an incubation period of more than 14 days, and the common clinical features included elevated eosinophil count/percentage, fever, rash, liver damage, and lymph node enlargement. After treatment with topical or systemic glucocorticoids, 16 of the 17 patients improved and one died because of the underlying condition. The clinical features of DiHS were diverse and included a long incubation period, skin rash, elevated eosinophils, and impaired organ function. Since some patients have atypical clinical features, clinicians should raise awareness of the disease, recognize these features early, and treat them promptly.

Molecular Mechanisms of Cutaneous Immune-Related Adverse Events (irAEs) Induced by Immune Checkpoint Inhibitors

Over the past few decades, immune checkpoint inhibitors (ICIs) have emerged as promising therapeutic options for the treatment of various cancers. These novel treatments effectively target key mediators of immune checkpoint pathways. Currently, ICIs primarily consist of monoclonal antibodies that specifically block cytotoxic T-lymphocyte antigen 4 (CTLA-4), programmed cell death 1 (PD-1), programmed cell death-ligand 1 (PD-L1), and lymphocyte activation gene 3 protein (LAG-3). Despite the notable efficacy of ICIs in cancer treatment, they can also trigger immune-related adverse events (irAEs), which present as autoimmune-like or inflammatory conditions. IrAEs have the potential to affect multiple organ systems, with cutaneous toxicities being the most commonly observed. Although cutaneous irAEs are typically of low-grade severity and can usually be managed effectively, there are cases where severe irAEs can become life-threatening. Therefore, early recognition and a comprehensive understanding of the mechanisms underlying cutaneous irAEs are crucial for improving clinical outcomes in cancer patients. However, the precise pathogenesis of cutaneous irAEs remains unclear. This review focuses on the skin manifestations induced by ICIs, the prognosis related to cutaneous irAEs, and the exploration of potential mechanisms involved in cutaneous irAEs.