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.

Recognizing rare rashes: A case of acute generalized exanthematous pustulosis.

ABSTRACT: Acute generalized exanthematous pustulosis (AGEP) is a rare, pustular rash that occurs most commonly after exposure to a medication (typically antibiotics or diltiazem). This case describes a patient who developed a widespread pustular eruption shortly after beginning empiric antibiotics for community-acquired pneumonia. Diagnosis of AGEP was difficult in this scenario due to the patient's pulmonary infection and atypical skin biopsy results. However, after AGEP was correctly identified, the offending agents were discontinued and the patient had subsequent resolution of her symptoms.

Severe cutaneous adverse reactions associated with the immune checkpoint inhibitors: A case/non-case analysis using the Food and Drug Administration Adverse Event Reporting System.

BACKGROUND/OBJECTIVES: The immune checkpoint inhibitors (ICIs) have been increasingly associated with severe cutaneous adverse reactions (SCARs). These reactions, including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS) and acute generalized exanthematous pustulosis (AGEP) are uncommon but potentially lethal. Despite the severity of these reactions and growing association with the ICIs, their specific risk and mortality rates have been largely unexplored. METHODS: A case/non-case analysis was performed using data from the United States Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) to examine the reporting odds ratios (RORs) for ICI-associated SCARs cases under two conditions: (1) ICIs compared with all drugs in FAERS and (2) ICIs compared with a reference group of pooled anticancer drugs to control for underlying malignancy. RESULTS: A statistically significant ROR for SJS (ROR: 5.44), TEN (ROR: 5.81) and DRESS (ROR: 1.38) were identified under Condition 1. Under Condition 2, this significance was maintained for SJS (ROR: 7.31), TEN (ROR: 7.40) and DRESS (ROR: 3.90), and mild significance was identified for AGEP (ROR: 1.89). Mortality rates for the ICIs were increased compared with the anticancer medications (28.5% vs. 24.5% for SJS, 55.3% vs. 46% for TEN, 3.0% vs. 2.1% for AGEP and 7.1% vs. 6.1% for DRESS). CONCLUSIONS: Our results suggest an association between SCARs and the ICIs independent of cancer status.

Generalized Pustular Psoriasis, Acute Generalized Exanthematous Pustulosis, and Other Pustular Reactions: A Clinical Review.

Generalized pustular rashes have various etiologies and can be challenging to diagnose and manage at first presentation. The authors provide an in-depth analysis of common pustular skin eruptions including generalized pustular psoriasis (GPP) and acute generalized exanthematous pustulosis, focusing on their pathophysiology, triggers, clinical presentation, diagnostic challenges, and management strategies. The article also highlights recent advances in genetic research and biologic therapies for GPP and the future directions in personalized medicine and prevention strategies.

Medication Associations With Severe Cutaneous Adverse Reactions: A Case/Non-Case Analysis Using the FDA Adverse Event Reporting System.

BACKGROUND: Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS), and acute generalized exanthematous pustulosis (AGEP) are potentially life-threatening severe cutaneous adverse reactions (SCARs). Although the classical causal agents of SCARs (antibiotics, anticonvulsants, nonsteroidal anti-inflammatory drugs, and allopurinol) are well characterized, there has been little update to this list to account for newly marketed medications. OBJECTIVE: To provide an updated and stratified list of medications with significant reporting odds ratios (RORs) of SCARs. METHODS: A case/non-case analysis using the United States FDA Adverse Event Reporting System was performed. RESULTS: As expected, the prototypical medication classes made up the majority of reported cases of SJS, TEN, AGEP, and DRESS (77%, 64%, 75%, and 72%, respectively). In addition, several infrequently or previously undescribed classes/medications implicated in SCARs were identified to have significant ROR signals, including acetylcysteine, anticoagulants, diuretics, immunotherapies, proton pump inhibitors, antivirals, and antifungals. Among these reported for SJS were acetylcysteine (ROR: 64.38) and fluconazole (ROR: 17.13). For TEN, we identified furosemide (ROR: 26.32), spironolactone (ROR: 14.45), fluconazole (ROR: 30.21), amphotericin B (39.06), and acetylcysteine (ROR: 93.12). For AGEP, we identified acyclovir (ROR: 61.72), valacyclovir (ROR: 30.76), and enoxaparin (ROR: 27.37). For DRESS, we identified vemurafenib (ROR: 17.35), acyclovir (ROR: 30.63), abacavir (ROR: 26.62), raltegravir (ROR: 23.27), and valacyclovir (ROR: 21.77) to have strong reporting odds. CONCLUSION: Our analysis provides an updated tool for physicians to reference when identifying suspected SCARs and a basis for future studies to investigate atypical medication causality.

Acquired cutis laxa secondary to acute generalized exanthematous pustulosis: A case report and mini-review of literature.

Cutis laxa presents as loose redundant skin folds and loss of dermal elastic tissue. Acquired cutis laxa (ACL) is characterized by later onset. It has been reported in association with various kinds of neutrophilic dermatoses, drugs, metabolic disorders, and autoimmune disorders. Acute generalized exanthematous pustulosis (AGEP) is usually classified as a severe cutaneous adverse reaction characterized by T cell-mediated neutrophilic inflammation. We previously reported a mild case of AGEP caused by gemcitabine in a 76-year-old man. Here, we report a case of ACL secondary to AGEP in this patient. He developed AGEP 8 days after gemcitabine administration. Four weeks after beginning chemotherapy, his skin had become atrophic, loose, and darkly pigmented in areas previously affected by AGEP. Histopathological examination revealed edema and perivascular lymphocytic infiltration but no neutrophilic infiltration in the upper dermis. Elastica van Gieson staining showed that the elastic fibers in all layers of the dermis were sparse and shortened. Electron microscopy showed elevated numbers of fibroblasts and altered elastic fibers with irregular surfaces. Finally, he was diagnosed with ACL secondary to AGEP. He was treated with topical corticosteroids and oral antihistamines. Skin atrophy decreased over 3 months. We summarize 36 cases (including our case) with ACL secondary to neutrophilic dermatosis. We discuss these clinical manifestations, causative neutrophilic disorders, treatments, and outcomes. The mean age of patients was 3.5 years. Five patients had an aortic lesion as systemic involvement. The most common causative neutrophilic disorders were Sweet syndrome (24 cases), followed by urticaria-like neutrophilic dermatosis (11 cases). There were no cases of AGEP except for our case. Although treatment for ACL secondary to neutrophilic dermatosis, such as dapsone, oral prednisolone, adalimumab, and plastic surgery were reported, ACL is generally refractory and irreversible. Our patient was considered reversibly cured due to the absence of continuous neutrophil-mediated elastolysis.

Cutaneous adverse drug reactions.

Cutaneous adverse drug reactions (ADRs) represent a heterogeneous field including various clinical patterns without specific features suggesting drug causality. Maculopapular exanthema and urticaria are the most common types of cutaneous ADR. Serious cutaneous ADRs, which may cause permanent sequelae or have fatal outcome, may represent 2% of all cutaneous ADR and must be quickly identified to guide their management. These serious reactions include bullous manifestations (epidermal necrolysis i.e. Stevens-Johnson syndrome and toxic epidermal necrolysis), drug reaction with eosinophilia and systemic symptoms (DRESS) and acute generalized exanthematous pustulosis (AGEP). Some risk factors for developing cutaneous ADRs have been identified, including immunosuppression, autoimmunity or genetic variants. All drugs can cause cutaneous ADRs, the most commonly implicated being antibiotics (especially aminopenicillins and sulfonamides), anticonvulsants, allopurinol, antineoplastic drugs, non-steroidal anti-inflammatory drugs and iodinated contrast media. Pathophysiology is related to immediate or delayed "idiosyncratic" immunologic mechanisms, i.e., usually not related to dose, and pharmacologic/toxic mechanisms, commonly dose-dependent and/or time-dependent. If an immuno-allergic mechanism is suspected, allergological explorations (including epicutaneous patch testing and/or intradermal test) are often possible to clarify drug causality, however these have a variable sensitivity according to the drug and to the ADR type. No in vivo or in vitro test can consistently confirm the drug causality. To determine the origin of a rash, a logical approach based on clinical characteristics, chronologic factors and elimination of differential diagnosis (especially infectious etiologies) is required, completed with a literature search. Reporting to pharmacovigilance system is therefore essential both to analyze drug causality at individual level, and to contribute to knowledge of the drug at population level, especially for serious cutaneous ADRs or in cases involving newly marketed drugs.

Acute generalized exanthematous pustulosis caused by hydroxychloroquine in a patient with rheumatoid arthritis and CARD14 mutation: Case report.

RATIONALE: Acute generalized exanthematous pustulosis (AGEP) is a serious adverse skin reaction characterized by the rapid appearance of densely distributed, small, sterile pustules with erythema. However, its pathogenesis is not fully understood. Hydroxychloroquine is widely used for the treatment of autoimmune diseases. Some patients presenting with AGEP have IL36RN and CARD14 gene mutations. Our report describes a patient with rheumatoid arthritis and AGEP associated with hydroxychloroquine and a newly discovered CARD14 gene mutation. PATIENT CONCERNS: A 28-year-old woman with rheumatoid arthritis, treated with leflunomide therapy without marked relief of joint pain, developed multiple rashes with pruritis covering the body 5 days after switching to hydroxychloroquine treatment. DIAGNOSES: Based on the patient's history, symptoms, and histopathological findings, AGEP was diagnosed. INTERVENTIONS: Whole-exome sequencing and Sanger validation revealed no mutations in the IL36RN gene; however, a CARD14 gene mutation was present. The patient was treated using ketotifen fumarate tablets, dexamethasone sodium phosphate, calcium gluconate injection, methylprednisolone injection, vitamins C and B12, hydrocortisone butyrate cream, Reed acne cream, potassium chloride tablets, and pantoprazole enteric-coated capsules. OUTCOMES: The rash improved after 15 days. LESSONS SUBSECTIONS: There has been little basic research on AGEP-related genetics, and the CARD14 mutation may underlie several pustular rashes, including AGEP and generalized pustular psoriasis. Follow-up studies and further accumulation of patient data are required.