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.

Genotyping HLA alleles to predict the development of Severe cutaneous adverse drug reactions (SCARs): state-of-the-art.

Introduction: Pharmacogenomics has great potential in reducing drug-induced severe cutaneous adverse drug reactions (SCARs). Pharmacogenomic studies have revealed an association between HLA genes and SCARs including acute generalized exanthematous pustulosis (AGEP), drug reaction with eosinophilia and systemic symptoms (DRESS), Stevens-Johnson syndrome (SJS), and toxic epidermal necrolysis (TEN).Areas covered: Pharmacogenomics-guided therapy could prevent severe drug hypersensitivity reactions. The US Food and Drug Administration (FDA), Clinical Pharmacogenetics Implementation Consortium (CPIC), and Dutch Pharmacogenetics Working Group (DPWG) provided guidelines in the translation of clinically relevant and evidence-based SCARs pharmacogenomics research into clinical practice. In this review, we intended to summarize the significant HLA alleles associated with SCARs induced by different drugs in different populations. We also summarize the SCARs associated with genetic and non-genetic factors and the cost-effectiveness of screening tests.Expert opinion: The effectiveness of HLA screening on a wider scale in clinical practice requires significant resources, including state-of-the-art laboratory; multidisciplinary team approach and health care provider education and engagement; clinical decision support alert system via electronic medical record (EMR); laboratory standards and quality assurance; evidence of cost-effectiveness; and cost of pharmacogenomics tests and reimbursement.

Acute generalized exanthematous pustulosis and Stevens-Johnson syndrome overlap due to hydroxychloroquine: a case report.

BACKGROUND: Since the World Health Organization declared a global pandemic due to the novel coronavirus disease2019, there have been targeted efforts to establish management modalities. Hydroxychloroquine has been suggested as a possible treatment; however, it is associated with multiple adverse reactions. We report a rare case of a patient with acute generalized exanthematous pustulosis with Stevens-Johnson syndrome due to hydroxychloroquine. Acute generalized exanthematous pustulosis is characterized by acute onset of a generalized rash that is pustular and erosive in nature, affecting limbs; trunk; face; and, less often, mucosal membranes. Although rare, it is important to be mindful of this side effect because the diagnosis is often delayed, and the disease has the potential to be life-threatening. CASE PRESENTATION: A 68-year-old American woman presented to our hospital with a painful, rapidly spreading rash. Its morphologic features included erythema multiforme-like lesions with extensive skin sloughing in various regions of the head, neck, and trunk and mucosal involvement. Her Nikolsky sign was negative, and she had no evidence of lesions on areas of skin trauma. Four weeks prior, she had been initiated on hydroxychloroquine for a presumed diagnosis of cutaneous sarcoidosis. Three punch biopsies of the head and neck area revealed subcorneal pustules consistent with acute generalized exanthematous pustulosis. Treatment began with high doses of methylprednisolone, leading to only minimal improvement of existing areas and ongoing spread to new areas. Treatment with intravenous immunoglobulin was initiated, at which point disease stability was achieved. The patient's rash ultimately resolved, as did her cutaneous pain and pruritus. CONCLUSIONS: Among many potential adverse reactions involving hydroxychloroquine, cutaneous side effects are varied and can lead to significant morbidity or even death. The drug is currently being investigated in a multitude of trials for coronavirus disease2019 treatment, prevention, and prophylaxis after exposure to severe acute respiratory syndrome coronavirus 2. Acute generalized exanthematous pustulosis is a rare side effect of hydroxychloroquine, and even fewer cases demonstrate histologic evidence of acute generalized exanthematous pustulosis while clinically presenting with Stevens-Johnson syndrome. Patients who develop Stevens-Johnson syndrome/toxic epidermal necrolysis require best supportive care with aggressive fluid and electrolyte replacement and prevention of further breakdown of the skin barrier. With the potential of widespread hydroxychloroquine use, it is important that providers be aware of its potential severe adverse drug reactions.

Acute generalized exanthematous pustulosis due to ceftriaxone: Report of a pediatric case with recurrence after positive patch test.

Acute generalized exanthematous pustulosis (AGEP) is seen uncommonly in children and sometimes shows atypical clinical features in this population. Patch testing can be used effectively in children for the confirmation of the culprit drug in cases of multiple drug use. Here, we report a rare, pediatric case of ceftriaxone-induced AGEP confirmed by patch testing with subsequent recurrence of the skin eruption.

Acute generalized exanthematous pustulosis: an overview of the clinical, immunological and diagnostic concepts.

Acute generalized exanthematous pustulosis (AGEP) is a significant adverse cutaneous reaction, most often provoked by drugs and acute infections. The recognition of AGEP is important, in order to avoid confusion with a systemic infection and consequently to avoid incorrect treatment. The clinical hallmark is the presence of multiple disseminated sterile pustules on an erythematous background, associated with fever and a massive neutrophilia and sometimes eosinophilia. The disease is characterised by an acute onset and a spontaneous resolution within 2 weeks. The involvement of drug-specific T cells in the pathomechanism can be confirmed by positive skin patch tests and lymphocyte transformation tests. In this review, we highlight the main clinical, pathophysiological and diagnostic aspects of this peculiar form of drug allergy.

A comparison of Ki-67 antigen presentation in acute generalized exanthematous pustulosis and pustular psoriasis.

Ki-67 is an established marker of cell proliferation. It is highly expressed in psoriasis and correlated with the clinical severity of psoriasis. Higher number of Ki-67 positive keratinocytes has been observed in pustular psoriasis (PP) as compared with psoriasis vulgaris. As for Acute generalized exanthematous pustulosis (AGEP), a distinct disease entity but similar in many aspects of clinicopathologic features to PP, Ki-67 immunostaining presentation has never been investigated before. This study aimed to compare Ki-67 immunostaining presentation between PP and AGEP. By immunohistochemical staining, we compared Ki-67 immunostaining presentation on skin lesions of five patients of AGEP and five age-matched patients of PP. Ki-67 positive keratinocytes were counted and mean values were determined to compare between PP and AGEP. An augmented presence of Ki-67 positive keratinocytes was found in both AGEP and PP and they distributed not only in basal cell layer but in middle or even upper part of epidermis. Statistical analysis using Mann-Whitney U test showed no difference of epidermal proliferation rate between the two groups (P = 0.222). The results showed there was no difference of Ki-67 immunostaining presentation between AGEP and PP. Besides, we found marked increase of Ki-67-positive proliferating keratinocytes in AGEP and suggested that epidermal hyperproliferation may also play an important role in the formation of AGEP. We also discussed the possible pathophysiology of AGEP, possible epidermal architecture changes in AGEP and PP, and found the similarity in pathophysiology of AGEP and PP.

Pustulosis exantemática aguda generalizada asociada a Epstein Barr: A propósito de un caso / Acute generalized exanthematous pustulosis associated to Epstein Barr: A propose of a case

Acute generalized exanthematous pustulosis (AGEP) is a rare skin eruption most commonly caused by medications. It is characterized by an acute eruption of sterile pustules and it is accompanied by an episode of fever, which regresses a few days after discontinuation of the drug that caused the condition. We report a case 23 year-old woman without history of psoriasis, that consults for fever and an acute generalized pustular eruption after amoxicillin, with clavulanic acid administration in a mononucleosis infection context, which resolved spontaneously. The microbiologic culture was negative for pathogenic germens.

La pustulosis exantemática aguda generalizada (PEAG) es una rara afección de hipersensibilidad, inducida principalmente por drogas y se manifiesta por una erupción aguda de pústulas estériles, acompañada de fiebre, que regresa en pocos días luego de discontinuar el fármaco causante. Se comunica el caso de una paciente de 23 años de edad, sin antecedentes de psoriasis que consulta por fiebre y una erupción pustulosa generalizada, asociada a la ingesta previa de amoxicilina y ácido clavulánico en el contexto de una mononucleosis infecciosa, con resolución espontánea del cuadro. El cultivo microbiológico no objetivó gérmenes patógenos.