Systemic involvement of acute generalized exanthematous pustulosis: a retrospective study on 58 patients

Acute generalized exanthematous pustulosis: European expert consensus for diagnosis and management

Acute generalized exanthematous pustulosis (AGEP) is a rare, usually drug-induced, acute pustular rash. Despite the lack of strong data supporting the effectiveness of topical or systemic corticosteroids in this drug reaction, they are widely used. More generally, there is no consensus on the diagnostic modalities and the management of patients with AGEP. We aimed to provide European expert recommendations for the diagnosis and management or patients with AGEP. Members of the ToxiTEN group of the European Reference Network (ERN)-skin, all dermatologists and/or allergologists with expertise in drug reactions, elaborated these recommendations based on their own experience and on a review of the literature. Recommendations were separated into the following categories: professionals involved, assessment of the diagnosis of AGEP, management of the patient and allergological work-up after the acute phase. Consensus was obtained among experts for the list of professionals involved for the diagnosis and management of AGEP, including the minimum diagnostic work-up, the setting of management, the treatments, the modalities and the timing of allergological work-up and follow-up. European experts in drug allergies propose herein consensus on the diagnosis and management of patients with AGEP. A multidisciplinary approach is warranted, including dermatologists, allergologists and pharmacovigilance services.

Drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms. Part II diagnosis and management

Drug-induced hypersensitivity syndrome, also known as drug reaction with eosinophilia and systemic symptoms, is a severe cutaneous adverse reaction characterized by an exanthem, fever, and hematologic and visceral organ involvement. The differential diagnosis includes other cutaneous adverse reactions, infections, inflammatory and autoimmune diseases, and neoplastic disorders. Three sets of diagnostic criteria have been proposed; however, consensus is lacking. The cornerstone of management is immediate discontinuation of the suspected drug culprit. Systemic corticosteroids remain first-line therapy, but the literature on steroid-sparing agents is expanding. Longitudinal evaluation for sequelae is recommended. Adjunctive tests for risk stratification and drug culprit identification remain under investigation. Part II of this continuing medical education activity begins by exploring the differential diagnosis and diagnosis of drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms and concludes with an evidence-based overview of evaluation and treatment.

Management of Pustular Psoriasis; The Way Ahead

Pustular psoriasis is a specialized variant of psoriasis which can be life threatening if not treated at the earliest. The pathogenesis has been recently linked to the role of interleukin 36. Apart from the corticosteroids, systemic antipsoriatics like acitretin, cyclosporine and methotrexate have been used with some success though unpredictable. With recent identification of role of IL-36 in the pathogenesis of pustular psoriasis, biologics targeting the IL-36 receptors have been used to manage the situation with high degree of success. This narrative review deals with the recent concepts of pathogenesis of pustular psoriasis as well as the current management scenario.

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 associated with clindamycin in a patient with Hailey-Hailey disease

A 61-year-old African-American female with moderately controlled Hailey-Hailey disease (HHD) presents to the emergency department with a rash and fever. One day prior to her presentation, she was started on oral clindamycin for a tooth extraction procedure. Her physical examination shows diffuse erythema on the trunk and extremities with multiple nonfollicular pustules. A punch biopsy of her upper extremity revealed intraepidermal acantholysis, neutrophilic spongiosis, and subcorneal pustules. The perivascular and interstitial superficial dermal infiltrate is mixed and composed of predominantly neutrophils, with lymphocytes and rare eosinophils. These findings suggest a superimposed acute generalized exanthematous pustulosis (AGEP) in the background of HHD. AGEP is a potentially severe cutaneous condition characterized by the abrupt onset of numerous nonfollicular pustules in a background of pruritic edematous erythroderma. To date, only two case reports have described AGEP in patients with HHD. Early diagnosis of AGEP is essential to initiate prompt and aggressive systemic therapy, prompt medication cessation, close monitoring for end-organ damage, and improve overall morbidity and mortality.

Acute Generalized Exanthematous Pustulosis: Clinical Features, Differential Diagnosis, and Management

Acute generalized exanthematous pustulosis (AGEP) is a rare, acute, severe cutaneous adverse reaction mainly attributed to drugs, although other triggers, including infections, vaccinations, ingestion of various substances, and spider bites, have also been described. AGEP is characterized by the development of edema and erythema followed by the eruption of multiple punctate, non-follicular, sterile pustules and subsequent desquamation. AGEP typically has a rapid onset and prompt resolution within a few weeks. The differential diagnoses for AGEP are broad and include infectious, inflammatory, and drug-induced etiologies. Diagnosis of AGEP depends on both clinical and histologic criteria, as cases of overlap with other disease processes have been reported. Management includes removal of the offending drug or treatment of the underlying cause, if necessary, and supportive care, as AGEP is a self-limited disease. This review aims to provide an overview and update on the epidemiology, pathogenesis, reported precipitating factors, differentials, diagnosis, and management of AGEP.

COVID-19 infection leading to acute pustular dermatoses

Viral infections, including SARS-CoV-2, the virus that causes COVID-19 infection, have been implicated in the development of pustular dermatoses, including generalized pustular psoriasis (GPP) and acute generalized exanthematous pustulosis (AGEP). We performed a literature review of existing cases of GPP and AGEP associated with COVID-19 infection and/or treatment reported over a period of 12 months. We summarize the clinical characteristics of these cases and report an additional six new cases of GPP and AGEP. Seven patients with COVID-19 infection were diagnosed with new-onset or exacerbated GPP, and 33 patients were diagnosed with AGEP. In 55% of the cases, no concomitant potential culprit drug trigger was identified. We present this review of cases of COVID-associated acute pustular dermatoses to further contribute to the spectrum of cutaneous eruption associated with SARS-CoV-2 infection.

Clinical features of acute generalized exanthematous pustulosis caused by hydroxychloroquine in rheumatology patients and exploration of CARD14 gene mutations

Introduction

Acute generalized exanthematous pustulosis (AGEP) is a rare condition characterized by superficial pustules following drug ingestion or infection. Currently, there is no clear link between rheumatism and AGEP. It has been described that hydroxychloroquine (HCQ) is a rare cause of acute generalized epidermal necrolysis (AGEP). Presently, there are limited studies on HCQ-induced AGEP. We aimed to explore the clinical features and associated gene expression of AGEP induced after HCQ treatment exposure in rheumatology patients.

Methods

We assessed patients with HCQ-induced AGEP diagnosed at the Second Affiliated Hospital of Guizhou University of Chinese Medicine between January 1, 2017, and May 1, 2022. We also reviewed similar cases reported in specific databases.

Results

The study included five females (mean age, 40.2 years), and the mean time from initiation of HCQ treatment to symptom onset was 12.2 d. All patients received steroids and allergy medications after HCQ discontinuation, and the rash completely resolved within an average of 25.2 d. We performed whole exome sequencing and Sanger validation in our patient sample. CARD14 gene mutations were detected in three patients. Additionally, seven mutation sites were detected.

Discussion

HCQ-induced AGEP may have a longer latency period and regression time than AGEP induced by other drugs. Our patients all experienced CARD14 gene mutations. AGEP often resolves with topical therapy and drug discontinuation, although some cases require systemic steroid therapy. In the future, patients with rheumatism should pay attention to the effectiveness of HCQ during treatment and be aware of the associated skin toxicity.

DRESS syndrome: A literature review and treatment algorithm

Drug reaction with eosinophilia and systemic symptoms, known by its acronym in English as DRESS (Drug Reaction with Eosinophilia and Systemic Symptoms), clinically manifests with fever, facial edema, lymphadenopathy, a morbilliform rash, and organ involvement. Laboratory results reveal leukocytosis, atypical lymphocytes, eosinophilia, and alterations of liver and kidney function tests. The actual incidence of DRESS is unknown, because it may vary depending on the type of medication and the immune status of each patient; also, because many cases remain undiagnosed or untreated. The drugs most associated with DRESS include antiepileptics, antibiotics, antituberculosis, and non-steroidal anti-inflammatory agents (NSAIDs). Its diagnosis is sometimes made late and can become a challenge. The diagnostic criteria proposed by the international Registry of Severe Cutaneous Adverse Reactions (RegiSCAR) help to establish the diagnosis through a score system based on clinical and laboratory findings. The first step to identify the culprit is a thorough clinical history that includes all suspects, emphasizing those most known to cause DRESS syndrome according to the context and the literature. A skin biopsy may also be helpful in the diagnostic process. Patch testing is the test of choice to search for the culprit in cases of DRESS. Regarding prognosis, the estimated mortality due to DRESS is 3.8%. The main causes of mortality include fulminant hepatitis and liver necrosis. Several indicators of poor prognosis have been identified and these include an eosinophil count above 6000 × 10³/μL, thrombocytopenia, pancytopenia, leukocytosis and coagulopathy. This article aims to review the evidence available regarding the epidemiology, pathophysiology, clinical and laboratory findings, diagnosis, and treatment of DRESS.

Clinical Manifestations and Management of Terbinafine-Induced Acute Generalized Exanthematous Pustulosis

Background. Acute generalized exanthematous pustulosis (AGEP) is a rare and serious adverse reaction of terbinafine. Understanding AGEP and terbinafine is primarily based on case reports. The purpose is to explore the clinical characteristics of terbinafine-induced AGEP, and to provide reference for clinical diagnosis and treatment. Methods. Case reports and original studies of terbinafine-induced AGEP were retrieved by searching Chinese and English databases from January, 1991, to May 31, 2022. Results. The median age of the 32 patients (17 males and 15 females) was 55 years (range: 6–84). The median time to onset of AGEP is 8 days (range: 1–77) and is usually accompanied by fever (>38°C) and elevated neutrophil levels (>8000/mm3). Four patients (12.5%) had oral mucosal involvement, and 10 patients (31.3%) developed postpustular desquamation. The lesions were mainly distributed in the trunk (43.8%), the whole body (34.4%), and the extremities (53.1%). Skin biopsy revealed subcorneal pustules (65.6%), intraepidermal cavernous pustules (43.8%), necrotic keratinocytes (15.6%), spongy hyperplasia (25.0%), neutrophil exocytosis (34.4%), and papillary dermal edema (40.6%). AGEP resolved completely in all patients at a median time of 12 days (range: 2–90) after discontinuation of terbinafine and symptomatic therapy. Conclusion. Clinicians should be aware that terbinafine-induced AGEP is a rare cutaneous adverse reaction. AGEP usually occurs within 2 weeks after administration and has a good prognosis after discontinuation.

The Man of a Thousand Pustules: A Case About Acute Generalized Exanthematous Pustulosis

Acute generalized exanthematous pustulosis (AGEP) is a rare entity characterized by fever associated with the sudden appearance of erythematous lesions, on which multiple sterile, non-follicular pustules develop. We describe a case of a 44-year-old healthy male who developed fever and multiple erythematous and edematous lesions with progressive generalization to the entire body, associated with multiple small non-follicular pustules three days after having started flucloxacillin for the treatment of a furuncle. Considering the characteristics of the exanthema, fever, and association with aminopenicillin initiation, AGEP was considered. A skin biopsy revealed subcorneal and superficial epidermal pustules, with foci of spongiosis, papillary edema, and a superficial, perivascular inflammatory cell infiltrate with neutrophils and eosinophils, consistent with the clinical diagnosis of AGEP. The culprit drug was suspended, and prednisolone was started, considering the rash extension, with progressive and complete improvement. Although it is a rare condition, the hypothesis of AGEP should be considered in acute febrile conditions with disseminated pustules. It resolves spontaneously after discontinuation of the offending drug, and the diagnosis is based on clinical presentation and skin biopsy.

Annular drug eruptions

Cutaneous adverse drug reactions are undesirable cutaneous changes caused by medications. Drug eruptions can mimic a wide range of dermatoses that include exanthematous (morbilliform), urticarial, pustular, bullous, papulosquamous, or granulomatous lesions, and sometimes these eruptions may present with annular, polycyclic, or polymorphous configurations. The correct identification of a cutaneous drug eruption depends on a high index of suspicion, detailed medication exposure history, chronologic evaluation of the causal relationships between drug exposures and eruptions, and the exclusion of other infectious or idiopathic diseases. Most drug eruptions are annoying but self-limited, usually resolving after the withdrawal of the causative agents. Rarely, patients have severe cutaneous adverse reactions, such as Stevens-Johnson syndrome, toxic epidermal necrolysis, and drug reaction with eosinophilia and systemic symptoms (DRESS), which are potentially lethal adverse drug reactions that involve the skin and mucous membranes and may also damage internal organs. Prompt recognition of the alarming signs of severe cutaneous adverse reactions and providing adequate treatment may thus be life-saving. We present the main clinical presentations, histopathology, possible implicated medications, and treatment of cutaneous adverse drug reactions that can present in annular configurations.

Recognizing Drug Hypersensitivity in Pigmented Skin

The imagery of pigmented skin is underrepresented in teaching materials such as textbooks, journals, and online references, and this has resulted in poorer diagnostic and management outcomes of skin pathology, including delayed cutaneous drug hypersensitivity reactions. In this review, we use clinical images to highlight factors that impact clinical presentations and sequelae of drug hypersensitivity reactions in pigmented skin compared with nonpigmented skin. We describe clinical features in some anatomic sites that aid diagnosis or are associated with more severe sequelae. Finally, we discuss strategies that may aid the diagnosis and management of these reactions in pigmented skin.

Results of patch testing in Acute generalized exanthematous pustulosis (AGEP): a literature review

The literature on positive patch test results in acute generalized exanthematous pustulosis (AGEP) is reviewed. 93 drugs were identified that have together caused 259 positive patch tests in 248 patients suffering from AGEP. The drug classes causing the highest number of reactions are beta-lactam antibiotics (25.9%), other antibiotics (20.8%), iodinated contrast media (7.3%) and corticosteroids (5.4%), together accounting for nearly 60% of all reactions. The highest number of reactions to individual drugs was to amoxicillin (n=36), followed by pristinamycin (n=25), diltiazem (n=14), amoxicillin-clavulanic acid (n=13), clindamycin (n=11) and iomeprol (n=8); 59 of the 93 drugs each caused a single case only. The "Top-10" drugs together caused over 50% of all reactions. The sensitivity of patch testing (percentage of positive reactions) in patients with AGEP is largely unknown, but may generally be around 50%, which also applies to pristinamycin. Patch testing in AGEP appears to be safe, although mild recurrence of AGEP skin symptoms or other rashes may occur occasionally. Clinical aspects of AGEP, including epidemiology, etiology and pathophysiology, clinical features, histology, treatment, and prognosis are briefly presented, as are diagnosing the disease and identifying the culprit drugs with patch tests, intradermal tests, in vitro tests, and challenge tests. This article is protected by copyright. All rights reserved.

Clinical Characteristics, Disease Course, and Outcomes of Patients With Acute Generalized Exanthematous Pustulosis in the US

Importance

Acute generalized exanthematous pustulosis (AGEP) is a rare, severe cutaneous adverse reaction associated with systemic complications. Currently available data are largely limited to small retrospective case series.

Objective

To describe the clinical characteristics, disease course, and outcomes of a heterogeneous group of patients with AGEP across the US.

Design, Setting, and Participants

A retrospective review of a case series of patients was conducted from January 1, 2000, through July 31, 2020. All 340 included cases throughout 10 academic health systems in the US were scored retrospectively using the EuroSCAR scoring system, and patients with a score corresponding to probable or definite AGEP and aged 18 years or older were included.

Main Outcomes and Measures

Patient demographic characteristics, clinical course, suspected causative agent, treatment, and short- and long-term outcomes.

Results

Most of the 340 included patients were women (214 [62.9%]), White (206 [60.6%]), and non-Hispanic (239 [70.3%]); mean (SD) age was 57.8 (17.4) years. A total of 154 of 310 patients (49.7%) had a temperature greater than or equal to 38.0 °C that lasted for a median of 2 (IQR, 1-4) days. Of 309 patients, 263 (85.1%) developed absolute neutrophilia and 161 patients (52.1%) developed either absolute or relative eosinophilia. Suspected causes of AGEP were medications (291 [85.6%]), intravenous contrast agents (7 [2.1%]), infection (3 [0.9%]), or unknown (39 [11.5%]). In 151 cases in which a single medication was identified, 63 (41.7%) were β-lactam antimicrobials, 51 (33.8%) were non-β-lactam antimicrobials, 9 (6.0%) were anticonvulsants, and 5 (3.3%) were calcium channel blockers. The median time from medication initiation to AGEP start date was 3 (IQR, 1-9) days. Twenty-five of 298 patients (8.4%) had an acute elevation of aspartate aminotransferase and alanine aminotransferase levels, with a peak at 6 (IQR, 3-9) days. Twenty-five of 319 patients (7.8%) experienced acute kidney insufficiency, with the median time to peak creatinine level being 4 (IQR, 2-5) days after the AGEP start date. Treatments included topical corticosteroids (277 [81.5%], either alone or in combination), systemic corticosteroids (109 [32.1%]), cyclosporine (10 [2.9%]), or supportive care only (36 [10.6%]). All-cause mortality within 30 days was 3.5% (n = 12), none of which was suspected to be due to AGEP.

Conclusions and Relevance

This retrospective case series evaluation of 340 patients, the largest known study cohort to date, suggests that AGEP onset is acute, is usually triggered by recent exposure to an antimicrobial, may be associated with liver or kidney complications in a minority of patients, and that discontinuation of the triggering treatment may lead to improvement or resolution.

Drug Triggers and Clinic of Acute Generalized Exanthematous Pustulosis (AGEP): A Literature Case Series of 297 Patients

Acute generalized exanthematous pustulosis (AGEP) is a rare skin reaction, commonly caused by drugs. Available evidence mostly relies on small studies or case reports. We collected published AGEP case reports and, subsequently, described the patient characteristics, suspect and concomitant drugs, time to onset, disease management, and clinical prognosis. This study included 297 AGEP patients (64.3% women) obtained from 250 published case reports or case series with individual patient data. AGEP affected patients of all ages, but the majority of patients (88.2%) were ≥25 years old. The most frequently reported suspect drugs were anti-infectives for systemic use (36.5%), particularly antibacterials for systemic use (31.0%), and especially beta-lactam antibacterials (18.3%) and macrolides (4.3%). Other frequent suspect drugs were antineoplastics (12.2%), and anti-inflammatory/anti-rheumatic products (5.2%) plus hydroxychloroquine (12.8%). Mean time to onset was 9.1 days (standard deviation SD 13.94). Some patients developed fever (64.3%) and systemic involvement (18.9%), and most patients (76.4%) received pharmacological treatment for AGEP. Seven patients died, although five of them were already critically ill prior to AGEP. In conclusion, antibiotics remain the most common suspected cause of AGEP. While case mortality rate may be up to 2.5%, disentangling the role of AGEP on the fatal outcome from the role of the preexisting health conditions remains challenging.

Clinical characteristics and management of acute generalized exanthematous pustulosis with haemodynamic instability

Background

Acute generalized exanthematous pustulosis (AGEP) is a severe pustular drug eruption with rare reports of haemodynamic instability.

Objective

To describe the clinical characteristics, management, and outcomes of patients with AGEP‐associated haemodynamic instability.

Methods

This retrospective case series identified adult patients diagnosed with AGEP who had haemodynamic instability from November 2012 to February 2020 that were seen at two academic teaching hospitals with roles as a burn centre and tertiary referral centre at the University of Texas Southwestern Medical Center in Dallas, TX USA. Patients with a discharge diagnosis of AGEP that had haemodynamic instability during their eruption were included. Patients with a history of psoriasis, presentations thought to be a flare of generalized pustular psoriasis, or concurrent infection during eruption were excluded. AGEP with haemodynamic instability was characterized by degree of hypotension, dermatologic phenotype at time of dermatologic consultation, and management approach.

Results

This study included 19 patients with AGEP‐associated haemodynamic instability (mean age, 52 years; age range, 29–76 years; 11 (58%) female). Patients were classified on a spectrum of haemodynamic instability; three had sustained hypotension, 10 had hypotension with organ dysfunction, and six had shock. Patients with AGEP‐associated haemodynamic instability had a range of dermatologic phenotypes at initial consultation: subtle exanthematous eruption with minimal pustules, typical eruption with pustules and flexural predominance, and severe eruption with features of Stevens–Johnson syndrome. Both topical and systemic corticosteroids were used for treatment of several patients. Of the patients that required vasopressors and received systemic steroids, the majority were off vasopressors within 24 h of steroid initiation.

Conclusion

Approximately 22% of patients presenting with AGEP to a tertiary referral center had haemodynamic instability. Clinicians should be aware that dermatologic phenotype of AGEP at presentation does not correlate with development of haemodynamic instability.

Pustular Psoriasis and Acute Generalized Exanthematous Pustulosis

The similarity between pustular psoriasis (PP) and acute generalized exanthematous pustulosis (AGEP) poses problems in the diagnosis and treatment of these two conditions. Significant clinical and histopathologic overlap exists between PP and AGEP. PP is an inflammatory disorder that has numerous clinical subtypes, but all with sterile pustules composed of neutrophils. AGEP is a severe cutaneous adverse reaction that is also characterized by non-follicular sterile pustules. Clinical features that suggest a diagnosis of PP over AGEP include a history of psoriasis and the presence of scaling plaques. Histologically, eosinophilic spongiosis, vacuolar interface dermatitis, and dermal eosinophilia favor a diagnosis of AGEP over PP. Importantly, PP and AGEP vary in clinical course and treatment. PP treatment involves topical steroids, oral retinoids, and systemic immunosuppressants. Newer therapies targeting IL-36, IL-23, IL-1, and PDE-4 have been investigated. The removal of the offending agent is a crucial part of the treatment of AGEP.

A Case of Acute Generalized Exanthematous Pustulosis by Cefixime with Oral Mucosal Involvement

Acute generalized exanthematous pustulosis (AGEP) is a rare severe cutaneous adverse reaction characterized by the development of numerous sterile and non-follicular pustules on an erythematous base with no or minimal mucous membrane involvement associated with fever and leucocytosis. Cefixime is a cephalosporin-type beta-lactam antibiotic commonly used for the management of several infections. The Cefixime-induced AGEP cases are known to be rare. Here, we present the case report of a 26-year old female who developed Cefixime-induced AGEP with mucosal membrane involvement. To the best of our knowledge, this is the first case to report the mucosal membrane involvement in Cefixime-induced AGEP. We are presenting this case report to draw the attention on the existence and plethora of symptoms of Cefixime-induced AGEP hoping that the clinicians will reckon these in their differential diagnosis and implement the appropriate management strategies for this rare adverse event in their clinical practice.

Current Perspectives on Severe Drug Eruption

Adverse drug reactions involving the skin are commonly known as drug eruptions. Severe drug eruption may cause severe cutaneous adverse drug reactions (SCARs), which are considered to be fatal and life-threatening, including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), acute generalized exanthematous pustulosis (AGEP), and drug reaction with eosinophilia and systemic symptoms (DRESS). Although cases are relatively rare, approximately 2% of hospitalized patients are affected by SCARs. There is an incidence of 2 to 7 cases/million per year of SJS/TEN and 1/1000 to 1/10,000 exposures to offending agents result in DRESS. However, the mortality rate of severe drug eruptions can reach up to 50%. SCARs represent a real medical emergency, and early identification and proper management are critical to survival. The common pathogenesis of severe drug eruptions includes genetic linkage with HLA- and non-HLA-genes, drug-specific T cell-mediated cytotoxicity, T cell receptor restriction, and cytotoxicity mechanisms. A multidisciplinary approach is required for acute management. Immediate withdrawal of potentially causative drugs and specific supportive treatment is of great importance. Immunoglobulins, systemic corticosteroids, and cyclosporine A are the most frequently used treatments for SCARs; additionally, new biologics and plasma exchange are reasonable strategies to reduce mortality. Although there are many treatment methods for severe drug eruption, controversies remain regarding the timing and dosage of drug eruption. Types, dosages, and indications of new biological agents, such as tumor necrosis factor antagonists, mepolizumab, and omalizumab, are still under exploration. This review summarizes the clinical characteristics, risk factors, pathogenesis, and treatment strategies of severe drug eruption to guide clinical management.

Drug Allergy and Cutaneous Adverse Reactions

Allergy or hypersensitivity to drugs often affects the skin and sometimes also mucosa. While immediate type reactions show a rather homogeneous pattern, delayed type reactions reveal a high variability. In both cases it may not always be easy to differentiate drug reactions from non-drug-induced skin conditions. Furthermore, the different types of cutaneous adverse reactions may be difficult to distinguish in the beginning. This accounts predominately for delayed hypersensitivity reactions that can occur after a variety of medications and present with manifold lesions. Most of these cutaneous adverse reactions are mild, but some are severe with high morbidity and mortality. In the clinical setting, it is important to recognize the signs that point to a more severe condition early on in order to initiate appropriate management. In addition, it is crucial to identify the potentially culprit medication on the basis of a detailed medication history and by evaluating the relevant exposure times of certain drugs that differ substantially between the various reaction types. After the acute stage of the adverse reaction is managed successfully, further allergologic testing may be undertaken to confirm the offending drug.

Acute Generalized Exanthematous Pustulosis Caused by Erlotinib in a Patient with Lung Cancer

Acute generalized exanthematous pustulosis (AGEP) is a rare drug-related adverse skin reaction caused mainly by antibiotics. Erlotinib is an epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) used to treat lung cancer. A 69-year-old woman with primary lung cancer (adenocarcinoma, cT3N1M1b, stage IVB) developed erythema and multiple skin pustules on her abdomen and both thighs after 7 weeks of erlotinib treatment. She also had fever and general fatigue. Histological examination of a skin biopsy specimen showed intraepidermal pustules with neutrophil and eosinophil infiltration. She was diagnosed with erlotinib-induced AGEP. AGEP resolved by erlotinib discontinuation and systemic corticosteroid treatment. The lung cancer progressed when erlotinib was discontinued, so afatinib, a second-generation EGFR-TKI, was administrated without any skin adverse effects. Afatinib successfully decreased the lung cancer, and maintained the disease stable for 1 year. Although acneiform rash was the most common skin adverse event caused by EGFR, AGEP rarely occurred. The present case also demonstrated that it is possible to switch agents, from erlotinib to afatinib, even though they have the same pharmacological effects. Although AGEP is a rare drug-related skin disorder, physicians should be aware that erlotinib may induce AGEP.

Acute Generalized Exanthematous Pustulosis (AGEP) in 12 Patients Treated for SARS-CoV-2 Positive Pneumonia

ABSTRACT

The novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is rapidly spreading throughout the world. The study describes 12 patients with SARS-CoV-2 pneumonia, who developed an acute erythematous rash with nonfollicular pinhead-sized pustules, without mucosal involvement. The clinical differential diagnosis was viral rash, acute generalized exanthematous pustulosis (AGEP), or multiform erythema. computed tomography with a diagnosis of interstitial pneumonia and a respiratory tract sample positive for SARS-CoV-2 in a reverse transcriptase polymerase chain reaction assay. Patients had signs of respiratory distress and were treated with hydroxychloroquine, darunavir, ritonavir, heparin, ceftriaxone, and azithromycin. Punch biopsies showed subcorneal pustules typical of AGEP. Dermal microvascular injury and thrombosis as described in skin damage by SARS-CoV-2 infection was not observed. The direct immunofluorescence for IgG, IgA, IgM, and C3 was negative in 8 patients investigated. A polymerase chain reaction for RNA SARS-CoV-2 performed on frozen skin was negative in 5 of 6 patients. Most of our patients were treated with systemic corticosteroids. After some days (4-10), the diffuse erythema and pustules had improved. AGEP is classified as a severe cutaneous adverse reaction, provoked by drugs and acute infections. Characteristically, removal of the offending agent leads to spontaneous resolution typically in less than 15 days. The recognition of AGEP is important, in order to avoid confusion with a systemic infection and consequently to avoid incorrect treatment. Cutaneous adverse reactions to drugs are common and are major health problems worldwide causing considerable costs for health care systems. We suggest that in the patients with AGEP during SARS-CoV-2 pneumonia, viral infection is a risk factor for developing drug reaction.

DRESS and AGEP Reactions to Iodinated Contrast Media: A French Case Series

BACKGROUND

Drug reactions with eosinophilia and systemic symptoms (DRESSs) and acute generalized exanthematous pustulosis (AGEP) are potentially severe cutaneous adverse drug reactions.

OBJECTIVE

To describe the clinical findings and sensitization profiles of DRESS and AGEP patients who had been administered iodinated contrast media (ICM).

METHODS

All adult patients in the dermatologist's French Investigators for Skin Adverse Reactions to Drugs (FISARD) network diagnosed with a DRESS or AGEP highly suspected to have been caused by an ICM were included retrospectively.

RESULTS

Thirteen DRESS patients and 19 AGEP patients who had been administered ICM were included, and the median delay in DRESS and AGEP occurrence after ICM administration was short, 4 and 1 days, respectively. Five AGEP patients had systemic involvement. A high cosensitization rate (46%) was observed among the DRESS patients, mainly with beta-lactam antibiotics. Overall, 77% of our patients were sensitized to several ICM. Patch tests identified the suspected ICM for 21 cases (72%). The retrospective nature, the limited number of subjects, the absence of a control group of healthy individuals, and the lack of detailed information on previous exposure to sensitizing drugs are limitations of this study.

CONCLUSIONS

We report a large series of DRESSs and AGEPs related to ICM administration. Skin tests appear useful for diagnosis and potentially to identify alternative ICM.

Acute generalized exanthematous pustulosis: Epidemiology, clinical course, and treatment outcomes of patients treated in an Asian academic medical center

Background

Acute generalized exanthematous pustulosis (AGEP) is a rare severe cutaneous adverse drug reaction. Although acutely patients have significant morbidity and occasional systemic involvement, the clinical course is generally self-limited. To date, there has been no consensus on treatment.

Objective

The aim of our current study was to evaluate the clinical features, drug association, treatment, and outcomes in a cohort of patients treated in an academic medical center.

Methods

A retrospective review of electronic medical records over a period of 10 years from 2009 to 2018 in a single tertiary academic medical center in Singapore was performed. Forty-three medical records with probable/definite diagnosis of AGEP were identified and analyzed for statistical significance.

Results

Drug association was identified in 93% of cases. The most frequent drug class was antibiotics, including penicillins, cephalosporins, and vancomycin. Systemic involvement was reported in 13.9% of patients. All cases of AGEP resolved with cessation of the offending drug. There was no mortality attributed to AGEP. Treatment with systemic steroid was associated with a decreased length of hospital stay (P = .035) in patients with AGEP.

Conclusion

AGEP was a self-limiting adverse drug reaction that was commonly caused by antibiotics. Although there was no difference in mortality, there was a significant reduction in the length of hospitalization with systemic corticosteroid treatment compared with that of topical corticosteroid treatment of AGEP.

Acute Generalized Exanthematous Pustulosis with Multiple Organ Failure

Acute generalized exanthematous pustulosis (AGEP) is a rare, self-limiting condition. It presents with sterile skin pustules. We present a middle-aged lady with fluid nonresponsive circulatory shock and multiple organ dysfunction secondary to AGEP.

A Rare Case of Acute Generalized Exanthematous Pustulosis with Drug-Induced Liver Injury caused by Pyrazinamide

Acute Generalized Exanthemataous Pustulosis (AGEP) is a rare acute pustular eruption that is mostly induced by drugs. Aside from cutaneous eruptions, systemic symptoms such as leukocytosis, neutrophilia, and internal organ involvement such as liver, kidney, respiratory system, and bone marrow, may occur, although uncommon. Liver involvement usually results in a two- or three-fold increase of liver enzymes and rarely exceeds that. Pyrazinamide is the first-line anti-tuberculosis drug that is potentially hepatotoxic, but rarely shows dermatologic manifestations. We report a rare case of AGEP with drug induced liver injury due to pyrazinamide in a young patient with tuberculosis.

Acute generalized exanthematous pustulosis with a focus on hydroxychloroquine: A 10-year experience in a skin hospital

OBJECTIVE

Acute generalized exanthematous pustulosis (AGEP) is a severe skin pustular drug reaction that can lead to life-threatening consequences. In this study, we have investigated the characteristics and outcomes of patients with AGEP in a tertiary skin hospital.

METHODS

From March 2007 to December 2019, medical records of all patients diagnosed with AGEP, were assessed. Demographic data, culprit drug, past medical history, laboratory tests, recurrence, and systemic organ involvement were all documented as well.

RESULTS

Seventy-four patients, including 54 women (73%) and 20 men (27%), with a mean age of 44.3 ± 16.5 years were evaluated. The most common comorbidities among the patients were rheumatoid arthritis and diabetes. In addition, hydroxychloroquine, cephalosporin, and amoxicillin were found as the three most common medications associated with AGEP induction. Among the study group, seventeen (23%) patients had systemic organ involvement (nine (12.2%), six (8.1%), and five (6.8%) had hepatic, renal and pulmonary involvement, respectively). All patients responded to oral prednisolone within a median of five days (IQR = 4; ranged 2-14). The median duration of treatment was significantly longer in hydroxychloroquine group compared to other drugs (8 versus 5 days; HR 0.57,95%CI 0·35-0.91). Likewise, the median duration of treatment was significantly longer in febrile patients compared to the afebrile ones (7 versus 4 days; HR 0.46, 95%CI 0.25-0.85). Recurrence occurred in six patients after resuming treatment with the same medication. The mean Naranjo score was 7.6 ± 0.9 denoting a probable causal relationship.

CONCLUSION

In this study, we found that using hydroxychloroquine and presence of fever are the risk factors potentially leading to a prolonged treatment duration of AGEP.

Clinical Presentation and Management of Atypical and Recalcitrant Acute Generalized Exanthematous Pustulosis (AGEP)

Acute generalized exanthematous pustulosis (AGEP) is a severe cutaneous adverse reaction (SCAR) characterized by sterile non-follicular pustules on an erythematous base that form rapidly after drug exposure. AGEP is mediated by numerous cytokines produced by drug specific T-cells that mediate neutrophilic intracorneal, subcorneal, and/or intraepidermal pustule development. Though genetic susceptibility is not fully understood, individuals with mutations in IL-36RN may be at increased risk of AGEP development. AGEP commonly presents with leukocytosis and fever in the acute pustular phase and follows a self-limited desquamative recovery phase upon removal of offending drug. Severe cases of AGEP may have multisystem organ involvement. Atypical presentations of AGEP include localized eruptions and cases with overlapping clinical and histopathological features associated with Stevens-Johnson syndrome/toxic epidermal necrolysis, drug reaction with eosinophilia and systemic symptoms, and generalized pustular psoriasis. Most cases of AGEP clear rapidly with systemic corticosteroids, but severe or recalcitrant cases may require other systemic therapies such as cyclosporine, and intravenous immunoglobulin.

Antibiotic-Impregnated Intramedullary Cement Nail-Induced Acute Generalized Exanthematous Pustulosis and Septic Shock: A Case Report

CASE

A 28-year-old woman with an infected proximal femur nonunion was treated with an antibiotic-coated intramedullary nail. Shortly after discharge, the patient presented to the emergency department and was readmitted with a morbilliform rash sparing the left lower extremity. She became hemodynamically unstable, despite cessation of intravenous antibiotics, requiring transfer to the intensive care unit and urgent removal of her antibiotic nail. She improved after surgery, and biopsy results from the rash confirmed acute generalized examthematous pustulosis.

CONCLUSION

Acute generalized exanthematous pustulosis is a rare, dermatologic crisis that can be precipitated by antibiotics, even in the form of antibiotic cement.

Neutrophilic drug reactions

Neutrophilic drug reactions are unique eruptions that can affect hospitalized patients and share a common pathophysiology with neutrophils as the key mediators of inflammation. They range in clinical presentation from papules and plaques to bullae and erosions to pustules. Although there is some overlap in presentation, each has distinguishing features that aid the clinician in differentiation from one another and from other drug hypersensitivity reactions. Much of the data on these reactions are from case reports and series or retrospective review studies. There are limited prospective observational studies dedicated to these adverse drug reactions. We review the more common and life-threatening neutrophilic drug reactions, their proposed mechanism of action, and their management.

Clindamycin-induced acute generalized exanthematous pustulosis: A case report

RATIONALE

Acute generalized exanthematous pustulosis (AGEP) is a severe pustular cutaneous adverse drug reaction. Sterile, non-follicular pustules overlying the erythematous skin characterize this reaction.

PATIENT CONCERNS

A 30-year-old Asian women presented with sterile, non-follicular lesions with pus-fluid levels on her back 2 days after taking clindamycin. Skin biopsy revealed a spongiotic change in the epidermis with a focal subcorneal pustule and perivascular eosinophil and lymphocyte infiltration.

DIAGNOSIS

Clindamycin-induced AGEP.

INTERVENTIONS

We discontinued clindamycin treatment and prescribed systemic corticosteroids.

OUTCOMES

The pustule stopped spreading within 1 day and the rash improved within 2 days.

LESSONS

AGEP is a pustular cutaneous adverse drug reaction that can appear with pus-fluid levels, clinically mimicking Sneddon-Wilkinson disease. The differentiation between both conditions is a history of drug use, characteristic skin lesions and histopathology.

HLA-B*58: 01 association in allopurinol-induced severe cutaneous adverse reactions: the implication of ethnicity and clinical phenotypes in multiethnic Malaysia

OBJECTIVE

The association between human leukocyte antigen (HLA)-B*58:01 and risk of allopurinol-induced severe cutaneous adverse reactions (AIS) was observed across different populations. We explore the association between HLA-B*58:01 and AIS risk in multiethnic Malaysian population. The HLA-B*58:01 risk for different AIS clinical phenotypes and ethnicity was determined.

METHODS

We performed a case-control association study by genotyping the HLA-B alleles of 55 patients with AIS [11 toxic epidermal necrolysis (TEN), 21 Steven Johnson syndrome (SJS) 22 drug reaction wit eosinophilia and systemic symptoms (DRESS) and one acute generalized exanthematous pustulosis (AGEP)] and 42 allopurinol-tolerant controls (ATC).

RESULTS

HLA-B*58:01 was positive in 89.1 and 14.3% of the AIS and ATC study groups [odds ratio (OR) = 49.0, 95% confidence interval (CI) = 14.6-164.4, P < 0.0001)], respectively. Our data showed that 93.8% of the AIS-SJS/TEN patients and 86.4% of the AIS-DRESS patients were HLA-B*58:01 positive (AIS-SJS/TEN, OR = 90, 95% CI = 16.9-470.1, P < 0.0001 and AIS-DRESS OR = 38, 95% CI = 8.5-169.2, P < 0.0001). Stratification by ethnicity and clinical phenotypes revealed a significant increased risk between HLA-B*58:01 and Chinese-AIS patients (OR = 137.5, 95% CI = 11.3-1680.2, P < 0.0001), in particular Chinese patients with AIS-SJS/TEN phenotype (100% HLA-B*58:01 positive). HLA-B*58:01 was positive in 90.9% Chinese AIS-DRESS (P < 0.0001). Highly significant associations of HLA-B*58:01 were observed in Malay AIS-SJS/TEN (OR = 78, 95% CI = 9.8-619.9, P < 0.0001) and Malay AIS-DRESS (OR = 54, 95% CI = 6.6-442.9, P < 0.0001). Although the number of Indian-AIS patients was relatively small (n = 2), both were HLA-B*58:01 positive.

CONCLUSION

Our data suggest strong associations between HLA-B*58:01 and AIS in Malaysian population with Chinese and Malays ethnicity. The strong association was also observed in three different clinical phenotypes of AIS, mainly the AIS-SJS/TEN.

Clinical Phenotypes of Severe Cutaneous Drug Hypersensitivity Reactions

Drug hypersensitivity reactions are clinically heterogenous ranging from mild to severe. Most drug hypersensitivity reactions are accompanied by cutaneous manifestations. Fever, mucous membrane involvement, large blisters, facial oedema, pustulosis and visceral involvement are clinical features that lead to suspicion of severe adverse drug reactions. Severe cutaneous adverse drug reactions (SCARs) include Stevens-Johnson syndrome, toxic epidermal necrolysis, drug rash eosinophilia and systemic symptoms, acute generalized exanthematous pustulosis. Serum sickness like reactions, drug induced vasculitis and generalized bullous fixed drug eruptions are less severe clinical entities. SCARs are uncommon but associated with significant morbidity and mortality. Physician should be aware of specific red flags and danger signs to immediately identify these reactions. Immediate drug withdrawal is mandatory. Early diagnosis and appropriate treatment significantly affect the prognosis of the disease. The purpose of our review is to discuss clinical phenotypes of severe cutaneous drug hypersensitivity reactions.

Severe Cutaneous Adverse Reactions: A Single-Center Retrospective Study of 173 Patients in China

Background

Severe cutaneous adverse reactions (SCAR) to drugs are a crucial public health issue and the use of systemic corticosteroids in SCAR has been controversial.

Objective

To analyze clinical features, causative drugs, treatment, outcomes, and prognostic factors of SCAR in the case-series of 173 patients, and add more information to the debate of using systemic corticosteroids in SCAR management.

Methods

A retrospective study of 173 SCAR patients diagnosed with drug reaction with eosinophilia and systemic symptoms (DRESS), Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) or acute generalized exanthematous pustulosis (AGEP) at a tertiary care institution in China between January 2014 and December 2017 was conducted.

Results

Of 173 patients, allopurinol, carbamazepine, and antibiotics are the most frequently implicated drugs for DRESS (40.4%), SJS/TEN (26.0%), and AGEP (40.0%) respectively. Moreover, there is a strongly negative correlation between early corticosteroids use and the progression (p=0.000) and severity (p=0.01) of skin lesions. However, there is no association between early corticosteroids use and the mortality of SCAR (odds ratio: 1.01, 95% confidence interval: 0.95~1.08). In addition, lymphadenopathy, eosinophilia, and interval from onset to corticosteroids treatment were correlated with SCAR prognosis.

Conclusion

Prompt short-course systemic corticosteroids use is associated with early-stage skin lesions remission without influencing the disease mortality. Lymphadenopathy and eosinophilia were the independent poor prognostic factors of SCAR.

Human leukocyte antigen-associated severe cutaneous adverse drug reactions: from bedside to bench and beyond

Despite their being uncommon, severe cutaneous adverse drug reactions (SCARs) result in a very great burden of disease. These reactions not only carry with them a high mortality (10%-50%) and high morbidity (60%) with severe ocular complications, alopecia, oral and dental complications and development of autoimmune diseases, but also create a substantial economic burden for patients' families and society. SCARs are, therefore, an important medical problem needing a solution in many countries, especially in Asia. The clinical spectrum of SCARs comprises Stevens-Johnson syndrome, toxic epidermal necrolysis, DRESS (drug rash with eosinophilia and systemic symptoms) (also known as drug hypersensitivity syndrome or drug-induced hypersensitivity syndrome) and acute generalised exanthematous pustulosis. Recent crucial advances in determining genetic susceptibility and understanding how T cells recognise certain medications or their metabolites via the major histocompatibility complex and the effects of cofactors, have led to the implementation of cost-effective screening programs enabling prevention in a number of countries, and to further understanding of the patho-mechanisms involved in SCARs and their significance. In this review, we document comprehensively the journey of SCARs from bedside to bench and outline future perspectives in SCARs research.