Several herpesviruses can reactivate in a severe drug-induced multiorgan reaction in the same sequential order as in graft-versus-host disease

Drug Allergy Mimics

When approaching a case of apparent drug allergy, the consulting clinician should consider a broad differential diagnosis. This article presents a series of cases that could be commonly referred to an allergist for assessment as "drug allergy," however, a real diagnosis exists that mandates a different diagnostic and treatment strategy, including a case of inducible laryngeal obstruction, multiple drug intolerance syndrome, viral rash, seizure due to metastatic malignancy, and hemophagocytic lymphohistiocytosis initially diagnosed as drug reaction and eosinophilia with systemic symptoms. The initial misdiagnoses of these patients delayed or interfered with their medical care, emphasizing the importance of accurate diagnoses for the benefit of our patients.

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.

Clinical observation and analysis of rash caused by lacosamide in children with epilepsy

PURPOSE

To draw clinical attention to rashes caused by lacosamide.

METHODS

This retrospective analysis included patients admitted to the Department of Pediatrics, Second Affiliated Hospital of Xi'an Jiaotong University between January 2021 and September 2023. We focused on patients who developed rashes after lacosamide treatment and analyzed all patients who exhibited rashes after lacosamide treatment to analyze the risk factors.

RESULTS

In total, 190 patients received lacosamide, of whom four developed allergies (2.1 %). Three patients had severe rashes, and two patients had high fever. All of these adverse events improved after the withdrawal of lacosamide. Of the 13 patients reported to date, including the four patients in this study, eight used various antiseizure medicines, including seven patients who used four or more antiseizure medicines. Four patients underwent testing for HLA-B*1502, and two patients were positive. Patients developed rashes within 1-10 days after treatment initiation, and the duration of the rash ranged 2-37 days.

CONCLUSIONS

Lacosamide-induced rash was detected in 2.1 % of patients in our cohort. Rashes are potentially serious, and prompt evaluation is required. Rashes are more likely to occur when multiple antiseizure medicines are used simultaneously, typically within 10 days of treatment initiation.

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.

Novel insights into molecular and cellular aspects of delayed drug hypersensitivity reactions

INTRODUCTION

Delayed drug hypersensitivity reactions (DDHRs) represent a major health problem. They are unpredictable and can cause life-long disability or even death. The pathophysiology of DDHRs is complicated, multifactorial, and not well understood mainly due to the lack of validated animal models or in vitro systems. The role of the immune system is well demonstrated but its exact pathophysiology still a matter of debate.

AREA COVERED

This review summarizes the current understanding of DDHRs pathophysiology and abridges the available new evidence supporting each hypothesis. A comprehensive literature search for relevant publications was performed using PubMed, Google Scholar, and Medline databases with no date restrictions and focusing on the most recent 10 years.

EXPERT OPINION

Although multiple milestones have been achieved in our understanding of DDHRs pathophysiology as a result of the development of useful experimental models, many questions are yet to be fully answered. A deeper understanding of the mechanistic basis of DDHRs would not only facilitate the development of robust and reliable diagnostic assays for diagnosis, but would also inform therapy by providing specific target(s) for immunomodulation and potentially permit pre-therapeutic risk assessment to pursue the common goal of safe and effective drug therapy.

Advances in understanding of the pathogenesis and therapeutic implications of drug reaction with eosinophilia and systemic symptoms: an updated review

Drug reaction with eosinophilia and systemic symptoms or drug-induced hypersensitivity syndrome (DRESS/DIHS) is one type of severe cutaneous adverse reaction (SCAR). It is featured by fever, widespread skin lesions, protracted clinical course, internal organ involvement, and possibly long-term autoimmune sequelae. The presence of high-risk human leukocyte antigen (HLA) alleles, hypersensitivity reaction after culprit drug ingestion, and human herpesvirus reactivation may all contribute to its complex clinical manifestations. Some recent studies focusing on the roles of involved cytokines/chemokines and T cells co-signaling pathways in DRESS/DIHS were conducted. In addition, some predictors of disease severity and prognosis were also reported. In this review, we provided an update on the current understanding of the pathogenesis, potential biomarkers, and the relevant therapeutic rationales of DRESS/DIHS.

Atypical drug-induced hypersensitivity syndrome with multiple organ failure rescued by combined acute blood purification therapy: a case report

BACKGROUND

Drug-induced hypersensitivity syndrome (DIHS), including Stevens-Johnson syndrome (SJS), is a severe rash that often develops 2-6 weeks after the intake of the causative drug; however, its diagnosis is sometimes difficult. This article describes a case in which a patient with DIHS-induced multiple organ failure was successfully treated with blood purification therapy.

CASE PRESENTATION

A male patient in his 60s was admitted to our hospital with autoimmune encephalitis. The patient was treated with steroid pulse therapy, acyclovir, levetiracetam, and phenytoin. From the 25th day, he presented with fever (≥ 38 °C) as well as miliary-sized erythema on the extremities and trunk, followed by erosions. DIHS and SJS were suspected; accordingly, levetiracetam, phenytoin, and acyclovir were discontinued. On the 30th day, his condition further deteriorated, and he was admitted to the intensive care unit for ventilatory management. The next day, he developed multi-organ failure and was started on hemodiafiltration (HDF) for acute kidney injury. Although he presented with hepatic dysfunction and the appearance of atypical lymphocytes, he did not meet the diagnostic criteria for DIHS or SJS/toxic epidermal necrolysis. Therefore, he was diagnosed with multi-organ failure caused by severe drug eruption and underwent a 3-day treatment with plasma exchange (PE) in addition to HDF. Accordingly, the patient was diagnosed with atypical DIHS. After being started on blood purification therapy, the skin rash began to disappear; moreover, the organ damage improved, with a gradual increase in urine output. Eventually, the patient was weaned off the ventilator and transferred to the hospital on the 101st day.

CONCLUSIONS

HDF + PE could effectively treat multi-organ failure caused by atypical DIHS, which is difficult to diagnose.

Anti-MDA-5 Antibody-positive Dermatomyositis after Allogeneic Bone Marrow Transplantation for Acute Transformation of Chronic Myelogenous Leukemia

Anti-melanoma differentiation-associated gene 5 (MDA-5) antibody-positive dermatomyositis is a disease with a poor prognosis associated with rapid progressive interstitial pneumonia. Autoimmune diseases have occasionally been reported to occur after hematopoietic stem cell transplantation (HSCT). We experienced a case of anti-MDA-5 antibody-positive dermatomyositis after HSCT. In this case, a sufficient dose of cyclophosphamide could not be administered due to an impaired bone marrow function. We discuss the complications of autoimmune diseases after HSCT.

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.

Fever, Rash, and Cough in a 7-Year-Old Boy

A 7-year-old boy presented to the emergency department with fever, cough, congestion, abdominal pain, myalgias, and morbilliform rash. Several aspects of the patient's history, including recent travel, living on a farm, exposure to sick contacts, and new medications, resulted in a wide differential diagnosis. Initial laboratory testing revealed leukocytosis with neutrophilia and elevated atypical lymphocytes, but did not reveal any infectious causes of illness. He was discharged from the hospital, but then represented to the emergency department a day later with worsening rash, continued fever, abdominal pain, and poor intake. He was then admitted. A more comprehensive laboratory evaluation was initiated. During this hospital course, the patient's physical examination changed when he developed head and neck edema, and certain laboratory trends became clearer. With the assistance of several specialists, the team was able to reach a more definitive diagnosis and initiate treatment to appropriately manage his condition.

Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS): Focus on the Pathophysiological and Diagnostic Role of Viruses

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a heterogeneous, multiorgan and potentially life-threatening drug-hypersensitivity reaction (DHR) that occurs several days or weeks after drug initiation or discontinuation. DHRs constitute an emerging issue for public health, due to population aging, growing multi-organ morbidity, and subsequent enhanced drug prescriptions. DRESS has more consistently been associated with anticonvulsants, allopurinol and antibiotics, such as sulphonamides and vancomycin, although new drugs are increasingly reported as culprit agents. Reactivation of latent infectious agents such as viruses (especially Herpesviridae) plays a key role in prompting and sustaining aberrant T-cell and eosinophil responses to drugs and pathogens, ultimately causing organ damage. However, the boundaries of the impact of viral agents in the pathophysiology of DRESS are still ill-defined. Along with growing awareness of the multifaceted aspects of immune perturbation caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the ongoing SARS-CoV-2-related disease (COVID-19) pandemic, novel interest has been sparked towards DRESS and the potential interactions among antiviral and anti-drug inflammatory responses. In this review, we summarised the most recent evidence on pathophysiological mechanisms, diagnostic approaches, and clinical management of DRESS with the aim of increasing awareness on this syndrome and possibly suggesting clues for future research in this field.

Viral infections and drug hypersensitivity

Virus infections and T-cell-mediated drug hypersensitivity reactions (DHR) can influence each other. In most instances, systemic virus infections appear first. They may prime the reactivity to drugs in two ways: First, by virus-induced second signals: certain drugs like β-lactam antibiotics are haptens and covalently bind to various soluble and tissue proteins, thereby forming novel antigens. Under homeostatic conditions, these neo-antigens do not induce an immune reaction, probably because co-stimulation is missing. During a virus infection, the hapten-modified peptides are presented in an immune-stimulatory environment with co-stimulation. A drug-specific immune reaction may develop and manifest as exanthema. Second, by increased pharmacological interactions with immune receptors (p-i): drugs tend to bind to proteins and may even bind to immune receptors. Without viral infections, this low affine binding may be insufficient to elicit T-cell activation. During a viral infection, immune receptors are more abundantly expressed and allow more interactions to occur. This increases the overall avidity of p-i reactions and may even be sufficient for T-cell activation and symptoms. There is a situation where the virus-DHR sequence of events is inversed: in drug reaction with eosinophilia and systemic symptoms (DRESS), a severe DHR can precede reactivation and viremia of various herpes viruses. One could explain this phenomenon by the massive p-i mediated immune stimulation during acute DRESS, which coincidentally activates many herpes virus-specific T cells. Through p-i stimulation, they develop a cytotoxic activity by killing herpes peptide-expressing cells and releasing herpes viruses. These concepts could explain the often transient nature of DHR occurring during viral infections and the often asymptomatic herpes-virus viraemia after DRESS.

Re-Enlightenment of Fulminant Type 1 Diabetes under the COVID-19 Pandemic

Fulminant type 1 diabetes (FT1D) is a subtype of type 1 diabetes (T1D) that is characterized by the rapid progression to diabetic ketoacidosis against the background of rapid and almost complete pancreatic islet destruction. The HbA1c level at FT1D onset remains normal or slightly elevated despite marked hyperglycemia, reflecting the rapid clinical course of the disease, and is an important marker for diagnosis. FT1D often appears following flu-like symptoms, and there are many reports of its onset being linked to viral infections. In addition, disease-susceptibility genes have been identified in FT1D, suggesting the involvement of host factors in disease development. In most cases, islet-related autoantibodies are not detected, and histology of pancreatic tissue reveals macrophage and T cell infiltration of the islets in the early stages of FT1D, suggesting that islet destruction occurs via an immune response different from that occurring in autoimmune type 1 diabetes. From 2019, coronavirus disease 2019 (COVID-19) caused by the novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) spread worldwide and became a serious problem. Reports on the association between SARS-CoV-2 and T1D are mixed, with some suggesting an increase in T1D incidence due to the COVID-19 pandemic. When discussing the association between COVID-19 and T1D, it is also necessary to focus on FT1D. However, it is not easy to diagnose this subtype without understanding the concept. Therefore, authors hereby review the concept and the latest findings of FT1D, hoping that the association between COVID-19 and T1D will be adequately evaluated in the future.

Drug-induced hypersensitivity syndrome induced by propylthiouracil: case report and literature review

Background

Drug-induced hypersensitivity syndrome (DIHS) is a rare, potentially life-threatening systemic drug reaction. Antithyroid drugs (ATDs) causing DIHS have seldom been reported before.

Case presentation

We present a case of propylthiouracil (PTU)-induced DIHS, which included fever, skin rash, lymphadenopathy, hepatosplenomegaly, serious liver and kidney dysfunction, peripheral blood eosinophilia, and atypical lymphocytosis. Following supportive therapy, intravenous immunoglobulin (IVIG), and systemic corticosteroid, the patient experienced a resolution of fever and rash combined with progressive normalization of hematological index and organ function. These clinical features, and the skin lesion biopsy confirmed DIHS diagnosis.

Conclusions

To our knowledge, this is the second reported case of PTU-induced DIHS worldwide and the first human leukocyte antigen (HLA) typing of PTU-induced DIHS. Clinicians should cautiously distinguish hyperthyroidism etiology and identify the indication of ATDs. Timely recognition and formal DIHS treatment are required in patients with ATDs.

A case of severe DRESS syndrome treated with therapeutic plasma exchange and intravenous immunoglobulin therapy

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome in children is a rare adverse drug reaction with skin rash, fever, hematologic abnormalities, and multiorgan involvement. The diagnosis is difficult because of its various clinical presentations, nonetheless is extremely important due to the mortality rate. We describe a 14-year-old boy who developed hypersensitivity to either teicoplanin or meropenem therapy. After failing to improve with corticosteroids, he was successfully treated with therapeutic plasma exchange (TPE). TPE should be considered in the treatment with corticosteroid-resistant DRESS syndrome.

Drug-Induced Hypersensitivity Syndrome (DIHS)/Drug Reaction With Eosinophilia and Systemic Symptoms (DRESS): Clinical Features and Pathogenesis

Drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms (DIHS/DRESS) is one example of a severe delayed T-cell-mediated adverse drug reaction. DIHS/DRESS presents with fever, widespread rash and facial edema, organ involvement, and hematological abnormalities, including eosinophilia and atypical lymphocytosis. DIHS/DRESS is associated with relapse 2 to 4 weeks after acute symptoms, often coinciding with reactivation of prevalent chronic persistent human herpesviruses such as human herpesvirus 6, EBV, and cytomegalovirus. The mortality of DIHS/DRESS is up to 10% and often related to unrecognized myocarditis and cytomegalovirus complications, with longer-term consequences that contribute to morbidity including autoimmune diseases such as thyroiditis. It is essential that all potential drug causes, including all new drugs introduced within the 8 weeks preceding onset of DIHS/DRESS symptoms, are identified. All potential drug culprits, as well as drugs that are closely related structurally to the culprit drug, should be avoided in the future. Systemic corticosteroids have remained the mainstay for the treatment of DIHS/DRESS with internal organ involvement. Steroid-sparing agents, such as cyclosporine, mycophenolate mofetil, and monthly intravenous immune globulin, have been successfully used for treatment, and careful follow-up for cytomegalovirus reactivation is recommended. Strong associations between HLA class I alleles and DIHS/DRESS predisposition include HLA-B∗13:01 and dapsone, HLA-B∗58:01 and allopurinol, and HLA-B∗32:01 and vancomycin. These have opened a pathway for prevention, risk stratification, and earlier diagnosis. Single-cell sequencing and other studies of immunopathogenesis promise to identify targeted treatment approaches.

Monocyte Signature Associated with Herpes Simplex Virus Reactivation and Neurological Recovery After Brain Injury

RATIONALE

Brain injury induces systemic immunosuppression increasing the risk of viral reactivations and altering neurological recovery.

OBJECTIVES

To determine if systemic immune alterations and lung replication of Herpesviridae are associated and can help predict outcomes after brain injury.

METHODS

We collected peripheral blood mononuclear cells in severely brain-injured patients requiring invasive mechanical ventilation. We systematically searched for respiratory Herpes Simplex Virus (HSV) replications in tracheal aspirates. We also performed CHiP-sequencing, RNA-sequencing and in vitro functional assays of monocytes and CD4 T cells collected on day 1 to characterize immune response to severe acute brain injury. The primary outcome was the Glasgow outcome scale Extended (GOS-E) at 6 months.

MEASUREMENTS AND MAIN RESULTS

In 344 severe brain-injured patients, lung HSV reactivations were observed in 39% of patients seropositive for HSV, and independently associated with poor neurological recovery at six months (hazard ratio 1.90, 95%CI 1.08-3.57). WGNA analyses of the transcriptomic response of monocytes to brain injury defined a module of 721 genes, including PD-L1 and CD80, enriched for the binding DNA motif of the transcriptional factor Zeb2, and whose ontogenic analyses revealed decreased interferon--mediated and anti-viral response signaling pathways. This monocyte signature was preserved in a validation cohort and predicted the neurological outcome at 6 months with good accuracy (AUC 0.786, 95%CI 0.593-0.978).

CONCLUSIONS

A specific monocyte signature is associated with HSV reactivation and predicts recovery after brain injury. The alterations of the immune control of Herpesviridae replication are understudied and represent a novel therapeutic target.

Drug Reaction with Eosinophilia and Systemic Symptoms (DReSS)/Drug-Induced Hypersensitivity Syndrome (DiHS)—Readdressing the DReSS

Drug reaction with eosinophilia and systemic symptoms (DReSS), also known as drug-induced hypersensitivity syndrome (DiHS), is a severe, systemic, T cell mediated drug reaction with combinations of cutaneous, hematologic, and internal organ involvement. Pathogenesis of DReSS is multi-factorial, involving drug-exposure, genetic predisposition through specific human leukocyte antigen (HLA) alleles and metabolism defects, viral reactivation, and immune dysregulation. Clinical features of this condition are delayed, stepwise, and heterogenous, making this syndrome challenging to recognize and diagnose. Two sets of validated diagnostic criteria exist that can be employed to diagnose DReSS/DiHS. Methods to improve early recognition of DReSS and predict disease severity has been a recent area of research focus. In vitro and in vivo tests can be employed to confirm the diagnosis and help identify culprit drugs. The mainstay treatment of DReSS is prompt withdrawal of the culprit drug, supportive treatment, and immunosuppression depending on the severity of disease. We present a comprehensive review on the most recent research and literature on DReSS, with emphasis on pathogenesis, clinical features, diagnosis, confirmatory testing modalities, and treatment. Additionally, this summary aims to highlight the differing viewpoints on this severe disease and broaden our perspective on the condition known as DReSS.

Drug allergy and non-HIV immune reconstitution inflammatory syndrome

Non-HIV immune reconstitution inflammatory syndrome (non-HIV IRIS) is associated with the recovery from an immunocompromised condition. It is defined as inflammatory disorders caused by antigens, including drugs or pathogenic microorganisms present prior to immune recovery, or by the exacerbation of an inflammatory disorder that was already present. Drug-induced hypersensitivity syndrome is a prototype of IRIS, and the pathophysiology of non-HIV IRIS can be recognized in several disorders treated with corticosteroids, immunosuppressants, molecular-targeted drugs, TNF-α antibody drugs, immune checkpoint inhibitors, and dipeptidyl peptidase-4 inhibitors. This review focuses on the relationship between the immune mechanism of non-HIV IRIS and drug allergies, especially severe drug eruption. The antigen recognition mechanism in drug allergy varies depending on the clinical type and the causative drug. The p-i concept is the main mechanism in severe drug eruption such as Stevens-Johnson syndrome/toxic epidermal necrolysis, and drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms. Lymphocytes activated by an antigen other than a drug, such as a virus, can also develop drug allergy by the loose binding of drugs with immune receptors of T cells or human leukocyte antigen. Therefore, fluctuations in the immune environment affect the onset of severe drug eruption. Novel agents that cause major changes in immunity have been marketed mainly for autoimmune diseases and malignant tumors; therefore, it is necessary to consider their effects when treating severe drug eruptions. Moreover, although a list of diagnostic criteria for this syndrome has been drafted, predictive and diagnostic biomarkers for this syndrome needs to be urgently developed.

Drug reaction with eosinophilia and systemic symptoms: An emergency medicine focused review

INTRODUCTION

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe drug reaction associated with potentially severe morbidity and mortality.

OBJECTIVE

This narrative review evaluates the pathogenesis, diagnosis, and management of DRESS for emergency clinicians.

DISCUSSION

DRESS is a severe hypersensitivity reaction which can involve multiple organ systems, including the skin, lymphatic system, lungs, kidneys, and heart. Treatment is primarily supportive care combined with removal of the offending agent and initiation of corticosteroids. Additional options include cyclophosphamide, cyclosporine, intravenous immunoglobulin, and N-acetylcysteine.

CONCLUSION

It is important for the emergency clinician to be aware of the diagnosis and management of DRESS in order to best optimize care for these patients.

The important role of non-covalent drug-protein interactions in drug hypersensitivity reactions

Drug hypersensitivity reactions (DHR) are heterogeneous and unusual immune reactions with rather unique clinical presentations. Accumulating evidence indicates that certain non‐covalent drug‐protein interactions are able to elicit exclusively effector functions of antibody reactions or complete T‐cell reactions which contribute substantially to DHR. Here, we discuss three key interactions; (a) mimicry: whereby soluble, non‐covalent drug‐protein complexes (“fake antigens”) mimic covalent drug‐protein adducts; (b) increased antibody affinity: for example, in quinine‐type immune thrombocytopenia where the drug gets trapped between antibody and membrane‐bound glycoprotein; and (c) p‐i‐stimulation: where naïve and memory T cells are activated by direct binding of drugs to the human leukocyte antigen and/or T‐cell receptors. This transient drug‐immune receptor interaction initiates a polyclonal T‐cell response with mild‐to‐severe DHR symptoms. Notable complications arising from p‐i DHR can include viral reactivations, autoimmunity, and multiple drug hypersensitivity. In conclusion, DHR is characterized by abnormal immune stimulation driven by non‐covalent drug‐protein interactions. This contrasts DHR from “normal” immunity, which relies on antigen‐formation by covalent hapten‐protein adducts and predominantly results in asymptomatic immunity.

Serum Soluble OX40 as a Diagnostic and Prognostic Biomarker for Drug-Induced Hypersensitivity Syndrome/Drug Reaction with Eosinophilia and Systemic Symptoms

BACKGROUND

Drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms (DIHS/DRESS) is a severe adverse drug reaction commonly associated with the reactivation of human herpesvirus 6 (HHV-6). There are currently no adequate biomarkers for the early diagnosis and detection of DIHS/DRESS. Notably, OX40 (CD134) has an important role in allergic inflammation and functions as a cellular receptor for HHV-6 entry. We previously reported that the membrane-bound form of OX40 in CD4⁺ T cells was upregulated in DIHS/DRESS.

OBJECTIVE

We sought to investigate the clinical significance of serum soluble OX40 (sOX40) in DIHS/DRESS.

METHODS

Serum sOX40 levels in patients with DIHS/DRESS (n = 39), maculopapular exanthema/erythema multiforme (n = 17), Stevens-Johnson syndrome/toxic epidermal necrolysis (n = 13), or autoimmune bullous diseases (n = 5), and levels in healthy volunteers (n = 5) were examined by enzyme-linked immunosorbent assay. Copy numbers of HHV-6, HHV-7, and cytomegalovirus in peripheral blood mononuclear cells were quantified using real-time PCR.

RESULTS

Serum sOX40 levels in patients with DIHS/DRESS in the acute stage were elevated in parallel with high OX40 expression on CD4⁺ T cells. Serum sOX40 levels were significantly positively correlated with disease severity and serum levels of thymus and activation-regulated chemokine, IL-5, and IL-10. Human herpesvirus 6-positive patients had higher sOX40 levels than did HHV-6-negative patients, and serum sOX40 levels were correlated with HHV-6 DNA loads.

CONCLUSIONS

Serum sOX40 levels can be a useful diagnostic marker for DIHS/DRESS that reflect disease severity. Elevated serum sOX40 levels also predict HHV-6 reactivation in patients with DIHS/DRESS.

Successful mepolizumab treatment for DRESS-induced refractory eosinophilic myocarditis and concurrent thyroiditis

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a potentially life-threatening adverse drug reaction with a mortality rate of 10%. Interstitial nephritis, pneumonitis, myocarditis, meningitis, thyroiditis and pancreatitis are major causes of morbidity and mortality in this syndrome. Cessation of offending medication is paramount. There is paucity in high quality prospective studies guiding the treatment of DRESS, and there are no published therapeutic clinical trials in the treatment of corticosteroid refractory hypersensitivity myocarditis. The authors present a unique case of ciprofloxacin-induced DRESS with concurrent thyroiditis and refractory eosinophilic myocarditis that required mepolizumab and multiple immunosuppressants for successful treatment.

The Emerging Role of the Innate Immune Response in Idiosyncratic Drug Reactions

Idiosyncratic drug reactions (IDRs) range from relatively common, mild reactions to rarer, potentially life-threatening adverse effects that pose significant risks to both human health and successful drug discovery. Most frequently, IDRs target the liver, skin, and blood or bone marrow. Clinical data indicate that most IDRs are mediated by an adaptive immune response against drug-modified proteins, formed when chemically reactive species of a drug bind to self-proteins, making them appear foreign to the immune system. Although much emphasis has been placed on characterizing the clinical presentation of IDRs and noting implicated drugs, limited research has focused on the mechanisms preceding the manifestations of these severe responses. Therefore, we propose that to address the knowledge gap between drug administration and onset of a severe IDR, more research is required to understand IDR-initiating mechanisms; namely, the role of the innate immune response. In this review, we outline the immune processes involved from neoantigen formation to the result of the formation of the immunologic synapse and suggest that this framework be applied to IDR research. Using four drugs associated with severe IDRs as examples (amoxicillin, amodiaquine, clozapine, and nevirapine), we also summarize clinical and animal model data that are supportive of an early innate immune response. Finally, we discuss how understanding the early steps in innate immune activation in the development of an adaptive IDR will be fundamental in risk assessment during drug development. SIGNIFICANCE STATEMENT: Although there is some understanding that certain adaptive immune mechanisms are involved in the development of idiosyncratic drug reactions, the early phase of these immune responses remains largely uncharacterized. The presented framework refocuses the investigation of IDR pathogenesis from severe clinical manifestations to the initiating innate immune mechanisms that, in contrast, may be quite mild or clinically silent. A comprehensive understanding of these early influences on IDR onset is crucial for accurate risk prediction, IDR prevention, and therapeutic intervention.

Viral Infections and Cutaneous Drug-Related Eruptions

In the general population, up to 10% of children treated by antibiotics have cutaneous adverse drug reaction, but allergy is confirmed in less than 20% of patients. Most of the non-allergic reactions are probably due to virus, such as enterovirus acute infection or Ebstein-Barr Virus (EBV) acute infection or reactivation. Especially in children, viruses have the propensity to induce skin lesions (maculopapular rash, urticaria) due to their skin infiltration or immunologic response. In drug-related skin eruptions, a virus can participate by activating an immune predisposition. The culprit antibiotic is then the trigger for reacting. Even in severe drug-induced reactions, such as Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) syndrome, viruses take part in immune phenomena, especially herpes viruses. Understanding the mechanisms of both virus- and drug-induced skin reaction is important to develop our clinical reflection and give an adaptive care to the patient. Our aim is to review current knowledge on the different aspects and potential roles of viruses in the different type of drug hypersensitivity reactions (DHR). Although major advances have been made those past year, further studies are needed for a better understanding of the link between viruses and DHR, to improve management of those patients.

Current Perspective Regarding the Immunopathogenesis of Drug-Induced Hypersensitivity Syndrome/Drug Reaction with Eosinophilia and Systemic Symptoms (DIHS/DRESS)

Drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms (DIHS/DRESS) is a severe type of adverse drug eruption associated with multiorgan involvement and the reactivation of human herpesvirus 6, which arises after prolonged exposure to certain drugs. Typically, two waves of disease activity occur during the course of DIHS/DRESS; however, some patients experience multiple waves of exacerbation and remission of the disease. Severe complications, some of which are related to cytomegalovirus reactivation, can be fatal. DIHS/DRESS is distinct from other drug reactions, as it involves herpes virus reactivation and can lead to the subsequent development of autoimmune diseases. The association between herpesviruses and DIHS/DRESS is now well established, and DIHS/DRESS is considered to arise as a result of complex interactions between several herpesviruses and comprehensive immune responses, including drug-specific immune responses and antiviral immune responses, each of which may be mediated by distinct types of immune cells. It appears that both CD4 and CD8 T cells are involved in the pathogenesis of DIHS/DRESS but play distinct roles. CD4 T cells mainly initiate drug allergies in response to drug antigens, and then herpesvirus-specific CD8 T cells that target virus-infected cells emerge, resulting in tissue damage. Regulatory T-cell dynamics are also suggested to contribute to the diverse symptoms of DIHS/DRESS. However, the pathomechanisms of this complex disease remain largely unknown. In particular, how viral infections contribute to the pathogenesis of DIHS/DRESS and why autoimmune sequelae arise in DIHS/DRESS are yet to be elucidated. This review describes the clinical features of DIHS/DRESS, including the associated complications and sequelae, and discusses recent advances in our understanding of the immunopathogenic mechanisms of DIHS/DRESS.

Drug Reaction with Eosinophilia and Systemic Symptoms: A Complex Interplay between Drug, T Cells, and Herpesviridae

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome, also known as drug induced hypersensitivity (DiHS) syndrome is a severe delayed hypersensitivity reaction with potentially fatal consequences. Whilst recognised as T cell-mediated, our understanding of the immunopathogenesis of this syndrome remains incomplete. Here, we discuss models of DRESS, including the role of human leukocyte antigen (HLA) and how observations derived from new molecular techniques adopted in key studies have informed our mechanism-based understanding of the central role of Herpesviridae reactivation and heterologous immunity in these disorders.

Updates and Insights in the Diagnosis and Management of DRESS Syndrome

PURPOSE OF REVIEW

To provide updates on recent advances in the diagnosis and management of drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome.

RECENT FINDINGS

The number of identified HLA allele associations with DRESS continues to grow. There is increasing evidence indicating viral infection, reactivation, and cross-reactivity may play key roles in disease. Translational work illuminated JAK/STAT activation in recalcitrant disease. There is expanding recognition of rapid-onset DRESS resulting from specific drugs.

SUMMARY

DRESS is a severe form of adverse drug reaction with potential for significant morbidity and mortality. Recent research advances may improve clinical care. HLA screening can now be performed to prevent disease in susceptible patients and may help identify culprit drugs in the near future. Viral testing should be performed on every patient, and if positive, patients potentially treated with antiviral therapy. JAK inhibitors may be an effective treatment option for DRESS. Early onset of disease relative to drug exposure should not exclude the diagnosis of DRESS.

Agranulocytosis-complicated DRESS with medullar HHV-6 replication

HHV-6B is the subtype most often involved in the systemic manifestations of the DRESS, but also in myelosuppression in bone marrow transplant. We report a new observation of its myelosuppressive effect: a case of DRESS complicated by agranulocytosis with detectable HHV-6 RNA in bone marrow.

A clinical and histological comparison between acute cutaneous graft-versus-host disease and other maculopapular eruptions following hematopoietic stem cell transplantation: a retrospective cohort

BACKGROUND

Prompt management of acute graft-versus-host disease (GVHD) may prevent its morbidity and mortality. Maculopapular (MP) eruption is a presenting sign of acute GVHD, but differentiation from other causes of MP rash is challenging.

METHODS

A retrospective study was conducted among patients developing MP eruptions after allogeneic hematopoietic stem cell transplantation. We compared the clinical and histopathological differences between an acute cutaneous GVHD (group 1) and other MP eruptions (group 2). We also determined the clinical prognostic indicators linked to acute GVHD severity, morbidity, and mortality.

RESULTS

Of 95 patients identified, 75 met the classification criteria for acute GVHD, and 25 had other MP eruptions. Palm and/or sole involvement was more frequently found (51.4% vs. 12%, odds ratio [OR] [95% confidence interval] = 7 [2.1, 23.7], P < 0.01 and 41.4% vs. 0%, OR 37.2 [2.2, 635], P < 0.01, respectively) in group 1 than in group 2. Comparing the histological features between the two groups, necrotic keratinocytes in basal and spinous layers (92.9% vs. 22.2%, OR 27 [3.5, 594.7], P < 0.01) and (85.7% vs. 33.3%, OR 9.3 [1.4, 60.8], P = 0.02, respectively), diffuse basal vacuolization (42.9% vs. 0%, OR 14.5 [0.7, 298.2], P = 0.04), lymphocyte satellitosis (71.4% vs. 0%, OR 44.3 [2.1, 936.8], P < 0.01), and subepidermal clefts (42.9% vs. 0%, OR 14.5 [0.7, 298.2], P = 0.04) were significantly more apparent in group 1. Among extracutaneous presentations, diarrhea alone and/or accompanied by hyperbilirubinemia (47.1% vs. 16%, OR 4.3 [1.4, 13.1], P = 0.03 and 27.1% vs. 0%, OR 19.3 [1.1, 332.8], P < 0.01, respectively) and newly developed transaminitis (37.1% vs. 12%, OR 3.3 [1.1, 12.6], P = 0.02) suggested the diagnosis of acute GVHD. Mucosal involvement and/or blister formation correlated with severe acute GVHD (OR 26.6 [5.4, 130.4], P < 0.01). Skin and systemic GVHD severity correlated with time to rash resolution (P = 0.03 and P = 0.04, respectively), length of hospital stays (P < 0.01 and P < 0.01, respectively), and mortality (OR 4.87 [1.4, 17.4], P = 0.02 and OR 4.6 [1.3, 16.5], P = 0.02, respectively).

CONCLUSIONS

Our findings may be beneficial tools for establishing the diagnosis of acute GVHD.

Drug Reaction with Eosinophilia and Systemic Symptoms Secondary to Naproxen: A Case Report and Literature Review

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a severe adverse drug reaction presenting with rash, fever, lymphadenopathy, and single or multiple organ involvement. It is most commonly associated with antiepileptics, NSAIDs, and sulfa drugs. We report a 40-year-old man who presented with a 1-week history of fever, sore throat, and a diffuse pruritic macular rash that started on the face and trunk before spreading to all extremities 4 weeks after the use of naproxen. He had lymphadenopathy, hepatosplenomegaly, transaminitis, and peripheral eosinophilia. A Registry of Severe Cutaneous Adverse Reactions (RegiSCAR) score of 8 gave a diagnosis of definite DRESS syndrome. Significant resolution of symptoms and laboratory abnormalities were seen after 2 weeks of corticosteroid therapy. DRESS syndrome is a life-threatening condition, and the clinical status of patients can worsen rapidly. Given the high variability in clinical presentation, the diagnosis of DRESS syndrome requires a high degree of suspicion and clinical judgment. Case reports on this entity will equip physicians in acute medicine to recognize and treat the condition early. This report reinforces the importance of using the RegiSCAR score in the diagnosis of DRESS syndrome.

Pediatric drug eruptions

Drug eruptions in children are common but in general less studied than their adult counterparts. Aside from having significant impact on the child's health and quality of life, these reactions can limit what medications the patient can receive in the future. Familiarity with pediatric drug eruptions is important for accurate diagnosis and to prevent future recurrence or ineffective therapy. Our current understanding of how drug reactions differ mechanistically between children and adults is poor. There are multiple factors that could be contributing to the differing incidence, presentation, and treatment modalities offered to pediatric versus adult patients. For many of these cutaneous drug reactions, the treatment regime is not standardized, being based primarily on case reports. Although not comprehensive, this review highlights common pediatric drug eruption patterns and discuss diagnostic mimickers. Five cutaneous adverse drug reactions in the pediatric population are presented: morbilliform (exanthematous) eruptions, urticarial eruptions, serum sickness-like reactions, fixed drug eruptions, and DRESS syndrome. Clinical features, diagnostic workup, and management are discussed with an emphasis on the pediatric population.

Drug-Induced liver Injury Associated with Severe Cutaneous Hypersensitivity Reactions: A Complex Entity in Need of a Multidisciplinary Approach

Idiosyncratic drug-induced liver injury (DILI) occasionally occurs in the setting of severe cutaneous adverse reactions (SCARs), including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN) and drug reaction with eosinophilia and systemic symptoms (DRESS). This strengthens the proposed immunologic mechanism associated with this adverse reaction. DRESS exhibits the most common association with DILI. SCARs have a wide spectrum of heterogeneous clinical presentations and severity, and genetic predisposition has been identified. In the context of SCARs, DILI present a different clinical picture, ranging from mild injury to acute liver failure. Elucidating the role of DILI in the clinical presentation and outcome of SCARs represents a challenge due to limited information from published studies and the lack of consensus on definitions. The cholestatic and mixed pattern of liver damage typically predominates in the case of DILI associated with SCARs, which is different from DILI without SCARs where hepatocellular is the most common injury pattern. Only a few drugs have been associated with both DILI and SCARs. Is this article, the criteria used for DILI recognition among SCARS have been revised and discussed, along with the drugs most commonly involved in these syndromes as well as the outcome, prognostic factors and the need for a multidisciplinary approach to improve the management of DILI in the context of SCARs.

Readmission Risk Factors and Complications in Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are mucocutaneous hypersensitivity reactions that cause necrosis of the epidermis, often at multiple sites. This process is frequently caused by medications and is associated with significant complications and mortality during hospitalization. However, increasing attention has been drawn to the less studied area of post-hospitalization complications leading to multiple readmissions. We present a patient diagnosed with trimethoprim-sulfamethoxazole induced SJS/TEN, who was readmitted within one week with sepsis. We also discuss the readmission risk factors and post-hospitalization features and complications of SJS/TEN.

Influence of corticosteroid therapy on viral reactivation in drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms

Drug‐induced hypersensitivity syndrome (DIHS)/drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe adverse drug reaction characteristically associated with sequential reactivation of herpesviruses, such as human herpesvirus 6 (HHV‐6), Epstein‐Barr virus (EBV), and cytomegalovirus (CMV). Since systemic corticosteroids are thought to result in viral reactivation due to their immunosuppressive effects, we clarified the influence of systemic corticosteroid therapy on viral reactivation in DIHS/DRESS. Viral DNA in peripheral whole blood and serum sIL‐2R level were measured during the disease course in twenty DIHS/DRESS patients. Six of seven patients treated without corticosteroids experienced HHV‐6 viremia associated with elevated serum sIL‐2R levels. In contrast, high‐dose corticosteroids started within 1 week after onset tended to inhibit the occurrence of HHV‐6 reactivation with remarkable suppression of serum sIL‐2R level. Low‐dose corticosteroids or late‐start high‐dose corticosteroids did not suppress occurrence of HHV‐6 viremia and the increase of sIL‐2R levels. HHV‐6 load in the blood was clearly correlated with the serum sIL‐2R level. On the other hand, increased CMV load were found in patients treated with corticosteroids regardless of the start time. The frequency of detection of EBV DNA in peripheral blood was similarly observed in all groups. In conclusion, high‐dose corticosteroids started within 1 week tended to suppress HHV‐6 reactivation through suppression of T cell activation. However, CMV proliferation was promoted by corticosteroids regardless of the start time. These observations suggested that careful consideration should be given to the dose and timing of administration of systemic corticosteroids in the treatment of DIHS/DRESS.

Mechanisms of Severe Cutaneous Adverse Reactions: Recent Advances

Cutaneous adverse drug reactions are unpredictable and include various different skin conditions of varying degrees of severity. The most concerning are usually referred to as severe cutaneous adverse reactions (SCARs) and include acute generalized exanthematous pustulosis (AGEP), drug reaction with eosinophilia and systemic symptoms (DRESS), also known as drug-induced hypersensitivity syndrome (DiHS) or hypersensitivity syndrome (HSS), Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). All are delayed type IV hypersensitivity reactions in which a T-cell-mediated drug-specific immune response is responsible for causing the disease. Nonetheless, specific T-cell subpopulations develop in response to certain environmental conditions and produce cytokines that orchestrate the various phenotypes. Cytotoxic T lymphocytes (CTLs), T-helper type 1 (Th1), Th2, Th17, and regulatory T cells (Treg), among other T-cell subpopulations, participate in the development of SCAR phenotypes. Cell subpopulations belonging to the innate immune system, comprising natural killer cells, innate lymphoid cells, monocytes, macrophages and dendritic cells, can also participate in shaping specific immune responses in various clinical conditions. Additionally, tissue-resident cells, including keratinocytes, can contribute to epidermal damage by secreting chemokines that attract pro-inflammatory immunocytes. The final phenotypes in each clinical entity result from the complex interactions between a variety of cell lineages, their products, soluble mediators and genetic and environmental factors. Although the pathophysiology of these reactions is not fully understood, intensive research in recent years has led to major progress in our understanding of the contribution of certain cell types and soluble mediators to the variability of SCAR phenotypes.

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.

The rash that presents as a red swollen face

A red swollen face can be a skin sign of a potentially life-threatening condition. We present in detail the main clinical presentations, diagnostic tests, and management of some of the most severe conditions that can frequently present as a red and swollen face: acute or recurrent angioedema, mast cell-driven or bradykinin-mediated angioedema, nonhereditary and hereditary angioedema, allergic or photoallergic facial contact dermatitis, contact urticaria, severe adverse drug reactions (particularly drug reaction with eosinophilia and systemic symptoms [DRESS]), skin infections (erysipelas, cellulitis, necrotizing fasciitis), and autoimmune diseases (dermatomyositis). There are many other conditions that also have to be considered in the differential diagnosis of a red swollen face.

A case of drug-induced hypersensitivity syndrome induced by salazosulfapyridine combined with SIADH caused by interstitial pneumonia

We present a case of a patient with drug-induced hypersensitivity syndrome (DIHS) caused by salazosulfapyridine combined with syndrome of inappropriate secretion of antidiuretic hormone (SIADH) caused by interstitial pneumonia (IP). A 67-year-old man with a past history of rheumatism (RA) presented with right hemiparalysis and aphasia as the chief complaints. A diagnosis of left embolic cerebral infarction following trial therapy for RA based on computed tomography findings was made, and external decompression was performed. Salazosulfapyridine was newly started on day 7. Dabigatran was started on day 37. On day 41, the patient developed fever. On day 42, edema and erythema appeared on his face, and erythema and rash appeared on his trunk and extremities, with gradual transition to erythroderma. The drug eruption was initially attributed to the dabigatran. Various symptoms of organ dysfunction (enteritis, myocarditis, interstitial pneumonia, hepatic disorder, stomatitis, and others) then appeared and persisted; hence, a diagnosis of DIHS associated with human herpes virus 6 and cytomegalovirus infection induced by salazosulfapyridine was suggested, and the oral administration of salazosulfapyridine was discontinued on day 53. Hyponatremia was observed in association with exacerbation of IP. Due to low serum osmotic pressure and prompt improvement of the serum sodium level by fluid restriction, the SIADH was attributed to IP. In this case, steroid pulse therapy followed by gradual decrease therapy prevented worsening of the condition.

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.

Drug-induced hypersensitivity syndrome (DiHS)/drug reaction with eosinophilia and systemic symptoms (DRESS): An update in 2019

The aim of this review was to provide an updated overview of drug-induced hypersensitivity syndrome (DiHS)/drug reaction with eosinophilia and systemic symptoms (DRESS). Several new insights have been made, particularly with regards to the diagnosis, pathogenesis and care of some important complications and sequelae. The indication of herpesvirus reactivations in diagnosis in the assessment of disease severity is now better specified. Nevertheless, because fatal complications and autoimmune sequelae have been under-recognized, there is a clear need to identify effective parameters for assessing disease severity and predicting prognosis of the disease in the early phase. In this regard, we have established a scoring system that can be used to monitor severity, predict prognosis and stratify the risk of developing severe complications including fatal cytomegalovirus (CMV) disease. Regulatory T cells are likely to be central to the mechanism and would represent potential targets for therapeutic approaches that can ameliorate inflammatory responses occurring at the acute phase while preventing the subsequent development of harmful outcomes, such as CMV disease and autoimmune diseases.

Drug reaction with eosinophilia and systemic symptoms in pediatric patients: A clinicopathological study of 16 cases in the National Center of Pharmacovigilance of Tunisia

INTRODUCTION

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe cutaneous adverse drug reaction (SCAR) that can affect the pediatric population. However, data on its characteristics in this age group are limited. This study aims to evaluate clinical and pathological features of cases of DRESS in children reported to the national center of pharmacovigilance of Tunisia.

METHODS

We conducted a descriptive retrospective study on the cases of children with DRESS reported to the National Center of Pharmacovigilance of Tunisia between January 2011 and December 2017. We used for the diagnostic the criteria suggested by the European Registry of Severe Cutaneous Adverse Reactions (RegiSCAR).

RESULTS

There were 16 patients with a diagnosis of DRESS. Mean age was six years. The most common offending drugs were anticonvulsants (68.75%). The mean latency period from using the culprit drug to the onset of drug reaction was 21 days. Skin lesions and internal organ involvement were present in all patients. Hepatitis was the most common visceral involvement. Eosinophilia (>1500 cells/μL) was present in 10 patients (62.5%). The outcome was favorable for all patients after drug withdrawal and symptomatic treatment.

CONCLUSION

Clinical features of DRESS in Tunisian children provide clinical information that could be useful for the early detection and the outcome improvement of this severe adverse reaction.