Herpes simplex virus associated erythema multiforme (HAEM) is mechanistically distinct from drug-induced erythema multiforme: interferon-gamma is expressed in HAEM lesions and tumor necrosis factor-alpha in drug-induced erythema multiforme lesions

Exploring the association between erythema multiforme and HIV infection: some mechanisms and implications

Erythema multiforme (EM) is an immune-mediated mucocutaneous condition characterized by hypersensitivity reactions to antigenic stimuli from infectious agents and certain drugs. The most commonly implicated infectious agents associated with EM include herpes simplex virus (HSV) and Mycoplasma pneumoniae. Other infectious diseases reported to trigger EM include human immunodeficiency virus (HIV) infection and several opportunistic infections. However, studies focusing on EM and human immunodeficiency virus (HIV) infection are scarce. even though the incidence of EM among HIV-infected individuals have increased, the direct and indirect mechanisms that predispose HIV-infected individuals to EM are not well understood. In turn, this makes diagnosing and managing EM in HIV-infected individuals an overwhelming task. Individuals with HIV infection are prone to acquiring microorganisms known to trigger EM, such as HSV, Mycobacterium tuberculosis, Treponema pallidum, histoplasmosis, and many other infectious organisms. Although HIV is known to infect CD4 + T cells, it can also directly bind to the epithelial cells of the oral and genital mucosa, leading to a dysregulated response by CD8 + T cells against epithelial cells. HIV infection may also trigger EM directly when CD8 + T cells recognize viral particles on epithelial cells due to the hyperactivation of CD8 + T-cells. The hyperactivation of CD8 + T cells was similar to that observed in drug hypersensitivity reactions. Hence, the relationship between antiretroviral drugs and EM has been well established. This includes the administration of other drugs to HIV-infected individuals to manage opportunistic infections. Thus, multiple triggers may be present simultaneously in HIV-infected individuals. This article highlights the potential direct and indirect role that HIV infection may play in the development of EM and the clinical dilemma that arises in the management of HIV-infected patients with this condition. These patients may require additional medications to manage opportunistic infections, many of which can also trigger hypersensitivity reactions leading to EM.

Case Report: Erythema Multiforme Induced by Lithium Contact

Erythema multiforme (EM) is an acute, self-limited mucocutaneous disease with diverse triggering factors, and the recurrences are quite common. A 24-year old male presented with multiple erythematous, itchy papules and plaques on multiple sites. He has worked in a lithium battery factory and experienced the chemical burn 2 weeks ago. A histopathologic examination on right wrist showed a scattered lymphocytic infiltration, vacuolar degeneration, and necrotic keratinocyte. The final diagnosis was EM after occupational lithium exposure. He was treated by oral methylprednisolone and experienced recurrences after returning to the same workplace after remission. Although the precise pathogenesis is unknown, the pathogenesis of EM by lithium is related to the effect of lithium on immune system, different from other etiologies. To our knowledge, our case is the first report of EM following the chemical burn and occupational lithium exposure. We report this as an interesting case of EM.

Supportive care and antiviral treatments in primary herpetic gingivostomatitis: a systematic review

OBJECTIVES

Herpes simplex virus 1 (HSV-1) is the main pathogen responsible for herpes infections. In 13-30% of the cases, primary HSV-1 leads to the primary herpetic gingivostomatitis (PHGS), often a self-limiting infection; however, it can limit the ability to drink/eat with, sometimes, the need for hospitalization. Multiple therapeutic methods have been proposed. This systematic review aims to collect and critically appraise the available evidence about the clinical management of PHGS.

MATERIALS AND METHODS

Literature search including three databases (PubMed, Scopus, Embase), study design, and data analysis were performed following PRISMA guidelines, according to the PICO tool (PROSPERO n° CRD42023391386). Risk of bias was assessed with RoB 2 and ROBINS-I.

RESULTS

Five studies on a total of 364 patients (average age: 7.6 years) were identified. The treatment regimens were summarized in acyclovir; acyclovir + honey; fluids and analgesic; maalox + diphenhydramine; lidocaine; chlorhexidine (CHX); CHX + ialuronic acid; CHX + Mucosyte®; antimicrobial photodynamic therapy (aPDT); topical antiviral; topical antiviral + aPDT; and others.

CONCLUSIONS

Although PHGS is a disease with a high worldwide prevalence, the lack of consensus about therapeutic management indicates gaps in existing evidence. Most of the proposed treatment consists in symptomatic drugs with empiric regimens which are ineffective for the viral replication. The main limit to realize randomized clinical trial is due to the rapid onset and remission of the disease. In fact, the diagnostic delay, estimated in 72 h, decreases the effectiveness of any antiviral drugs.

CLINICAL RELEVANCE

Out of the five studies included in this systematic review, only one was able to provide some weak evidence that ACV is an effective treatment, improving healing of oral lesions and reducing duration of symptoms.

Roles of Mast Cells in Cutaneous Diseases

Mast cells are present in all vascularized tissues of the body. They are especially abundant in tissues that are in frequent contact with the surrounding environment and act as potential sources of inflammatory and/or regulatory mediators during development of various infections and diseases. Mature mast cells’ cytoplasm contains numerous granules that store a variety of chemical mediators, cytokines, proteoglycans, and proteases. Mast cells are activated via various cell surface receptors, including FcϵRI, toll-like receptors (TLR), Mas-related G-protein-coupled receptor X2 (MRGPRX2), and cytokine receptors. IgE-mediated mast cell activation results in release of histamine and other contents of their granules into the extracellular environment, contributing to host defense against pathogens. TLRs, play a crucial role in host defense against various types of pathogens by recognizing pathogen-associated molecular patterns. On the other hand, excessive/inappropriate mast cell activation can cause various disorders. Here, we review the published literature regarding the known and potential inflammatory and regulatory roles of mast cells in cutaneous inflammation, including atopic dermatitis, psoriasis, and contact dermatitis GVHD, as well as in host defense against pathogens.

Treatment of Persistent Erythema Multiforme With Janus Kinase Inhibition and the Role of Interferon Gamma and Interleukin 15 in Its Pathogenesis

IMPORTANCE

Persistent erythema multiforme (PEM) is poorly understood and lacks effective therapies other than glucocorticoids.

OBJECTIVE

To report outcomes following treatment of PEM with Janus kinase (JAK) inhibition and to elucidate cytokine drivers of erythema multiforme (EM).

DESIGN, SETTING, AND PARTICIPANTS

This was a retrospective case series of 4 patients with PEM treated with tofacitinib and/or upadacitinib in 2015 to 2021 at the dermatology clinics of 2 major tertiary referral centers. Four consecutive patients with PEM refractory to multiple treatment approaches were treated. In 1 patient, skin biopsy specimens were obtained for RNA sequencing and proteomic analysis before and during treatment. Molecular findings were validated through RNA in situ hybridization analysis of cytokine expression in biopsy specimens from a total of 12 patients with EM (3 treated with tofacitinib in this study and 9 historic samples).

INTERVENTIONS

Treatment with tofacitinib, 5 to 10 mg, twice daily or upadacitinib, 15 mg, once daily.

MAIN OUTCOMES AND MEASURES

Change in PEM activity was assessed in all 4 patients treated with a JAK inhibitor. Median (range) follow-up was 20.5 months (10.0-36.0 mo).

RESULTS

The study population of 4 female patients had a mean (SD) age of 46.2 (13.7) years and a mean (SD) disease duration of 21.75 (11.30) years. Marked clinical improvement was noted in all 4 patients. In 1 patient with a robust improvement following treatment with tofacitinib, RNA sequencing identified interferon gamma (IFN-γ) and interleukin 15 (IL-15) as cytokines with activity both highly upregulated at baseline in lesional skin and subsequently suppressed following tofacitinib treatment. Measurement of IFNG- and IL15-positive cells in additional EM biopsy specimens of 12 patients showed significant upregulation of IFNG (8.72 cells per mm; 95% CI, 2.60-14.84) and IL15 (14.13 cells per mm; 95% CI, 0.14-28.11) compared with normal skin (P = .008 and P = .045, respectively).

CONCLUSIONS AND RELEVANCE

The results of this case series study suggest that JAK inhibition may be effective in treating PEM and that IFN-γ and IL-15 may be important cytokine mediators of the disease.

Herpes Simplex Associated Erythema Multiforme: A Case Report and Review of the Literature

Erythema multiforme (EM) is an acute immune-mediated disease with multifactor etiology, which presents with symmetric target-like lesions on the skin. Probably the most common etiological factor of EM is viral infections, particularly herpes simplex virus (HSV). Herpes-associated erythema multiforme (HAEM) is an acute exudative dermatosis, caused mostly by HSV-1 and much rarely by HSV-2. A 44-year-old female patient with herpes associated erythema multiforme was consulted with initial appearance of typical target lesions on the dorsal surface of both hands, after long history of labial herpes episodes. The diagnostic algorithm included routine laboratory tests, histological examination and serologic test for HSV-1 and 2. Our first choice of treatment was acyclovir 5 x 200 mg/24 h and dexamethasone 4 mg/24 h, however due to increased anxiety and tachycardia reported by patient the corticosteroid therapy was discontinued and promethazine was initiated. The patient responded well to the therapeutic regimen and at the follow-up visit was in clinical remission. In conclusion, the diagnosis of HAEM is mainly clinical, when the patient develops target lesions and coexisting HSV infection is detected.

Recent Updates in the Treatment of Erythema Multiforme

Erythema multiforme (EM) is an immune-mediated condition that classically presents with discrete targetoid lesions and can involve both mucosal and cutaneous sites. While EM is typically preceded by viral infections, most notably herpes simplex virus (HSV), and certain medications, a large portion of cases are due to an unidentifiable cause. EM can be confused with other more serious conditions like Stevens–Johnson syndrome (SJS); however, clinical research has provided significant evidence to classify EM and SJS as separate disorders. Treatment of EM is highly variable, depending on the etiology, the involvement of mucosal sites, and the chronicity (acute vs. recurring) of the disease. If the etiology or causal medication/infection is identified, then the medication is stopped and/or the infection is treated prior to initiating symptomatic treatment. Treatment for acute EM is focused on relieving symptoms with topical steroids or antihistamines. Treatment for recurrent EM is most successful when tailored to individual patients. First line treatment for recurrent EM includes both systemic and topical therapies. Systemic therapies include corticosteroid therapy and antiviral prophylaxis. Topical therapies include high-potency corticosteroids, and antiseptic or anesthetic solutions for mucosal involvement. Second-line therapies for patients who do not respond to antiviral medications include immunosuppressive agents, antibiotics, anthelmintics, and antimalarials

Oral Manifestations of Exudative Erythema Multiforme in a Patient with COVID-19

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a viral infection with multiorgan manifestations that may affect the oral mucosa. The full range of oral manifestations of COVID-19 are unknown, and there are limited reports describing the features of oral manifestations of COVID-19, including taste loss, oral lesions, and xerostomia. The aim of this study is to report a case of oral erythema multiforme (EM) manifesting as oral, lip, and skin lesions in a COVID-19 patient. The presence of oral lesions in the late stage of COVID-19 could be related to weak patient immunity or related therapies.

Recurrent erythema multiforme: A therapeutic proposal for a chronic disease

Recurrent erythema multiforme is a chronic relapsing disease that represents a therapeutic challenge. Our objective was to retrospectively evaluate the clinical-epidemiological characteristics and therapeutic response of patients with recurrent erythema multiforme and suggest a therapeutic protocol. We included patients with recurrent erythema multiforme diagnosed between January 2000 and December 2019. Clinical symptoms and a positive serology for herpes simplex virus were the inclusion criteria to initiate acyclovir in monotherapy or a combined treatment with dapsone, thalidomide, or immunosuppressants in refractory cases. Thirty-five patients were included and 71.4% were female. The median disease onset age was 35.7 years and the mean follow-up was 7.58 years. The skin was the most affected site (91.4%). Herpes simplex virus immunoglobulin (Ig)G serology was positive in 91.1% of cases. Acyclovir treatment was used in 33 of 35 patients, and complete remission was achieved in 22 of 33 after the first therapeutic course; 16 of 22 relapsed and required a second acyclovir cycle. Combined treatment with dapsone was required in nine of 33 due to partial response to acyclovir; thalidomide was an adjuvant drug in four of 33 due to adverse effects to dapsone. After the first cycle of acyclovir with or without combined therapy, 19 of 33 patients relapsed and received 2-6 additional cycles. Our results suggest that recurrent erythema multiforme presents a good response to acyclovir in monotherapy or in combined therapy with dapsone or thalidomide in the majority of patients. We propose a long-term therapeutic protocol to enable disease remission.

Altered levels of complement components associated with non-immediate drug hypersensitivity reactions

Nonimmediate drug hypersensitivity reactions (niDHRs) range from mild-type maculopapular exanthema (MPE) to severe type Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) with unentirely clarified pathogenesis. This study sought to explore whether complement components participated in niDHRs. The participants comprised of three groups as follows: MPE (n = 65), SJS/TEN (n = 13, contains 7 SJS, 2 SJS-TEN overlap and 4 TEN), and equal healthy controls (n = 78). Skin pathological changes were confirmed by hematoxylin and eosin staining. The mRNA and protein levels of complement components were assessed. In the MPE group, there were no alterations in complement components at the protein and mRNA levels found except for a decrease in factor H mRNA. In the SJS/TEN group, up-regulated levels of C3aR and C5aR mRNA and down-regulated factor H mRNA levels in blood were noted. A lower plasma protein level of C3, Factor H and a higher level of C3a, C5, C5a, C5b-9, Factor B (p < 0.05) were found in the SJS/TEN group compared with in the control (p < 0.05). In SJS/TEN skin lesions, indirect immunofluorescence assays showed positive specific staining for C5b-9, but not C3. Both C3aR and C5aR were positive staining in the SJS/TEN samples, while staining for C1q, mannose-binding lectin (MBL), Factor B, and Factor H were only weak or negative. The findings reported here are the first to define the expression profiles/extent of the presence of various complement components at the mRNA and protein levels in niDHRs, especially in SJS/TEN. These altered complement components might, at least in part, be integral to the mechanisms underlying the pathogeneses of SJS and TEN.

Oral Mucosal Injury Caused by Targeted Cancer Therapies

Targeted cancer therapies have fundamentally transformed the treatment of many types of cancers over the past decade, including breast, colorectal, lung, and pancreatic cancers, as well as lymphoma, leukemia, and multiple myeloma. The unique mechanisms of action of these agents have resulted in many patients experiencing enhanced tumor response together with a reduced adverse event profile as well. Toxicities do continue to occur, however, and in selected cases can be clinically challenging to manage. Of particular importance in the context of this monograph is that the pathobiology for oral mucosal lesions caused by targeted cancer therapies has only been preliminarily investigated. There is distinct need for novel basic, translational, and clinical research strategies to enhance design of preventive and therapeutic approaches for patients at risk for development of these lesions. The research modeling can be conceptually enhanced by extrapolating "lessons learned" from selected oral mucosal conditions in patients without cancer as well. This approach may permit determination of the extent to which pathobiology and clinical management are either similar to or uniquely distinct from oral mucosal lesions caused by targeted cancer therapies. Modeling associated with oral mucosal disease in non-oncology patients is thus presented in this context as well. This article addresses this emerging paradigm, with emphasis on current mechanistic modeling and clinical treatment. This approach is in turn designed to foster delineation of new research strategies, with the goal of enhancing cancer patient treatment in the future.

Topical Imiquimod and Subsequent Erythema Multiforme

Topical imiquimod is commonly used in the nonsurgical management of actinic keratosis and superficial basal cell carcinoma. Although adverse effects have been limited primarily to local irritation, another rare adverse reaction is erythema multiforme. We present a case of erythema multiforme involving the oral mucosa, trunk, and extremities that followed broad application of topical imiquimod for the management of suspected superficial basal cell skin cancers and actinic keratosis. The patient had used imiquimod previously without complication. Cessation of use and systemic corticosteroids resulted in prompt clearance.

Old dog begging for new tricks: current practices and future directions in the diagnosis of delayed antimicrobial hypersensitivity

PURPOSE OF REVIEW

Antimicrobials are a leading cause of severe T cell-mediated adverse drug reactions (ADRs). The purpose of this review is to address the current understanding of antimicrobial cross-reactivity and the ready availability of and evidence for in-vitro, in-vivo, and ex-vivo diagnostics for T cell-mediated ADRs.

RECENT FINDINGS

Recent literature has evaluated the efficacy of traditional antibiotic allergy management, including patch testing, skin prick testing, intradermal testing, and oral challenge. Although patch and intradermal testing are specific for the diagnosis of immune-mediated ADRs, they suffer from drug-specific limitations in sensitivity. The use of ex-vivo diagnostics, especially enzyme-linked immunospot, has been highlighted as a promising new approach to assigning causality. Knowledge of true rates of antimicrobial cross-reactivity aids empirical antibiotic choice in the setting of previous immune-mediated ADRs.

SUMMARY

In an era of increasing antimicrobial resistance and use of broad-spectrum antimicrobial therapy, ensuring patients are assigned the correct 'allergy label' is essential. Re-exposure to implicated antimicrobials, especially in the setting of severe adverse cutaneous reaction, is associated with significant morbidity and mortality. The process through which an antibiotic label gets assigned, acted on and maintained is still imprecise. Predicting T cell-mediated ADRs via personalized approaches, including human leukocyte antigen-typing, may pave future pathways to safer antimicrobial prescribing guidelines.

Erythema Multiforme Associated with Respiratory Disease in a Commercial Breeding Pig Herd

This study describes an erythema multiforme (EM) in breeding sows, after their mixing in the group housing system. Sows at 30-35 days of gestation showed red and raised skin areas, depression, anorexia, fever, respiratory problems, and increased return to estrus. Blood and nasal samples from diseased sows were examined by quantitative polymerase chain reaction and enzyme-linked immunosorbent assay for respiratory pathogens. Hematological and biochemical analyses were performed on the blood samples. From diseased sows, vaginal swabs for microbiological examinations and samples at slaughterhouse for gross and microscopic examinations were collected. Samples from the complete gestation and lactation feed were examined for mycotoxins. All sampled sows were seropositive for Actinobacillus pleuropneumoniae (App) and porcine reproductive and respiratory syndrome virus (PRRSV). No viremia for PRRSV and porcine circovirus type 2 were detected. All nasal samples were positive for Streptococcus suis, one for Swine Influenza Virus and one for App, Hemophilus parasuis, and S. suis. In all vaginal swabs, Escherichia coli and Streptococcus spp. were detected. Diseased sows had moderate leukocytosis, mild anemia, and thrombocytopenia. No mycotoxins were detected in feed. Histopathological examination revealed increased vascularization of the superficial and middle dermis. EM was likely due to illness caused by viral and bacterial infections. This study suggests that stress caused by the sows' mixing might have triggered the problem.

Oral mucosal manifestations of autoimmune skin diseases

A group of autoimmune diseases is characterised by autoantibodies against epithelial adhesion structures and/or tissue-tropic lymphocytes driving inflammatory processes resulting in specific pathology at the mucosal surfaces and the skin. The most frequent site of mucosal involvement in autoimmune diseases is the oral cavity. Broadly, these diseases include conditions affecting the cell-cell adhesion causing intra-epithelial blistering and those where autoantibodies or infiltration lymphocytes cause a loss of cell-matrix adhesion or interface inflammation. Clinically, patients present with blistering, erosions and ulcers that may affect the skin as well as further mucosal surfaces of the eyes, nose and genitalia. While the autoimmune disease may be suspected based on clinical manifestations, demonstration of tissue-bound and circulating autoantibodies, or lymphocytic infiltrates, by various methods including histological examination, direct and indirect immunofluorescence microscopy, immunoblotting and quantitative immunoassay is a prerequisite for definitive diagnosis. Given the frequency of oral involvement and the fact that oral mucosa is the initially affected site in many cases, the informed practitioner should be well acquainted with diagnostic and therapeutic aspects of autoimmune dermatosis with oral involvement. This paper reviews the pathogenesis and clinical presentation of these conditions in the oral cavity with a specific emphasis on their differential diagnosis and current management approaches.

Drug induced erythema multiforme: two case series with review of literature

Erythema Multiforme, (EM) an uncommon, acute inflammatory reactive mucocutaneous disorder and primary allergies confined to the oral mucosa. However the subsequent attacks can produce more severe forms of EM involving the skin. Manifestations of EM are varied and present a diagnostic dilemma because infections (particularly herpes simplex and mycoplasma pneumoniae) and drugs seem to predispose towards development of EM. We report two cases of EM in which drugs (Dioclofenac sodium & Amoxycilline) seems to be precipitating factor. In addition, the article reviews various aspects of EM as relevant to dental practice and highlight the associated potential etiologic agents, pathogenic mechanisms and therapies.

Expression of interleukin-17 in lesions of erythema multiforme may indicate a role for T helper 17 cells

Introduction

The aim of this study was to evaluate levels of interleukin (IL)-2, IL-6, IL-8, IL-10, IL-17A and interferon γ (IFN-γ) in the serum of patients with erythema multiforme (EM) and to search for the presence of IL-17-expressing cells in lesional samples of EM.

Material and methods

A total of 32 patients (22 females and 10 males) diagnosed with EM of the minor or major type were included in the study. Levels of IL-2, IL-6, IL-8, IL-10, IL-17A and IFN-γ in the serum were determined and compared with healthy controls. Biopsy specimens were stained with haematoxylin and eosin (HE) and monoclonal antibodies to CD4, CD8 and IL-17 for immunohistochemical examination.

Results

IL-2, 6, 8 and 17A were significantly higher in the patient group (p = 0.016, p = 0.001, p = 0.004, p = 0.006, respectively) and levels of IL-10 were significantly lower than in the control group (p = 0.046). The cellular infiltrate in lesions of EM was composed mainly of CD4+ T lymphocytes. The presence of IL-17-expressing cells, at proportion of 5 to 50%, was observed in the infiltrate.

Conclusions

The demonstration of IL-17-expressing cells in lesions of EM in this study has brought forth the assumption that Th17 cells may be involved in the pathogenesis of EM.

Drug induced erythema multiforme: two case series with review of literature

Erythema Multiforme, (EM) an uncommon, acute inflammatory reactive mucocutaneous disorder and primary allergies confined to the oral mucosa. However the subsequent attacks can produce more severe forms of EM involving the skin. Manifestations of EM are varied and present a diagnostic dilemma because infections (particularly herpes simplex and mycoplasma pneumoniae) and drugs seem to predispose towards development of EM. We report two cases of EM in which drugs (Dioclofenac sodium & Amoxycilline) seems to be precipitating factor. In addition, the article reviews various aspects of EM as relevant to dental practice and highlight the associated potential etiologic agents, pathogenic mechanisms and therapies.

Erythema multiforme, Stevens-Johnson syndrome and toxic epidermal necrolysis: a comparative review

BACKGROUND

Human erythema multiforme (EM) and Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) are separate conditions. There is no consensus on classification criteria for the eponymous diseases in animals.

RESULTS

Animal EM is very different from 90% of human EM, which is herpes virus associated (HAEM). Animals lack acrally distributed, typical raised targets. Unlike canine parvovirus 'EM', HAEM is not an active infection. Animal EM is often attributed to drugs, but this is rarely proved. Conversely, human and animal SJS/TEN are almost identical, life-threatening disorders of epidermal necrosis and detachment, typically triggered by drugs (occasionally by infectious agents). Both EM and SJS/TEN are mediated by cytotoxic lymphocyte responses against altered keratinocytes (infectious agents or drugs). Apoptosis results from direct cytotoxicity or through soluble mediators, namely Fas ligand, granzymes, perforin and granulysin. Diagnosis in humans is clinicopathological, with emphasis on clinical lesions; histopathology confirms the pathological process as interface (cytotoxic) dermatitis. Human EM is self-limiting; only recurrent and rare persistent cases require antiviral/immunosuppressive therapies. Drug-induced EM responds to drug withdrawal. Idiopathic canine EM (>40%) is usually chronic, refractory to treatment and may represent heterogeneous conditions. Early identification and removal of the causative drug and high-quality supportive care are critical in SJS/TEN. Mortality rate is nevertheless high.

CONCLUSIONS AND CLINICAL IMPORTANCE

(1) Histopathological lesions do not reliably differentiate EM, SJS and TEN. (2) A multicentre study to develop a consensus set of clinical criteria for EM and SJS/TEN in animals is overdue. (3) No adjunctive therapies, including intravenous immunoglobulin and ciclosporin, have met evidence-based standards.

Acute skin graft-versus-host disease with molecular features mimicking herpes simplex virus-associated erythema multiforme: report of three cases

BACKGROUND

Acute skin erythematous lesions that follow allogeneic hematopoietic stem cell transplantation (HSCT) and are histologically diagnosed as graft-versus-host disease (GVHD) are often associated with reactivation of latent herpes simplex virus (HSV).

OBJECTIVE

To further examine the relationship between reactivated HSV and GVHD development.

METHODS

We present 3 patients with acute skin GVHD after allogeneic HSCT who were studied prospectively for expression of the HSV antigen Pol, which is involved in HSV-associated erythema multiforme.

RESULTS

Pol was expressed in the GVHD lesions but not the pre-HSCT normal skin or peripheral blood mononuclear cells. Lesion severity correlated with the Pol levels but not the histopathologically defined GVHD grade. Lesion development was accompanied by increased numbers of Pol+ circulating/skin-infiltrating CD34+ stem cells and CD1a+ and other dermal dendritic cells.

CONCLUSIONS

Subclinical HSV infection of circulating CD34+ cells can contribute to some post-HSCT skin lesions histologically diagnosed as GVHD, with potential preventive and therapeutic implications.

Photodistributed erythema multiforme

Although the existence of photodistributed erythema multiforme has been recognized for years, few cases have been described to date. It is an uncommon, and probably underdiagnosed, skin disorder that can affect individuals of both sexes and all ages. It has been associated with drugs, reactivation of herpes simplex virus infection, and polymorphous light eruption. A diagnosis is made on the basis of history, physical examination, histology, and phototesting. The condition runs a benign, self-limiting course but patients may experience outbreaks for several years if the causative agent is not eliminated. It is treated symptomatically and patients are advised to avoid triggers and excessive sun exposure.

Herpes associated erythema multiforme

Erythema multiforme is an acute and a self-limiting mucocutaneous hypersensitivity reaction triggered by certain infections and medications. One of the most common predisposing factors for erythema multiforme is infection with herpes simplex virus. Herpes associated erythema multiforme (HAEM) is an acute exudative dermatic and mucosal disease caused by the infecting herpes simplex virus. It has recurrence and idiorestriction, characterized by increasing of CD4+T leukomonocyte. This article reports a case of HAEM in a 9-year-old girl, with a review of relevant literature, and discusses the pathophysiology and treatment of erythema multiforme triggered by herpes simplex virus

Oral mucosal diseases: the inflammatory dermatoses

The oral inflammatory dermatoses is a term used to describe a number of predominantly immune-mediated disorders: lichen planus (LP), erythema multiforme (EM), the vesiculobullous diseases pemphigoid (MMP), pemphigus (PV) and epidermolysis bullosa acquisita (EBA). These conditions are characterized by frequent involvement of the oral mucosa and often associated with extraoral manifestations, particularly of the skin, but can involve the eyes, both the conjunctiva and sclera, the nasal and pharyngeal mucosa, as well as the genitals. Given their frequent, and sometimes initial involvement of the oral mucosa, oral health professionals need to be both familiar with the clinical features and presentations of these conditions, and appreciate their critical role in management. This paper reviews the clinical features and presentation of the oral dermatoses, provides guidance as to the appropriate investigations needed to differentiate and correctly diagnose these conditions, details the aetio-pathology of these diseases and discusses their management.

Anticytokine therapy, particularly anti-IFN-gamma, in Th1-mediated autoimmune diseases

Anticytokine therapy was proposed in 1974 in Nature, in which it was stated that hyperproduced interferon can cause autoimmune disease and anti-interferon can be therapeutic. In 1989, the use of antibodies to tumor necrosis factor-alpha in combination with antibodies to certain types of interferon was proposed to treat various autoimmune diseases, including AIDS. The first anticytokine therapy was conducted in 1975. Anti-interferon-gamma has brought improved and often striking results in the treatment of various T-helper 1-mediated autoimmune diseases, including inflammatory skin diseases. Anti-interferon-gamma may be a universal treatment for these conditions. In AIDS and other virus-induced autoimmune diseases, the virus may stimulate cytokines (interferons), which increase, rather than halt, viral replication. Tumor necrosis factor-alpha inhibitors have also shown good clinical results, however, they may result in complications and are ineffective in some autoimmune diseases.

Acute skin eruptions that are positive for herpes simplex virus DNA polymerase in patients with stem cell transplantation: a new manifestation within the erythema multiforme reactive dermatoses

BACKGROUND

Patients with stem cell transplantation (SCT) develop erythematous eruptions (SCTE) that are often misdiagnosed and poorly treated. Latent herpes simplex virus (HSV) is likely to be reactivated by SCT-associated immunosuppression. Therefore, one of the differential diagnostic possibilities for SCTE is HSV-associated erythema multiforme (HAEM) in which HSV genetic fragments localize in stem cells that deliver them to the skin on differentiation.

OBSERVATIONS

Lesional skin from patients with SCTE, HAEM, HSV, or drug-induced erythema (DIEM) was stained with antibodies to the HSV antigen DNA polymerase (Pol) and the major capsid protein, virion protein 5 (VP5). The HSV DNA polymerase Pol was expressed in 79% of patients with SCTE and 75% of those with HAEM. The protein VP5 was not expressed in these patients, indicative of the absence of virus replication. Findings in patients with DIEM were negative for both antigens, and those with HSV lesions were positive for both antigens.

CONCLUSIONS

There is a growing problem with SCTE, related to the increasing numbers of performed SCT. The greater frequency of SCT-generated circulating stem cells in patients with hematological malignant neoplasms (who have latent HSV infection) may result in a widespread SCTE characterized by skin deposition of HSV DNA fragments, notably those expressing Pol antigen. This HAEM-like presentation should be considered in the differential diagnosis of SCTE. Prolonged high-dosage antiviral chemotherapy during and after hospitalization may be warranted.

Herpes Simplex Virus Type 1 infection: overview on relevant clinico-pathological features

Herpes Simplex Virus Type 1 (HSV-1) is a nuclear replicating enveloped virus, usually acquired through direct contact with infected lesions or body fluids (typically saliva). The prevalence of HSV-1 infection increases progressively from childhood, the seroprevalence being inversely related to socioeconomic background. Primary HSV-1 infections in children are either asymptomatic or following an incubation period of about 1 week gives rise to mucocutaneous vesicular eruptions. Herpetic gingivostomatitis typically affects the tongue, lips, gingival, buccal mucosa and the hard and soft palate. Most primary oro-facial HSV infection is caused by HSV-1, infection by HSV-2 is increasingly common. Recurrent infections, which occur at variable intervals, typically give rise to vesiculo-ulcerative lesions at mucocutaneous junctions particularly the lips (herpes labialis). Recurrent HSV-1 infection within the mouth is uncommon in otherwise healthy patients, although in immunocompromised patients, recurrent infection can be more extensive and/or aggressive. The diagnosis of common herpetic infection can usually be based upon the clinical history and presenting features. Confirmatory laboratory diagnosis is, however, required when patients are, or may be, immunocompromised.

The Herpes simplex virus gene Pol expressed in herpes-associated erythema multiforme lesions upregulates/activates SP1 and inflammatory cytokines

BACKGROUND/AIMS

Herpes-simplex-virus-associated erythema multiforme (HAEM) is characterized by lesional skin expression of the viral protein Pol and localized inflammation. The objective of this study is to examine the mechanism whereby Pol induces localized inflammation.

METHODS

A431 cells transfected with Pol or an empty vector and lesional skin from HAEM or drug-induced erythema multiforme patients were examined for expression of the transcription factor SP1 and SP1-regulated genes by immunoblotting, immunohistochemistry and immunofluorescence.

RESULTS

SP1, TGF-beta, p21(waf1) and Hsp27 were upregulated in A431 cells transfected with Pol but not the empty vector. Expression was further increased by exposure to IFN-gamma. Pol+ HAEM lesional skin expressed SP1, Hsp27, TGF-beta and p21(waf1). Normal skin and drug-induced erythema multiforme lesional skin were negative.

CONCLUSION

The data indicate that Pol activates SP1, causing upregulation of SP1 target genes (notably TGF-beta) involved in localized inflammation. Upregulation is potentiated by IFN-gamma.

Serum levels of the Th1 promoter IL-12 and the Th2 chemokine TARC are elevated in erythema multiforme and Stevens-Johnson syndrome/toxic epidermal necrolysis and correlate with soluble Fas ligand expression. An immunoenzymatic study from the Italian Group of Immunopathology

BACKGROUND

No data exist as to Th2 chemokines in erythema multiforme (EM) and Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN).

OBJECTIVE

To evaluate thymus- and activation-regulated chemokine (TARC), macrophage-derived chemokine (MDC) and regulated upon activation, normal T-lymphocyte-expressed and secreted chemokine (RANTES) expression in EM and SJS/TEN and to correlate with the serum levels of the Th1 promoter interleukin (IL)-12 and soluble Fas ligand (sFasL).

MATERIALS AND METHODS

IL-12, sFasL, TARC, MDC and RANTES expression were analyzed by ELISA techniques in 31 untreated EM (n = 24) or SJS/TEN (n = 7) patients and in 28 healthy donors (HD).

RESULTS

EM and SJS/TEN exhibited significantly higher levels of TARC, IL-12 and sFasL with respect to HD. TARC upregulation paralleled both the IL-12 (p = 0.0225) and sFasL increase (p = 0.0194).

CONCLUSIONS

Our results support a role of TARC in the pathophysiology of EM/SJS/TEN and confirm the coexistence of a Th2 response in addition to the predominant Th1 profile.

Management of recurrent oral herpes simplex infections

The literature has been reviewed for evidence of the efficacy of antiviral agents in both the prophylaxis and treatment of recurrent oral herpes simplex virus (HSV) infections and discussed by a panel of experts. Emphasis was given to randomized controlled trials. Management of herpes-associated erythema multiforme and Bell palsy were also considered. The evidence suggests that 5% acyclovir (ACV) in the cream base may reduce the duration of lesions if applied early. Recurrent herpes labialis (RHL) and recurrent intraoral HSV infections can be effectively treated with systemic ACV 400 mg 3 times a day or systemic valacyclovir 500 to 1000 mg twice a day for 3 to 5 days (longer in the immunocompromised). RHL in the immunocompetent can be effectively prevented with (1) sunscreen alone (SPF 15 or above), (2) systemic ACV 400 mg 2 to 3 times a day, or (3) systemic valacyclovir 500 to 2000 mg twice a day. Valacyclovir 500 mg twice a day is also effective in suppressing erythema multiforme triggered by HSV. Further studies are needed to compare treatment efficacy between topical penciclovir, docosanol, and ACV cream for RHL.

Erythema multiforme and related disorders

Erythema multiforme (EM) and related disorders comprise a group of mucocutaneous disorders characterized by variable degrees of mucosal and cutaneous blistering and ulceration that occasionally can give rise to systemic upset and possibly compromise life. The clinical classification of these disorders has often been variable, thus making definitive diagnosis sometimes difficult. Despite being often caused by, or at least associated with, infection or drug therapy, the pathogenic mechanisms of these disorders remain unclear, and as a consequence, there are no evidence-based, reliably effective therapies. The present article reviews aspects of EM and related disorders of relevance to oral medicine clinical practice and highlights the associated potential etiologic agents, pathogenic mechanisms and therapies.

Expression of cytokines and chemokine receptors in the cutaneous lesions of erythema multiforme and Stevens-Johnson syndrome/toxic epidermal necrolysis

BACKGROUND

Erythema multiforme (EM) and Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) are caused by a dysregulation of cellular immunity.

OBJECTIVES

To evaluate further the potential role of certain cytokines and chemokine receptors in cutaneous lesions of patients affected by EM and SJS/TEN and to establish whether such diseases are polarized preferentially towards a T-helper (Th) 1 or Th2 pattern.

METHODS

Biopsy specimens from eight patients with EM, six with SJS/TEN and three healthy controls were stained for immunohistochemical examination using the alkaline phosphatase-antialkaline phosphatase method. The monoclonal antibodies used included those to tumour necrosis factor (TNF)-alpha, interferon (IFN)-gamma, interleukin (IL)-2, IL-5, IL-13, receptor 3 for C-C chemokines (CCR3), receptor 3 for C-x-C chemokines (CXCR3) and CXCR4.

RESULTS

The SJS/TEN specimens showed significantly higher expression of all the cytokines and chemokine receptors (except CXCR3) tested than the EM specimens. Both lesional series showed significantly higher expression of all the receptors tested than the healthy control specimens, with the sole exception of a lower expression of CCR3 in EM specimens. Comparison between molecules associated with a Th1 or Th2 response revealed a predominance of Th1 response in EM and no significant imbalance between Th1 and Th2 in SJS/TEN.

CONCLUSIONS

We have provided further evidence that TNF-alpha is strongly expressed in SJS/TEN lesions and therefore it may be involved in the epidermal necrosis featured in such diseases. IFN-gamma may play an important role both in EM and SJS/TEN. IL-2, IL-5 and IL-13 may contribute to the cutaneous immunoinflammation in these diseases. Chemokine receptors may be involved strongly in the recruitment of inflammatory cells in lesional skin. In our cases we found a sharp polarization towards a Th1 pattern in EM, while the SJS/TEN lesions showed a mixed Th1/Th2 pattern.

Toxic epidermal necrolysis

Toxic epidermal necrolysis (TEN) is an unpredictable, life-threatening drug reaction associated with a 30% mortality. Massive keratinocyte apoptosis is the hallmark of TEN. Cytotoxic T lymphocytes appear to be the main effector cells and there is experimental evidence for involvement of both the Fas-Fas ligand and perforin/granzyme pathways. Optimal treatment for these patients remains to be clarified. Discontinuation of the offending drug and prompt referral to a burn unit are generally agreed upon steps. Beyond that, however, considerable controversy exists. Evidence both pro and con exists for the use of IVIG, systemic corticosteroid, and other measures. There is also evidence suggesting that combination therapies may be of value. All the clinical data, however, is anecdotal or based on observational or retrospective studies. Definitive answers are not yet available. Given the rarity of TEN and the large number of patients required for a study to be statistically meaningful, placebo controlled trials are logistically difficult to accomplish. The absence of an animal model further hampers research into this condition. This article reviews recent data concerning clinical presentation, pathogenesis and treatment of TEN.

LEARNING OBJECTIVES

At the conclusion of this learning activity, participants should have acquired a more comprehensive knowledge of our current understanding of the classification, clinical presentation, etiology, pathophysiology, prognosis, and treatment of TEN.

The CD40/CD40 ligand system is expressed in the cutaneous lesions of erythema multiforme and Stevens-Johnson syndrome/toxic epidermal necrolysis spectrum

BACKGROUND

Erythema multiforme (EM) and Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) are determined by a dysregulation of cellular immunity.

OBJECTIVES

To evaluate the effector role of cellular immunity and the involvement of the CD40/CD40 ligand (CD40L) system in the pathogenesis of EM and SJS/TEN.

METHODS

Biopsy specimens from eight patients with EM and six with SJS/TEN were stained for immunohistochemical examination using the alkaline phosphatase/antialkaline phosphatase method. The monoclonal antibodies used included those to CD1a, CD4, CD8, CD40, CD40L, CD68, Fas, Fas ligand (FasL) and myeloperoxidase.

RESULTS

The cellular infiltrate in both EM and SJS/TEN lesions was composed mainly of T lymphocytes and CD68+ macrophages. We also detected large amounts of neutrophils. Fas and FasL were very highly expressed in SJS and TEN, but weakly in EM. CD40 staining was strong in all tissue sections; there were numerous CD40L+ cells in SJS/TEN but much fewer in EM.

CONCLUSIONS

Activated T lymphocytes and macrophages, but also neutrophils, are presumably the main triggers of mucocutaneous damage in the SJS/TEN disease spectrum. The Fas/FasL system is significantly expressed in SJS/TEN lesions, but not in EM, where this apoptotic pathway presumably does not play a pivotal role in the epidermal damage. We suggest that the CD40/CD40L system may represent an important pathway of induction of SJS/TEN lesions, while in EM it would contribute to the immunoinflammation only as a second-line mechanism.

Inhibition of IFN-gamma as a method of treatment of various autoimmune diseases, including skin diseases

We pioneered anticytokine therapy (ACT) for autoimmune diseases (ADs). In 1974, we proposed that hyperproduced interferon (IFN) can bring AD and anti-IFN can be therapeutic. In 1989, we proposed removing tumor necrosis factor (TNF)-alpha together with certain types of IFN to treat various ADs. We found IFN in patients with different ADs and conducted the first clinical trial of ACT in 1975. Anti-IFN-gamma and anti-TNF-alpha work in similar ways, but the latter brings serious complications in some patients. We obtained good, sometimes striking, therapeutic effects treating many different Th-1-mediated ADs with anti-IFN-gamma, including rheumatoid arthritis, multiple sclerosis (MS), corneal transplant rejection, and various autoimmune skin diseases such as psoriasis, alopecia areata, vitiligo, acne vulgaris, and others. Anti-IFN-gamma was in some ways superior to anti-TNF-alpha, which was ineffective in MS. Anti-IFN-gamma therapy holds great promise for treating many Th-1 ADs, especially skin diseases.