Drug reaction with eosinophilia and systemic symptoms (DRESS): a multiorgan antiviral T cell response

Drug rash with eosinophilia and systemic symptoms (DRESS) in patients receiving strontium ranelate

We have reviewed 47 drug rash with eosinophilia and systemic symptoms (DRESS) cases associated to strontium ranelate reported up to March 2011 to the Marketing Holder. The main signs were skin rash, fever, face oedema hypereosinophilia and liver involvement. For ten patients, persistence of DRESS symptoms was reported at the latest news obtained, and DRESS was identified as the direct cause of death in one case. The maximum incidence of DRESS associated with strontium ranelate was 1/24,112 [95 % CI (1/14,859; 1/42,194)] newly treated patients in France. Because DRESS is a severe drug reaction, the occurrence of a rash in a patient treated with strontium ranelate should lead to prompt and permanent treatment discontinuation.

INTRODUCTION

This study aims to describe cases of DRESS reported to the Marketing Authorisation Holder worldwide for patients receiving strontium ranelate by practitioner or by regulatory authorities.

METHODS

Spontaneously reported hypersensitivity events from the strontium ranelate pharmacovigilance database since marketing authorisation (2004) to March 2011 were reviewed by an expert committee. Cases of DRESS were classified as established, probable, possible or no DRESS according to expert judgement. National incidences of DRESS were estimated in relation to the number of newly treated patients.

RESULTS

Up to March 2011, 325 cases of strontium ranelate-induced hypersensitivity events were assessed from which 47 DRESS cases were confirmed. Mean age was 68.7 years and besides skin rash, the main signs and symptoms were hypereosinophilia, liver involvement, fever and face oedema. Median time to skin reaction was 33.5 days after treatment start. Most patients (62 %) recovered at the time of reporting or were recovering. For ten patients, persistence of DRESS symptoms was reported at the latest news obtained. Relapses were observed in a single case. The mortality rate was 8.5 %. The maximum incidence of DRESS associated with strontium ranelate was 1/24,112 [95 % CI (1/14,859; 1/42,194)] newly treated patients in France.

CONCLUSION

DRESS is a well-identified and characterised adverse reaction to strontium ranelate. This risk should be integrated in the risk-benefit balance evaluation of patient treatment, and the occurrence of a rash should lead to prompt and permanent treatment discontinuation with careful follow-up.

Prevalence of cutaneous adverse drug reactions in Southwest China: an 11-year retrospective survey on in-patients of a dermatology ward

BACKGROUND

An update of the information about the prevailing trend of cutaneous adverse drug reactions (CADRs) is important for clinicians.

OBJECTIVE

The objective of the study was to survey the prevalence of CADRs in Southwest China over the past 11 years.

METHODS

The clinical and laboratory data of all inpatients admitted with a diagnosis of CADRs to the dermatology ward of Southwest Hospital during the past 11 years were retrospectively investigated.

RESULTS

In the 547 recruited patients, the most common clinical pattern was maculopapular eruptions (n = 277), followed by fixed drug eruptions (n = 84) and acute urticaria (n = 44). In 206 cases with single medication intake, the 3 most common culprit drugs were acetaminophen (n = 44), penicillins (n = 44), and cephalosporins (n = 30). The frequency of urticaria in the elderly (≥60 years old) (n = 117) was significantly lower than that in younger patients (<60 years old) (n = 430) (P = 0.046), whereas erythema multiforme was much more common in the elderly (P = 0.038). As compared with younger patients, allopurinol was the most common culprit drug in the elderly.

CONCLUSIONS

In contrast to previous studies, our study showed that the prevalence profiles of CADRs in the elderly are quite different from those in younger population. Acetaminophen was the most common culprit drug for total CADRs, which should be alerted as an important public health problem.

Herpesviruses and the microbiome

The focus of this article will be to examine the role of common herpesviruses as a component of the microbiome of atopic patients and to review clinical observations suggesting that atopic patients might be predisposed to more severe and atypical herpes-related illness because their immune response is biased toward a TH2 cytokine profile. Human populations are infected with 8 herpesviruses, including herpes simplex virus HSV1 and HSV2 (also termed HHV1 and HHV2), varicella zoster virus (VZV or HHV3), EBV (HHV4), cytomegalovirus (HHV5), HHV6, HHV7, and Kaposi sarcoma-associated herpesvirus (termed KSV or HHV8). Herpesviruses are highly adapted to lifelong infection of their human hosts and thus can be considered a component of the human "microbiome" in addition to their role in illness triggered by primary infection. HSV1 and HSV2 infection and reactivation can present with more severe cutaneous symptoms termed eczema herpeticum in the atopic population, similar to the more severe eczema vaccinatum, and drug reaction with eosinophilia and systemic symptoms syndrome (DRESS) is associated with reactivation of HSV6 and possibly other herpesviruses in both atopic and nonatopic patients. In this review evidence is reviewed that primary infection with herpesviruses may have an atypical presentation in the atopic patient and conversely that childhood infection might alter the atopic phenotype. Reactivation of latent herpesviruses can directly alter host cytokine profiles through viral expression of cytokine-like proteins, such as IL-10 (EBV) or IL-6 (cytomegalovirus and HHV8), viral encoded and secreted siRNA and microRNAs, and modulation of expression of host transcription pathways, such as nuclear factor κB. Physicians caring for allergic and atopic populations should be aware of common and uncommon presentations of herpes-related disease in atopic patients to provide accurate diagnosis and avoid unnecessary laboratory testing or incorrect diagnosis of other conditions, such as drug allergy or autoimmune disease. Antiviral therapy and vaccines should be administered promptly when indicated clinically.

Updating the mild encephalitis hypothesis of schizophrenia

Schizophrenia seems to be a heterogeneous disorder. Emerging evidence indicates that low level neuroinflammation (LLNI) may not occur infrequently. Many infectious agents with low overall pathogenicity are risk factors for psychoses including schizophrenia and for autoimmune disorders. According to the mild encephalitis (ME) hypothesis, LLNI represents the core pathogenetic mechanism in a schizophrenia subgroup that has syndromal overlap with other psychiatric disorders. ME may be triggered by infections, autoimmunity, toxicity, or trauma. A 'late hit' and gene-environment interaction are required to explain major findings about schizophrenia, and both aspects would be consistent with the ME hypothesis. Schizophrenia risk genes stay rather constant within populations despite a resulting low number of progeny; this may result from advantages associated with risk genes, e.g., an improved immune response, which may act protectively within changing environments, although they are associated with the disadvantage of increased susceptibility to psychotic disorders. Specific schizophrenic symptoms may arise with instances of LLNI when certain brain functional systems are involved, in addition to being shaped by pre-existing liability factors. Prodrome phase and the transition to a diseased status may be related to LLNI processes emerging and varying over time. The variability in the course of schizophrenia resembles the varying courses of autoimmune disorders, which result from three required factors: genes, the environment, and the immune system. Preliminary criteria for subgrouping neurodevelopmental, genetic, ME, and other types of schizophrenias are provided. A rare example of ME schizophrenia may be observed in Borna disease virus infection. Neurodevelopmental schizophrenia due to early infections has been estimated by others to explain approximately 30% of cases, but the underlying pathomechanisms of transition to disease remain in question. LLNI (e.g. from reactivation related to persistent infection) may be involved and other pathomechanisms including dysfunction of the blood-brain barrier or the blood-CSF barrier, CNS-endogenous immunity and the volume transmission mode balancing wiring transmission (the latter represented mainly by synaptic transmission, which is often described as being disturbed in schizophrenia). Volume transmission is linked to CSF signaling; and together could represent a common pathogenetic link for the distributed brain dysfunction, dysconnectivity, and brain structural abnormalities observed in schizophrenia. In addition, CSF signaling may extend into peripheral tissues via the CSF outflow pathway along brain nerves and peripheral nerves, and it may explain the peripheral topology of neuronal dysfunctions found, like in olfactory dysfunction, dysautonomia, and even in peripheral tissues, i.e., the muscle lesions that were found in 50% of cases. Modulating factors in schizophrenia, such as stress, hormones, and diet, are also modulating factors in the immune response. Considering recent investigations of CSF, the ME schizophrenia subgroup may constitute approximately 40% of cases.

Idiosyncratic adverse drug reactions: current concepts

Idiosyncratic drug reactions are a significant cause of morbidity and mortality for patients; they also markedly increase the uncertainty of drug development. The major targets are skin, liver, and bone marrow. Clinical characteristics suggest that IDRs are immune mediated, and there is substantive evidence that most, but not all, IDRs are caused by chemically reactive species. However, rigorous mechanistic studies are very difficult to perform, especially in the absence of valid animal models. Models to explain how drugs or reactive metabolites interact with the MHC/T-cell receptor complex include the hapten and P-I models, and most recently it was found that abacavir can interact reversibly with MHC to alter the endogenous peptides that are presented to T cells. The discovery of HLA molecules as important risk factors for some IDRs has also significantly contributed to our understanding of these adverse reactions, but it is not yet clear what fraction of IDRs have a strong HLA dependence. In addition, with the exception of abacavir, most patients who have the HLA that confers a higher IDR risk with a specific drug will not have an IDR when treated with that drug. Interindividual differences in T-cell receptors and other factors also presumably play a role in determining which patients will have an IDR. The immune response represents a delicate balance, and immune tolerance may be the dominant response to a drug that can cause IDRs.

Severe DRESS syndrome managed with therapeutic plasma exchange

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a rare but increasingly described phenomenon of immune activation and organ dysfunction in association with a wide variety of medications. This reaction shows a broad spectrum of clinical presentation and severity, ranging from mild to lethal. Treatment strategies of immune suppression appear be helpful in some cases, but treatment failures occur frequently with reported mortality rates of 5% to 10%. We present a pediatric case of DRESS syndrome associated with either lamotrigine or bupropion, leading to multiorgan involvement and life-threatening complications of respiratory failure and cardiac arrest. After failing to improve with removal of these medications and administration of systemic corticosteroids, our patient showed dramatic, sustained clinical response to therapeutic plasma exchange. To our knowledge, this is the first reported case of therapeutic plasma exchange used for life-threatening DRESS syndrome in a pediatric patient. This case suggests needed research for this therapeutic option in life-threatening DRESS syndrome resistant to high-dose steroids.

[Stevens-Johnson syndrome concurrent with primary Epstein-Barr virus infection]

BACKGROUND

Primary EBV infection mainly affects children and young adults. Most patients present the characteristic triad of fever, pharyngitis and lymphadenopathy. Symptoms may include a morbilliform eruption, occasionally induced by amoxicillin. We report a case of Stevens-Johnson syndrome concurrent with EBV infection.

CASE REPORT

A 17-year-old boy consulted for an eruption suggestive of Stevens-Johnson syndrome, which was supported by the histopathology results. The patient had taken no medication during the previous weeks. Laboratory examinations showed atypical activated T lymphocytes. Serological tests and PCR results confirmed the diagnosis of primary EBV infection. The outcome was spontaneously favorable with only symptomatic treatment being required.

DISCUSSION

Stevens-Johnson syndrome is characterized by "target" lesions and profuse mucous membrane involvement. Stevens-Johnson syndrome is frequently drug-induced, being due less frequently to infections. Stevens-Johnson syndrome is very rarely a manifestation of infectious mononucleosis, with only one case being reported in the literature. When confronted with Stevens-Johnson syndrome without any imputable medication, complete screening for infection should be performed, in particular for primary EBV infection.

Drug reaction with eosinophilia and systemic symptoms syndrome associated myocarditis: a survival experience after extracorporeal membrane oxygenation support

WHAT IS KNOWN AND OBJECTIVE

Myocarditis that develops because of the drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a life-threatening disease. We report a case of DRESS-associated myocarditis with cardiac failure that required extracorporeal membrane oxygenation (ECMO) for cardiovascular support.

CASE SUMMARY

A 14-year-old boy experienced DRESS-associated myocarditis after anticonvulsive therapy with carbamazepine, clonazepam and phenytoin. The clinical signs included hypotension, cardiac arrhythmia and poor left ventricular (LV) performance. Laboratory investigations showed elevated levels of cardiac enzymes. Systemic corticosteroid pulse therapy for 3 days was administered for treating the DRESS syndrome. The patient required inotropic drugs including dopamine, dobutamine and milrinone because of refractory hypotension and poor LV function. He was placed on ECMO support, and intra-aortic balloon pumping was initiated because of poor response to inotropic drugs and stasis of blood flow in the ventricle on hospital day 17. Plasma exchanges for four separate times over 8 days were also performed during ECMO support on day 22. His condition stabilized 13 days after ECMO support was initiated. The patient was discharged on hospital day 50, and the seizure was controlled by the oral form clonazepam, phenobarbital, topiramate and levetiracetam. Three months later, an echocardiogram showed mild dilated cardiomyopathy.

WHAT IS NEW AND CONCLUSION

Drug reaction with eosinophilia and systemic symptoms-associated fulminant myocarditis is a life-threatening disease. Traditionally, systemic corticosteroid administration, plasmapheresis, intravenous immunoglobulin infusion and ventricular assist device implantation have been used for the treatment of this disease. To our knowledge, this is the first case of DRESS-associated fulminant myocarditis treated successfully with ECMO support. However, echocardiogram should be followed regularly because dilated cardiomyopathy may be the late sequela.

Antituberculosis drug-induced hypersensitivity syndrome and its association with human leukocyte antigen

Antituberculosis drug (ATD)-induced hypersensitivity syndrome (HSS) is a serious adverse reaction to ATDs, but much remains to be determined regarding its characteristics and genetic risk factors. In this study, we have collected cases of ATD-induced HSS and their clinical features, and investigated the associations of ATD-induced HSS with human leukocyte antigen (HLA). Subjects with ATD-induced HSS and ATD-tolerant controls were recruited through analysis of a multicenter adverse drug reaction registry in Korea. HLA allele frequencies were compared between subjects with ATD-induced HSS (n = 14) and two control groups: ATD-tolerant controls (n = 166) and the general population (n = 485). The number of enrolled subjects with ATD-induced HSS (n = 14) was comparable to those of patients with HSS induced by other common drugs such as allopurinol during the recruitment period. The frequency of Cw*0401 was much higher in the cases (50.0%) compared with ATD-tolerant controls (12.7%, Pc = 0.0204, OR = 6.90) and the general population (12.8%, Pc = 0.0132, OR = 6.82). Our results suggest that ATD is an important causative agent inducing HSS with distinct clinical features. The strong association of Cw*0401 with the risk for ATD-induced HSS suggests immunological involvement in the development of this syndrome.

Human leukocyte antigens (HLA) associated drug hypersensitivity: consequences of drug binding to HLA

Recent publications have shown that certain human leukocyte antigen (HLA) alleles are strongly associated with hypersensitivity to particular drugs. As HLA molecules are a critical element in T-cell stimulation, it is no surprise that particular HLA alleles have a direct functional role in the pathogenesis of drug hypersensitivity. In this context, a direct interaction of the relevant drug with HLA molecules as described by the p-i concept appears to be more relevant than presentation of hapten-modified peptides. In some HLA-associated drug hypersensitivity reactions, the presence of a risk allele is a necessary but incomplete factor for disease development. In carbamazepine and HLA-B*15:02, certain T-cell receptor (TCR) repertoires are required for immune activation. This additional requirement may be one of the 'missing links' in explaining why most individuals carrying this allele can tolerate the drug. In contrast, abacavir generates polyclonal T-cell response by interacting specifically with HLA-B*57:01 molecules. T cell stimulation may be due to presentation of abacavir or of altered peptides. While the presence of HLA-B*58:01 allele substantially increases the risk of allopurinol hypersensitivity, it is not an absolute requirement, suggesting that other factors also play an important role. In summary, drug hypersensitivity is the end result of a drug interaction with certain HLA molecules and TCRs, the sum of which determines whether the ensuing immune response is going to be harmful or not.

Human herpesviruses 6, 7, and 8 from a dermatologic perspective

Human herpesviruses (HHVs) have frequently been suspected as etiologic agents or cofactors in cutaneous disease. However, clearly established associations are rare. Investigations into an etiologic association between HHVs and cutaneous disease are complicated by the ubiquity and nearly universal prevalence of some herpesviruses. This article summarizes the associations between cutaneous disease and HHV-6, HHV-7, and HHV-8. In addition to a personal library of references, the PubMed database of biomedical literature was searched using the following Medical Subject Heading terms: HHV-6, HHV-7, and HHV-8, each in conjunction with cutaneous manifestations, virology, epidemiology, dermatopathology, and therapeutics, between 1998 and March 2011. Free-text searches with known or suspected disease associations were added for broader coverage. The results have been summarized to provide a practical review for the physician likely to encounter cutaneous diseases.

Toxic epidermal necrolysis, DRESS, AGEP: do overlap cases exist?

Background

Severe cutaneous adverse reactions to drugs (SCARs) include acute generalized exanthematous pustulosis (AGEP), drug reaction with eosinophilia and systemic symptoms (DRESS) and epidermal necrolysis (Stevens-Johnson syndrome–toxic epidermal necrolysis [SJS-TEN]). Because of the varied initial presentation of such adverse drug reactions, diagnosis may be difficult and suggests overlap among SCARs. Overlapping SCARs are defined as cases fulfilling the criteria for definite or probable diagnosis of at least 2 ADRs according to scoring systems for AGEP, DRESS and SJS-TEN. We aimed to evaluate the prevalence of overlap among SCARs among cases in the referral hospital in France.

Methods

We retrospectively analyzed data for 216 patients hospitalized in the referral centre over 7 years with a discharge diagnosis of AGEP (n = 45), DRESS (n = 47), SJS-TEN (n = 80) or “drug rash” (n = 44). Each case with detailed clinical data and a skin biopsy specimen was scored for AGEP, DRESS and SJS-TEN by use of diagnostic scores elaborated by the RegiSCAR group.

Results

In total, 45 of 216 cases (21%) had at least 2 possible diagnoses: 35 had a single predominant diagnosis (definite or probable), 7 had several possible diagnoses and 3 (2.1% of 145 confirmed SCARs) were overlap SCARs.

Conclusions

Despite ambiguities among SCARs, confirmed overlap cases are rare. This study did not avoid pitfalls linked to its retrospective nature and selection bias. In the acute stage of disease, early identification of severe ADRs can be difficult because of clinical or biologic overlapping features and missing data on histology, biology and evolution. Retrospectively analyzing cases by use of diagnostic algorithms can lead to reliable discrimination among AGEP, DRESS and SJS-TEN.

Antibiotic-associated eosinophilic and occlusive arteritis in calves complicating preclinical studies of left ventricular assist devices

Repeated bolus intravenous (IV) administration of large doses of beta-lactams and aminoglycosides has previously been associated with the development of eosinophilic and occlusive arterial lesions limited to the lungs in calves. Reviewing 13 years worth of records from left ventricular assist device implantation studies, morphologically identical segmental arterial lesions were present in 32 of the 56 calves receiving IV antibiotics, affecting lungs (6/50), kidneys (12/56), or lungs and kidneys (14/50). In 16 of these calves, renal arterial lesions spatially colocalized with renal cortical infarctions. Lesions were noted in additional abdominal organs in 4 of the 50 calves and were exclusively present in the liver in a single calf. Similar arterial lesions were also noted in the lungs (3/4), kidneys (1/4), liver (1/4), and spleen (1/4) of unimplanted calves receiving similar IV antibiotic regimens for bacterial infections. Lesions were observed with therapeutic IV doses of cephalosporins with or without aminoglycosides over shorter intervals than previously implicated. Lesions were significantly associated with increased peripheral eosinophil counts and mildly elevated, not reduced, arterial pulse pressures. This report documents the features of an idiosyncratic drug reaction with features strongly suggestive of an acute type-I hypersensitivity in this species.

Drug reaction with Eosinophilia and Systemic Symptoms (DRESS) / Drug-induced Hypersensitivity Syndrome (DIHS): a review of current concepts

The Drug Reaction with Eosinophilia and Systemic Symptoms syndrome, also known as Drug Induced Hypersensitivity Syndrome presents clinically as an extensive mucocutaneous rash, accompanied by fever, lymphadenopathy, hepatitis, hematologic abnormalities with eosinophilia and atypical lymphocytes, and may involve other organs with eosinophilic infiltration, causing damage to several systems, especially to the kidneys, heart, lungs, and pancreas. Recognition of this syndrome is of paramount importance, since the mortality rate is about 10% to 20%, and a specific therapy may be necessary. The pathogenesis is related to specific drugs, especially the aromatic anticonvulsants, altered immune response, sequential reactivation of herpes virus and association with HLA alleles. Early recognition of the syndrome and withdrawal of the offending drug are the most important and essential steps in the treatment of affected patients. Corticosteroids are the basis of the treatment of the syndrome, which may be associated with intravenous immunoglobulin and, in selected cases, Ganciclovir. The article reviews the current concepts involving this important manifestation of adverse drug reaction.

[Clomipramine hypersensitivity with predominantly pulmonary involvement]

Drug hypersensitivity (DRESS syndrome) is a rare disorder with diverse systemic and visceral manifestations. Pulmonary involvement is uncommon and is mainly characterized by eosinophilic infiltration. We report a case of DRESS syndrome induced by clomipramine with predominant pulmonary involvement.

Multiple drug hypersensitivity: normal Treg cell function but enhanced in vivo activation of drug-specific T cells

BACKGROUND

  Up to 10% of patients with severe immune-mediated drug hypersensitivity reactions have tendencies to develop multiple drug hypersensitivities (MDH). The reason why certain individuals develop MDH and the underlying pathomechanism are unclear. We investigated different T cell subpopulations in MDH patients and compared them with patients allergic to a single drug and with healthy controls (HC).

METHODS

  We analyzed the in vitro reactivity of peripheral blood mononuclear cells from MDH patients (n=7), patients with hypersensitivity to a single drug (monoallergic, n=6), and healthy controls (HD) (n=6) to various drugs (mainly antibiotics and antiepileptics). By depleting and selectively re-adding CD4(+)  CD25(bright) T cells (T regulatory cells, Treg), their effect on drug-specific T cell reactivity was analyzed. The phenotype of reacting T cells was determined ex vivo by staining for markers of activation (CD38) and cell exhaustion (PD-1).

RESULTS

  No functional deficiency of Treg cells was observed in all drug-allergic patients. Drug-reactive T cells from MDH patients were found in the CD4(+) CD25(dim) T cell fraction and showed enhanced CD38 and PD-1 expression, while those from monoallergic patients reside in the resting CD4(+)  CD25(neg) T cell fraction.

CONCLUSION

  In patients with MDH, the drug-reactive T cells are contained in an in vivo pre-activated T cell fraction. Therefore, they may show a lower threshold for activation by drugs. The reason for this in vivo T cell pre-activation needs further investigations.

Drug reaction with eosinophilia and systemic symptoms (DRESS) associated with azithromycin in acute Epstein-Barr virus infection

We report the first pediatric case of drug reaction with eosinophilia and systemic symptoms associated with azithromycin use in the setting of acute Epstein-Barr virus infection in an 8-year-old boy. Our patient presented with fever, cutaneous eruption, eosinophilia, and hypotension requiring intensive care unit admission. He was discharged in good condition without any long-term sequelae. This case underscores the importance of timely and accurate diagnosis of acute viral infections and appropriate use of antibiotics as well as recognition of the clinical signs of drug reaction with eosinophilia and systemic symptoms.

Drug hypersensitivity and human leukocyte antigens of the major histocompatibility complex

The human leukocyte antigen (HLA) genes are the most polymorphic in the human genome and are critical in regulating specific immunity, hence their historical discovery as "immune response" genes. HLA allotypes are also implicated in unwanted immune reactions, including drug hypersensitivity syndrome, in which small therapeutic drugs interact with antigenic peptides to drive T cell responses restricted by host HLA. Abacavir, allo-purinol, and carbamazepine are three commonly used drugs that cause a T cell-mediated hypersensitivity that is HLA linked, with each drug exhibiting striking specificity for presentation by defined HLA allotypes. Recent findings have begun to unearth the mechanistic basis for these HLA associations, and here we review recent advances in the field of HLA-associated drug hypersensitivities.

The DRESS syndrome: a literature review

The Drug Reaction with Eosinophilia and Systemic Symptom (DRESS) is a severe adverse drug-induced reaction. Diagnosing DRESS is challenging due to the diversity of cutaneous eruption and organs involved. We used the RegiSCAR scoring system that grades DRESS cases as "no," "possible," "probable," or "definite" to classify cases reported in the literature. We also analyzed the clinical course and treatments of the cases. A total of 44 drugs were associated with the 172 cases reported between January 1997 and May 2009 in PubMed and MEDLINE. The most frequently reported drug was carbamazepine, and the vast majority of cases were classified as "probable/definite" DRESS cases. Hypereosinophilia, liver involvement, fever, and lymphadenopathy were significantly associated with "probable/definite" DRESS cases, whereas skin rash was described in almost all of the cases, including "possible cases." Culprit drug withdrawal and corticosteroids constituted the mainstay of DRESS treatment. The outcome was death in 9 cases. However, no predictive factors for serious cases were found. This better knowledge of DRESS may contribute to improve the diagnosis and management of this syndrome in clinical practice.

[Auto-immune thyroiditis and drug reaction with eosinophilia and systemic symptoms (DRESS) associated with HHV-6 viral reactivation]

INTRODUCTION

DRESS syndrome is a severe adverse drug reaction with visceral involvement. Its physiopathology includes immunological disorders associated with human herpes virus (HHV) reactivation. We report two cases of auto-immune thyroiditis occurring in the context of DRESS syndrome associated with HHV-6 reactivation.

OBSERVATIONS

Case 1 : A 39-year-old woman presented DRESS syndrome with HHV-6 reactivation, cutaneous, lymph node, hepatic and renal disorders treated with systemic corticosteroids for 10 months. Following discontinuation of the corticosteroids, she developed Graves's disease, which was stabilized with carbimazole and a beta-blocker. CASE 2: A 31-year-old woman was hospitalized for DRESS syndrome with delayed HHV-6 reactivation and severe hepatic involvement. She was successfully treated by topical steroids. Six weeks later, she presented De Quervain thyroiditis associated with moderate relapsing DRESS, which were treated by sodium levothyroxine and topical steroids.

DISCUSSION

There is currently debate about the implication of viral reactivation, in particular HHV-6, in chronic DRESS, relapse and development of auto-immune diseases. These observations highlight the potential risk of patients developing auto-immune diseases and underline the need for prolonged clinical and laboratory follow-up of patients with DRESS.