Pustular‐type drug‐induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms due to carbamazepine with systemic muscle involvement

Drug‐induced hypersensitivity syndrome (DIHS)/drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe reaction usually associated with maculopapular eruptions and systemic involvement. Here we report the first case, to our knowledge, of DIHS/DRESS due to carbamazepine with acute generalized pustular bacterid‐like (AGPB‐like) eruptions and skeletal muscle involvement. Reviewing our case and the published work, we discuss pustular‐type DIHS/DRESS which, in most cases, involves acute generalized exanthematous pustulosis (AGEP)‐like skin eruptions in response to carbamazepine. Pustular eruptions may appear in relatively few cases of DIHS/DRESS, in particular, when the causative drug is carbamazepine and, even in cases of intractable pustular bacterid‐like eruptions, a reaction to a drug should be suspected. Skeletal muscle involvement may be associated with DIHS/DRESS as one of its systemic manifestations.     

Drug‐induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms due to lamotrigine differs from that due to other drugs

Drug‐induced hypersensitivity syndrome (DIHS), also referred to as drug reaction with eosinophilia and systemic symptoms (DRESS), is a multi‐organ systemic drug reaction characterized by hematological abnormalities and reactivation of human herpesvirus‐6 (HHV‐6). DIHS/DRESS is typically associated with a limited number of drugs, such as the anticonvulsants. Our group has treated 12 patients for DIHS/DRESS due to lamotrigine (LTG), but their presentation differed from that of patients with DIHS/DRESS caused by other drugs. The aim of the present study was to identify significant differences between DIHS/DRESS caused by LTG versus other drugs. We retrospectively reviewed data of 12 patients with DIHS/DRESS caused by LTG and 32 patients with DIHS/DRESS due to other drugs. The increase in alanine aminotransferase level was significantly milder in the LTG group than the DIHS/DRESS group due to other drugs. The percentage of atypical lymphocytes in the blood during DIHS/DRESS was lower in the LTG group. Serum levels of lactate dehydrogenase and thymus and activation‐regulated chemokine were also lower in the LTG group. There were fewer DIHS/DRESS patients with HHV‐6 reactivation in the LTG group than in the group treated with other drugs. Lymphocyte transformation after DIHS/DRESS onset was faster in the LTG group. The two groups did not differ with respect to the interval from first drug intake to rash, white blood cell count, blood eosinophilia or DRESS score. There were no significant histopathological differences between the two groups. The features of LTG‐associated DIHS/DRESS and DIHS/DRESS due to other drugs differ.     

Late-onset interstitial nephritis in a patient with drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms

Drug-induced hypersensitivity syndrome (DIHS), also referred to as drug reaction with eosinophilia and systemic symptoms (DRESS), is a severe hypersensitivity drug reaction affecting the skin and multiple internal organ systems. We report a 47-year-old man with DIHS/DRESS and comorbidities (fulminant type 1 diabetes mellitus, valsartan-induced photosensitivity, vitiligo and acute interstitial nephritis). Although acute interstitial nephritis usually appears in the early phase, his is a rare case of acute interstitial nephritis more than 2 years after the onset of DIHS/DRESS.     

Long-term outcome of patients with severe cutaneous adverse reactions

Visceral involvement associated with Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) and drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms (DIHS/DRESS) is well documented. However, little is known about the long-term outcomes of severe drug eruptions due to a lack of long-term follow-up. Long-term sequelae may arise in patients who survive the acute complications of severe drug reactions. In SJS/TEN, extensive scarring that result from the healing of mucocutaneous ulcerative lesions may interfere with organ function. Severe sequelae include visual impairment and pulmonary obliterative disease that impair patients' quality of life. In DIHS/DRESS, recent observations suggest that fulminant type 1 diabetes mellitus (FT1D) and autoimmune diseases such as autoimmune thyroiditis and lupus erythematosus can occur after a disease-free period of several months to years. Thus, DIHS/DRESS may lead to the development of autoimmune diseases, which may be overlooked. Dermatologists need to be aware of the sequelae that may arise following resolution of severe cutaneous adverse reactions and should be vigilant for manifestations of autoimmune disease during follow-up.     

Drug reaction with eosinophilia and systemic symptoms: A drug-induced hypersensitivity syndrome with variable clinical features

Drug reaction with eosinophilia and systemic symptoms (DRESS) or drug-induced hypersensitivity syndrome (DIHS) involves a unique and severe adverse drug reaction. Patients present with fever, rash, lymphadenopathy, hematological abnormalities, systemic illness, and may suffer from prolonged courses. Although the precise pathogenesis of DRESS/DIHS is not fully understood, it is widely considered to be an immunological reaction to a drug or drug metabolites. In this review article, we discuss the historical aspects of nosology, variable clinical and histopathological features, advantages and disadvantages of using an international Registry of Severe Cutaneous Adverse Reactions (RegiSCAR) and Japanese DIHS criteria, pathogenesis, treatment, and long-term sequelae of DRESS/DIHS. Early recognition of this syndrome, withdrawal of suspected culprit drugs, and adequate supportive care are mainstays of improving patient prognosis and reducing morbidities and mortality. Moreover, some DRESS/DIHS patients may develop long-term sequelae, especially autoimmune diseases and end organ failure. Physicians should be aware of these possibilities in patients after DRESS/DIHS and cautiously follow-up symptoms and laboratory tests for early detection of these sequelae.     

Syndrome of inappropriate secretion of antidiuretic hormone associated with limbic encephalitis in a patient with drug-induced hypersensitivity syndrome

Drug-induced hypersensitivity syndrome (DIHS)/drug rash with eosinophilia and systemic symptoms (DRESS) is a severe multiorgan reaction with reactivation of herpesviruses. Various features are often seen during the course of the disease. Many aspects of this syndrome suggest close similarities between DIHS/DRESS and graft-versus-host disease. We describe a patient with phenobarbital-induced hypersensitivity syndrome who revealed syndrome of inappropriate secretion of antidiuretic hormone (SIADH) associated with limbic encephalitis during the course of the disease. In view of previous reports that SIADH and limbic encephalitis are caused by reactivation of latent herpesviruses after transplantation, both conditions may be secondarily caused by reactivation of latent herpesviruses, which is typically observed in DIHS/DRESS. These neurological symptoms should be added to a growing list of important complications of DIHS/DRESS because of the high mortality rate associated with them.     

Drug‐reaction eosinophilia and systemic symptoms and drug‐induced hypersensitivity syndrome

Drug reaction with eosinophilia and systemic symptoms (DRESS), also known as drug‐induced hypersensitivity syndrome (DIHS), is a rare, severe cutaneous adverse reaction characterised by fever, rash, lymphadenopathy, eosinophilia and/or other leukocyte abnormalities, and internal organ involvement and often has a relapsing–remitting course despite withdrawal of the drug. The drugs that are most implicated include aromatic anticonvulsants, allopurinol, sulphonamides, antiretrovirals (abacavir and nevirapine), and minocycline. The pathogenesis of DRESS/DIHS is far from clear but probably involves a combination of impaired pharmacokinetics and the accumulation of drug metabolites, the sequential reactivation of the herpesvirus family and genetic susceptibility conferred by the association with certain human leukocyte antigen (HLA) class I alleles. The strong association between abacavir and HLA‐B*5701 has enabled pharmacogenetics screening to be employed successfully to minimise the occurrence of hypersensitivity. A prolonged course of oral corticosteroids is required to treat DRESS/DIHS, given the relapsing–remitting nature of the condition with i.v. immunoglobulin and valgangciclovir reserved for refractory or life‐threatening cases.     

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.     

Stevens–Johnson syndrome and toxic epidermal necrolysis due to anticonvulsants share certain clinical and laboratory features with drug‐induced hypersensitivity syndrome,despite differences in cutaneous presentations

Background. Drug‐induced hypersensitivity syndrome (DIHS)/drug rash with eosinophilia and systemic symptoms (DRESS) syndrome is characterized by late disease onset, fever, rash, hepatic dysfunction, haematological abnormalities, lymphadenopathy and often, human herpesvirus (HHV) reactivation. The diagnosis of DIHS is based on the combined presence of these findings. Anticonvulsants are a major cause of DIHS and may also cause Stevens–Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). We examined whether SJS/TEN due to anticonvulsants display similar clinical and laboratory features seen in DIHS. Methods. Patients diagnosed with SJS or TEN due to anticonvulsants (n = 8) were examined and their clinical features and laboratory findings were compared with patients with anticonvulsant‐related DIHS (n = 6). Results. Seven of the eight patients with SJS/TEN developed symptoms > 3 weeks after starting anticonvulsants. Hepatic dysfunction was present in six patients with SJS/TEN and five patients with DIHS. Leucocytosis and/or eosinophilia was noted in seven patients with SJS/TEN and four patients with DIHS. Only one patient in the SJS/TEN group had atypical lymphocytosis; this was present in four patients with DIHS. Reactivation of HHV‐6 was detected in one of the four patients tested in the SJS/TEN group, although it was seen in five of the six patients with DIHS. Conclusions. TSJS/TEN due to anticonvulsants may exhibit some clinical and laboratory features of DIHS. The nature of the cutaneous involvement should be emphasized in the diagnosis of DIHS.     

Identification of thymus and activation-regulated chemokine (TARC/CCL17) as a potential marker for early indication of disease and prediction of disease activity in drug-induced hypersensitivity syndrome (DIHS)/drug rash with eosinophilia and systemic symptoms (DRESS)

BackgroundDrug-induced hypersensitivity syndrome (DIHS)/drug rash with eosinophilia and systemic symptoms (DRESS) is a serious acute drug reaction with fever, cutaneous eruption, lymphadenopathy, and several visceral dysfunctions. Eosinophilia is a common hematological abnormality in DIHS/DRESS suggesting that the Th2-type immune response is involved. Thymus and activation-regulated chemokine (TARC/CCL17) is a family of CC chemokines known to play an important role in Th2-mediated immune-inflammatory processes.ObjectiveWe investigated the pathogenic role of TARC in patients with DIHS.MethodsSera were obtained from 8 patients with DIHS, 7 patients with Stevens–Johnson syndrome/Toxic epidermal necrolysis (SJS/TEN), and 14 patients with drug-induced maculopapular exanthema (MPE). Serum TARC levels were measured by ELISA. TARC levels were then compared with clinical symptoms and various hematological parameters. In addition, a biopsy was taken from the lesional skin of patients with DIHS and stained with anti-TARC Ab and anti-CD11c Ab.ResultsSerum TARC levels in patients with DIHS were significantly higher than those in patients with SJS/TEN and MPE during the acute phase. Serum TARC levels in DIHS patients correlated with skin eruptions, serum sIL-2R levels, eosinophil counts, and serum IL-5 levels. Immunohistochemical staining revealed that TARC was mainly expressed on CD11c+ dermal dendritic cells in patients with DIHS.ConclusionSerum TARC levels may be associated with the initial presentation of DIHS as well as disease activity during the course. Thus, they could be useful as an indicator for early diagnosis and assessment of disease activity in DIHS. CD11c+ dendritic cells may be the main source of TARC in patients with DIHS.     

Clinical and histopathological differential diagnosis of eosinophilic pustular folliculitis

Eosinophilic pustular folliculitis (EPF) is an inflammatory disease characterized by repeated pruritic follicular papules and pustules arranged in arcuate plaques, and folliculotropic infiltration of eosinophils. The diagnosis of EPF is occasionally difficult and problematic because EPF may share the clinical appearance and histological findings with other diseases. Moreover, EPF has several clinical subtypes, including the classical type, infantile type and immunosuppression‐associated type. Because the therapies of EPF are relatively specific as compared to eczematous disorders, accurate diagnosis is essential for the management of EPF. Clinical differential diagnoses include tinea, acne, rosacea, eczematous dermatitis, granuloma faciale, autoimmune annular erythema, infestations and pustular dermatosis. Histologically, cutaneous diseases with eosinophilic infiltrates can be differentially diagnosed. Follicular mucinosis, mycosis fungoides and other cutaneous T‐cell lymphomas are the most important differential diagnoses both clinically and histopathologically. It should be kept in mind particularly that the initial lesions of cutaneous T‐cell lymphoma resemble EPF.     

Case of lamotrigine‐induced drug adverse reaction under tocilizumab treatment with clinical and virological features of drug‐induced hypersensitivity syndrome

The pathological mechanisms and immunological kinetics of drug‐induced hypersensitivity syndrome (DIHS), including the relevance of interleukin (IL)‐6, remain unclear. We report a case of drug adverse reaction that does not fulfill the diagnostic criteria of DIHS but mimics its characteristic features. Because the patient was under anti‐IL‐6 therapy at the onset, some symptoms typically seen in DIHS were absent, such as fever and leukocyte count abnormalities. However, the characteristic features of DIHS were clearly observed in the subsequent course, including the repeated recurrence of skin rash, prolonged liver dysfunction and reactivation of herpes viruses. This case suggested that IL‐6 role at the onset is not a main factor to determine the subsequent pathomechanism of DIHS and attention should be paid to the preceding therapy for achieving accurate diagnosis.     

Case of vitiligo universalis as a sequela of drug‐induced hypersensitivity syndrome

Drug‐induced hypersensitivity syndrome (DIHS) is a type of severe drug adverse reaction with high morbidity and mortality. DIHS patients have been reported to subsequently develop autoimmune disease, which may be followed by end‐organ decompensation. We report a 47‐year‐old woman who presented with fever, generalized maculopapular eruption, facial edema and eosinophilia with liver function impairment after taking celecoxib and sulfasalazine for 1 month. The patient was diagnosed with definite DIHS. The patient was treated with immunosuppressants including systemic corticosteroid for approximately 1.5 years due to recurrent episodes. Reactivation of human herpesvirus 6 and possible reactivation of cytomegalovirus were detected. Generalized hypopigmentation of the skin and leukotrichia were noted 4 months after the onset of DIHS. Histopathological examination confirmed the diagnosis of vitiligo. Some spontaneous repigmentation was noted 4 years after DIHS without specific treatment. Further immunoserology study showed elevated plasma C‐X‐C motif chemokine 10 level, which is related to vitiligo activity, in our patient. The occurrence of widespread vitiligo after DIHS is an extremely rare condition. This case provides an important reminder for physicians to monitor such severe complications after DIHS.     

Ethosuximide‐induced drug reaction with eosinophilia and systemic symptoms with mediastinal lymphadenopathy

Lymphadenopathy is a common sign for drug reaction and eosinophilia with systemic symptoms (DRESS) syndrome, but hilar and mediastinal lymphadenopathy may be underreported. We describe a 7‐year‐old boy who started taking ethosuximide for absence seizures and presented with diffuse rash, fever, elevated transaminases, facial swelling, and hilar and mediastinal lymphadenopathy. His mediastinal lymphadenopathy was concerning for lymphoma, which led to more invasive testing to rule out malignancy. This report highlights an unusual and likely underreported presenting sign of DRESS syndrome in children.     

The predominant drug-specific T-cell population may switch from cytotoxic T cells to regulatory T cells during the course of anticonvulsant-induced hypersensitivity

Background

Delayed hypersensitivity is responsible for severe cutaneous adverse drug reactions (cADRs), especially in Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis, and drug-induced hypersensitivity syndrome (DIHS) (also known as drug rash with eosinophilia and systemic symptoms [DRESS] syndrome). The drug-induced lymphocyte stimulation test (DLST), or lymphocyte transformation test (LTT), is used to identify the culprit drug in severe cADR cases.

Objective

The aim of this study was to examine the immune reactions in cADR patients through the identification of the drug-specific proliferating cells by flow cytometric DLST (FCM-DLST).

Methods

The peripheral blood mononuclear cells of 16 anticonvulsant-induced cADR patients were investigated by conventional DLST and a FCM-DLST protocol in which CFSE dilution and BrdU incorporation were combined. FCM-DLST allowed for the identification of the drug-specific proliferating cells in six cases. Three of these cases were DIHS cases, whereas there was one case of SJS, one case of maculopapular rash (MP), and one case of erythema multiforme (EM) among the six cases.

Results

In FCM-DLST, drug-specific proliferating T cells were detected as CFSE^low BrdU^high cells. These cells corresponded to the cells incorporating ³H-thymidine in conventional DLST. Although CD4⁺ T-cell proliferation dominated the observed proliferation in most of the cases (in the recovery stage of the three DIHS cases, the MP case, and the EM case), drug-specific CD8⁺ cytotoxic T lymphocytes (CTLs) were detected, especially in the acute stages of the SJS case and one of the DIHS cases. There was a dramatic switch in the predominant drug-specific proliferating T-cell population in the course of one of the cases of DIHS in which CD8⁺ CTLs were predominant initially, whereas CD4⁺ T cells were predominant later. Moreover, drug-specific CD4⁺ CD25⁺ Foxp3⁺ regulatory T cells (Tregs) proliferated during the recovery stage in one DIHS case.

Conclusions

FCM-DLST revealed that the cell proliferation detected by conventional DLST is a heterogeneous proliferation of both CD8⁺ CTLs and CD4⁺ T cells that likely includes Tregs. However, the number of cADR cases in this study was limited, which limits the conclusions that can be drawn from it.     

Eosinophil-infiltrating folliculitis in childhood--report of a case

A 5-year-old Japanese girl developed follicular pustules with erythematous plaques on the lower extremities. The histopathology was compatible with eosinophilic pustular folliculitis (EPF). However, the clinical findings were not typical of EPF; the pustules did not appear in crops, the pustules became ulcers, and the skin lesions appeared exclusively on non-seborrheic areas.     

Intractable genital ulcers from herpes simplex virus reactivation in drug‐induced hypersensitivity syndrome caused by allopurinol

Background Drug‐induced hypersensitivity syndrome (DIHS/DRESS) is a severe adverse systemic reaction. Reactivation of human herpesvirus (HHV) family members other than HHV‐6 has been reported in patients with DIHS. Reactivation of HHV family members is generally characterized by increased serum antibody titers against the virus. By contrast, clinical symptoms caused by viral reactivation are relatively rare. Method We report a case of DIHS with intractable genital ulcers from reactivation of herpes simplex virus (HSV) in accordance with reactivation of HHV‐6 and cytomegalovirus (CMV). Result Twenty‐two days after the onset of the rash, the patient developed intractable genital ulcers that were resistant to treatment. Histological examination of the ulcers revealed necrotic degeneration in the epidermal cells, with giant cells containing inclusion bodies and marked lymphocytic infiltration in the upper dermis. Immunohistochemical staining with antibodies reactive to HSV or CMV showed that these giant cells were positive for HSV but negative for CMV. Conclusion Genital herpes is a common skin disease. However, our case was considered to be a DIHS‐associated symptom, not an accidental complication, as the symptoms were severe and resistant to treatment.     

Differences in immunological alterations and underlying viral infections in two well-defined severe drug eruptions

Background. Similar drugs (e.g. anticonvulsants) have been implicated in the development of two distinct forms of severe cutaneous drug reactions, Stevens–Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) and drug–induced hypersensitivity syndrome (DIHS)/drug rash with eosinophilia and systemic symptoms (DRESS). Aim. To investigate immunological alterations and underlying viral infections that could contribute to the variability in the clinical presentations of these diseases. Methods. We retrospectively analysed clinical variables, serum immunoglobulin levels, numbers of circulating white blood cells, lymphocytes and their subsets, serum levels of several cytokines, and underlying viral infections in both drug reactions, using samples obtained at onset from 9 patients with SJS/TEN and 19 patients with DIHS/DRESS. Results. There were significant differences between the two drug eruptions in the duration of drug intake before onset, the levels of IgG, IgA and IgM, the numbers of circulating white blood cell, lymphocyte, CD3+ T cell and CD8+ T cells, the serum levels of interferon-γ, and the titres of anti-herpes simplex virus IgG at onset. Conclusions. The difference in the pattern of immune responses shaped in part by previous and underlying viral infections at the time of drug exposure could cause a marked deviation in the pathological phenotype of severe drug eruptions. Elucidating these host factors may provide a basis for therapeutic approaches in patients with severe drug reactions.     

Hypersensitivity syndrome due to trichloroethylene exposure: a severe generalized skin reaction resembling drug-induced hypersensitivity syndrome

The number of patients suffering from trichloroethylene (TCE)-related severe skin disorders with liver dysfunction has been increasing in developing countries in Asia, especially since the mid-1990s. In Japan, five cases of this disease have been reported, but none since the 1990s. However, two additional cases were recently observed in Tokyo. The published work and our investigation indicated that oxidative metabolites of TCE, which might include trichloroacetylated-protein adducts, could induce a generalized skin eruption. Furthermore, human leukocyte antigen (HLA)-B*1301 and HLA-B*44 were identified as markers of individual susceptibility to TCE-induced hypersensitivity syndrome (HS). Moreover, polymorphism of aldehyde dehydrogenase (ALDH), the major enzyme in TCE metabolism, appeared to be associated with TCE-induced HS. Interestingly, this disorder is quite similar to drug-induced hypersensitivity syndrome (DIHS), also referred to as drug rash with eosinophilia and systemic symptoms (DRESS), from the perspective of the onset of the reaction after exposure to TCE/drugs, clinical manifestations, blood examination and period of virus reactivation. This article reviews the similarity between TCE-related HS and DIHS/DRESS.     

Acute generalized exanthematous pustulosis: analysis of cases managed in a tertiary hospital in Singapore

Acute generalized exanthematous pustulosis We reviewed eight cases of acute generalized exanthematous pustulosis managed in a tertiary hospital in Singapore. Background Acute generalized exanthematous pustulosis (AGEP) is a pustular reaction characterized by a sudden eruption of widespread nonfollicular sterile pustules associated with systemic symptoms. AGEP is primarily believed to be an adverse reaction to drugs. Outside of Europe, few reports exist on the clinical presentation of AGEP. Methods  A retrospective review of patients who presented with AGEP to a Singapore tertiary hospital was performed. Results Eight patients were diagnosed with AGEP in 2006–2007. All patients presented with a macular, maculopapular eruption prior to the onset of pustules. AGEP was characterized by nonfollicular, pinpoint pustules, which were generalized and accentuated in the flexural areas in seven of the patients. The remaining patient had erythematous patches, and scattered plaques studded with pustules. Other less common features included oral/genital mucositis, blisters and erosions. The mean duration from the cessation of medications to defervescence, resolution of pustules and normalization of leukocytosis was 5, 6, and 7 d, respectively. Despite the resolution of pustules, two patients had protracted clinical courses with evolution to generalized exfoliative dermatitis and Drug rash, eosinophilia, and systemic symptoms (DRESS), respectively. The implicated medications included antibiotics in six patients, morphine and phenytoin in one patient each. Conclusions Acute generalized exanthematous pustulosis is generally described as benign and self‐limiting. However, in certain patients, the clinical course is prolonged and may exhibit features that overlap with other forms of cutaneous adverse drug reactions such as toxic epidermal necrolysis and DRESS.