Recognizing rare rashes: A case of acute generalized exanthematous pustulosis

ABSTRACT

Acute generalized exanthematous pustulosis (AGEP) is a rare, pustular rash that occurs most commonly after exposure to a medication (typically antibiotics or diltiazem). This case describes a patient who developed a widespread pustular eruption shortly after beginning empiric antibiotics for community-acquired pneumonia. Diagnosis of AGEP was difficult in this scenario due to the patient's pulmonary infection and atypical skin biopsy results. However, after AGEP was correctly identified, the offending agents were discontinued and the patient had subsequent resolution of her symptoms.

Generalized Pustular Psoriasis, Acute Generalized Exanthematous Pustulosis, and Other Pustular Reactions: A Clinical Review

Generalized pustular rashes have various etiologies and can be challenging to diagnose and manage at first presentation. The authors provide an in-depth analysis of common pustular skin eruptions including generalized pustular psoriasis (GPP) and acute generalized exanthematous pustulosis, focusing on their pathophysiology, triggers, clinical presentation, diagnostic challenges, and management strategies. The article also highlights recent advances in genetic research and biologic therapies for GPP and the future directions in personalized medicine and prevention strategies.

Cutaneous adverse drug reactions

Cutaneous adverse drug reactions (ADRs) represent a heterogeneous field including various clinical patterns without specific features suggesting drug causality. Maculopapular exanthema and urticaria are the most common types of cutaneous ADR. Serious cutaneous ADRs, which may cause permanent sequelae or have fatal outcome, may represent 2% of all cutaneous ADR and must be quickly identified to guide their management. These serious reactions include bullous manifestations (epidermal necrolysis i.e. Stevens-Johnson syndrome and toxic epidermal necrolysis), drug reaction with eosinophilia and systemic symptoms (DRESS) and acute generalized exanthematous pustulosis (AGEP). Some risk factors for developing cutaneous ADRs have been identified, including immunosuppression, autoimmunity or genetic variants. All drugs can cause cutaneous ADRs, the most commonly implicated being antibiotics (especially aminopenicillins and sulfonamides), anticonvulsants, allopurinol, antineoplastic drugs, non-steroidal anti-inflammatory drugs and iodinated contrast media. Pathophysiology is related to immediate or delayed "idiosyncratic" immunologic mechanisms, i.e., usually not related to dose, and pharmacologic/toxic mechanisms, commonly dose-dependent and/or time-dependent. If an immuno-allergic mechanism is suspected, allergological explorations (including epicutaneous patch testing and/or intradermal test) are often possible to clarify drug causality, however these have a variable sensitivity according to the drug and to the ADR type. No in vivo or in vitro test can consistently confirm the drug causality. To determine the origin of a rash, a logical approach based on clinical characteristics, chronologic factors and elimination of differential diagnosis (especially infectious etiologies) is required, completed with a literature search. Reporting to pharmacovigilance system is therefore essential both to analyze drug causality at individual level, and to contribute to knowledge of the drug at population level, especially for serious cutaneous ADRs or in cases involving newly marketed drugs.

Acquired cutis laxa secondary to acute generalized exanthematous pustulosis: A case report and mini-review of literature

Cutis laxa presents as loose redundant skin folds and loss of dermal elastic tissue. Acquired cutis laxa (ACL) is characterized by later onset. It has been reported in association with various kinds of neutrophilic dermatoses, drugs, metabolic disorders, and autoimmune disorders. Acute generalized exanthematous pustulosis (AGEP) is usually classified as a severe cutaneous adverse reaction characterized by T cell-mediated neutrophilic inflammation. We previously reported a mild case of AGEP caused by gemcitabine in a 76-year-old man. Here, we report a case of ACL secondary to AGEP in this patient. He developed AGEP 8 days after gemcitabine administration. Four weeks after beginning chemotherapy, his skin had become atrophic, loose, and darkly pigmented in areas previously affected by AGEP. Histopathological examination revealed edema and perivascular lymphocytic infiltration but no neutrophilic infiltration in the upper dermis. Elastica van Gieson staining showed that the elastic fibers in all layers of the dermis were sparse and shortened. Electron microscopy showed elevated numbers of fibroblasts and altered elastic fibers with irregular surfaces. Finally, he was diagnosed with ACL secondary to AGEP. He was treated with topical corticosteroids and oral antihistamines. Skin atrophy decreased over 3 months. We summarize 36 cases (including our case) with ACL secondary to neutrophilic dermatosis. We discuss these clinical manifestations, causative neutrophilic disorders, treatments, and outcomes. The mean age of patients was 3.5 years. Five patients had an aortic lesion as systemic involvement. The most common causative neutrophilic disorders were Sweet syndrome (24 cases), followed by urticaria-like neutrophilic dermatosis (11 cases). There were no cases of AGEP except for our case. Although treatment for ACL secondary to neutrophilic dermatosis, such as dapsone, oral prednisolone, adalimumab, and plastic surgery were reported, ACL is generally refractory and irreversible. Our patient was considered reversibly cured due to the absence of continuous neutrophil-mediated elastolysis.

Medication Associations With Severe Cutaneous Adverse Reactions: A Case/Non-Case Analysis Using the FDA Adverse Event Reporting System

BACKGROUND

Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS), and acute generalized exanthematous pustulosis (AGEP) are potentially life-threatening severe cutaneous adverse reactions (SCARs). Although the classical causal agents of SCARs (antibiotics, anticonvulsants, nonsteroidal anti-inflammatory drugs, and allopurinol) are well characterized, there has been little update to this list to account for newly marketed medications.

OBJECTIVE

To provide an updated and stratified list of medications with significant reporting odds ratios (RORs) of SCARs.

METHODS

A case/non-case analysis using the United States FDA Adverse Event Reporting System was performed.

RESULTS

As expected, the prototypical medication classes made up the majority of reported cases of SJS, TEN, AGEP, and DRESS (77%, 64%, 75%, and 72%, respectively). In addition, several infrequently or previously undescribed classes/medications implicated in SCARs were identified to have significant ROR signals, including acetylcysteine, anticoagulants, diuretics, immunotherapies, proton pump inhibitors, antivirals, and antifungals. Among these reported for SJS were acetylcysteine (ROR: 64.38) and fluconazole (ROR: 17.13). For TEN, we identified furosemide (ROR: 26.32), spironolactone (ROR: 14.45), fluconazole (ROR: 30.21), amphotericin B (39.06), and acetylcysteine (ROR: 93.12). For AGEP, we identified acyclovir (ROR: 61.72), valacyclovir (ROR: 30.76), and enoxaparin (ROR: 27.37). For DRESS, we identified vemurafenib (ROR: 17.35), acyclovir (ROR: 30.63), abacavir (ROR: 26.62), raltegravir (ROR: 23.27), and valacyclovir (ROR: 21.77) to have strong reporting odds.

CONCLUSION

Our analysis provides an updated tool for physicians to reference when identifying suspected SCARs and a basis for future studies to investigate atypical medication causality.

Acute generalized exanthematous pustulosis caused by hydroxychloroquine in a patient with rheumatoid arthritis and CARD14 mutation: Case report

RATIONALE

Acute generalized exanthematous pustulosis (AGEP) is a serious adverse skin reaction characterized by the rapid appearance of densely distributed, small, sterile pustules with erythema. However, its pathogenesis is not fully understood. Hydroxychloroquine is widely used for the treatment of autoimmune diseases. Some patients presenting with AGEP have IL36RN and CARD14 gene mutations. Our report describes a patient with rheumatoid arthritis and AGEP associated with hydroxychloroquine and a newly discovered CARD14 gene mutation.

PATIENT CONCERNS

A 28-year-old woman with rheumatoid arthritis, treated with leflunomide therapy without marked relief of joint pain, developed multiple rashes with pruritis covering the body 5 days after switching to hydroxychloroquine treatment.

DIAGNOSES

Based on the patient's history, symptoms, and histopathological findings, AGEP was diagnosed.

INTERVENTIONS

Whole-exome sequencing and Sanger validation revealed no mutations in the IL36RN gene; however, a CARD14 gene mutation was present. The patient was treated using ketotifen fumarate tablets, dexamethasone sodium phosphate, calcium gluconate injection, methylprednisolone injection, vitamins C and B12, hydrocortisone butyrate cream, Reed acne cream, potassium chloride tablets, and pantoprazole enteric-coated capsules.

OUTCOMES

The rash improved after 15 days.

LESSONS SUBSECTIONS

There has been little basic research on AGEP-related genetics, and the CARD14 mutation may underlie several pustular rashes, including AGEP and generalized pustular psoriasis. Follow-up studies and further accumulation of patient data are required.

Concurrent acute generalized exanthematous pustulosis in siblings

Acute generalized exanthematous pustulosis (AGEP) is a rare severe cutaneous adverse reaction triggered in most cases by drugs. It is characterized by abrupt onset and rapid evolution of fields of sterile pustules on an erythematous background. The role of genetic predisposition in this reactive disorder is being explored. We report the simultaneous occurrence of AGEP in two siblings after being exposed to the same drug.

Acute generalized exanthematous pustulosis associated with clindamycin in a patient with Hailey-Hailey disease

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

Acute generalized exanthematous pustulosis complicated by cutaneous small vessel vasculitis: A case report and literature review

Acute generalized exanthematous pustulosis (AGEP) is a rare skin eruption characterized by widespread erythematous lesions covered with numerous pustules. Leukocytoclastic vasculitis is now considered an uncommon but possible histopathological feature within the clinical and pathological spectrum of AGEP. Our report describes a rare case of AGEP overlapping with cutaneous small vessel vasculitis, a condition that has only been reported once in the literature.

Drug triggered pruritus, rash, papules, and blisters - is AGEP a clash of an altered sphingolipid-metabolism and lysosomotropism of drugs accumulating in the skin?

Rash, photosensitivity, erythema multiforme, and the acute generalized exanthematous pustulosis (AGEP) are relatively uncommon adverse reactions of drugs. To date, the etiology is not well understood and individual susceptibility still remains unknown. Amiodarone, chlorpromazine, amitriptyline, and trimipramine are classified lysosomotropic as well as photosensitizing, however, they fail to trigger rash and pruritic papules in all individuals. Lysosomotropism is a common charcteristic of various drugs, but independent of individuals. There is evidence that the individual ability to respond to external oxidative stress is crosslinked with the elongation of long-chain fatty acids to very long-chain fatty acids by ELOVLs. ELOVL6 and ELOVL7 are sensitive to ROS induced depletion of cellular NADPH and insufficient regeneration via the pentose phosphate pathway and mitochondrial fatty acid oxidation. Deficiency of NADPH in presence of lysosomotropic drugs promotes the synthesis of C16-ceramide in lysosomes and may contribute to emerging pruritic papules of AGEP. However, independently from a lysosomomotropic drug, severe depletion of ATP and NAD(P)H, e.g., by UV radiation or a potent photosensitizer can trigger likewise the collapse of the lysosomal transmembrane proton gradient resulting in lysosomal C16-ceramide synthesis and pruritic papules. This kind of papules are equally present in polymorphous light eruption (PMLE/PLE) and acne aestivalis (Mallorca acne). The suggested model of a compartmentalized ceramide metabolism provides a more sophisticated explanation of cutaneous drug adverse effects and the individual sensitivity to UV radiation. Parameters such as pKa and ClogP of the triggering drug, cutaneous fatty acid profile, and ceramide profile enables new concepts in risk assessment and scoring of AGEP as well as prophylaxis outcome.

Pustular Psoriasis and Acute Generalized Exanthematous Pustulosis

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

Recognition and Management of Severe Cutaneous Adverse Drug Reactions (Including Drug Reaction with Eosinophilia and Systemic Symptoms, Stevens-Johnson Syndrome, and Toxic Epidermal Necrolysis)

Severe cutaneous adverse reactions to medications (SCARs) include drug reaction with eosinophilia and systemic symptoms, Stevens-Johnson syndrome, toxic epidermal necrolysis, and acute generalized exanthematous pustulosis. They are all non-immunoglobulin E mediated hypersensitivity reaction patterns, distinguished from simple cutaneous drug eruptions by immunologic pathogenesis and internal organ involvement. Herein the clinical features, diagnostic workup, and management considerations are presented for each of these major SCARs.

Widespread pustular eruption following probiotic use

A 26-year-old woman with Crohn disease and palmoplantar psoriasis on ustekinumab presented with a diffuse and intensely pruritic rash with a few pin-point pustules within days after initiation of an over-the-counter Align brand probiotic. Biopsy revealed psoriasiform and spongiotic dermatitis with spongiform subcorneal pustules and scattered eosinophils, consistent with acute generalized exanthematous pustulosis. Our case highlights a unique presentation of acute generalized exanthematous pustulosis following probiotic exposure with fewer than usual pustular lesions. IL23 suppression by ustekinumab may have contributed to the patient's reduced pustular presentation.

Fluconazole-induced acute generalized exanthematous pustulosis

Acute generalized exanthematous pustulosis (AGEP) is a rare severe cutaneous adverse reaction usually caused by drugs. The annual incidence is one to five cases per million. It is characterized by an acute febrile episode, accompanied by numerous small primarily non-follicular, sterile pustules arising within large areas of edematous erythema. There have been several case reports to date of AGEP following exposure to antifungals. Terbinafine is most commonly implicated in AGEP. We report a case of 7-year-old boy who developed AGEP shortly after commencing oral fluconazole for Tinea capitis. To our knowledge, this is the fourth reported case of AGEP due to fluconazole.

Clindamycin-induced acute generalized exanthematous pustulosis: A case report

RATIONALE

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

PATIENT CONCERNS

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

DIAGNOSIS

Clindamycin-induced AGEP.

INTERVENTIONS

We discontinued clindamycin treatment and prescribed systemic corticosteroids.

OUTCOMES

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

LESSONS

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

Clinicopathologic retrospective analysis of annular pustular psoriasis

Annular pustular psoriasis (APP) is a rare form of pustular psoriasis with a chronic relapsing course and a good prognosis. The clinical picture is characterized by erythematous lesions, usually polycyclic, with the presence of small, sterile pustules on the circumference of the lesions and fine peeling. We present two cases of APP with diagnostic problems: a 65-year-old woman that suffered from intermittent APP with remission and exacerbation for many years, and an 83-year-old man with lesions that developed after atenolol treatment. In both cases, the patients were thought to have drug provocation, and therefore acute generalized exanthematous pustulosis (AGEP) was diagnosed. Only a thorough analysis of the course of the disease and histopathological examination allowed correct diagnosis. The clinical picture of APP is similar to AGEP, generalized pustular psoriasis (GPP), also known as von Zumbusch pustular psoriasis, and subcorneal pustular disease, and it requires accurate differential diagnosis.

Clinical characteristics, culprit drugs and outcome of patients with Acute Generalised Exanthematous Pustulosis seen in Hospital Sultanah Aminah, Johor Bahru

BACKGROUND

Acute generalised exanthematous pustulosis (AGEP) is a rare, cutaneous reaction characterised by sudden onset of numerous, non-follicular, sterile pustules on oedematous erythematous skin, accompanied by fever and neutrophilia. AGEP is predominantly drug-induced. Skin lesions appear rapidly within 1-3 days of drug exposure and upon drug withdrawal, resolve rapidly within 15 days.

OBJECTIVE

To determine the clinical characteristics, culprit drugs and outcome of patients with AGEP.

METHODS

A retrospective note review of all AGEP patients seen from 2001-2015.

RESULTS

Among 21 AGEP patients, 76% were Malays, 9.5% Chinese, 9.5% Indians, and 5% Iban. Sixteen were females and 5 were males. Median age of patients was 40 years (IQR: 26). The main culprit drug was amoxicillin (10 cases), followed by cloxacillin (three cases), phenytoin (two cases) and one case each of carbamazepine, sulphasalazine, allopurinol, cephalexin, ceftriaxone, celecoxib and herbal product. The median time from drug initiation to onset of AGEP was 3 days (IQR: 5.5). Fever was documented in 52.4 %, mucosal involvement 9.5%, purpura 4.7% and blisters 4.7%. Neutrophilia was observed in 63.6% of patients and eosinophilia in 28.5%. While most patients required admission (67%), all achieved complete recovery within 15 days without any sequela.

CONCLUSIONS

AGEP predominantly affects Malay females in this study. The most common culprit drug was amoxicillin. Our patients exhibited the classic clinical manifestations of AGEP and confirmed the generally benign nature of this reaction upon drug withdrawal. Although the overall prognosis is good, prompt diagnosis of AGEP is important because drug withdrawal is the mainstay therapy.

Severe cutaneous adverse reactions to drugs

During the past decade, major advances have been made in the accurate diagnosis of severe cutaneous adverse reactions (SCARs) to drugs, management of their manifestations, and identification of their pathogenetic mechanisms and at-risk populations. Early recognition and diagnosis of SCARs are key in the identification of culprit drugs. SCARS are potentially life threatening, and associated with various clinical patterns and morbidity during the acute stage of Stevens-Johnson syndrome and toxic epidermal necrolysis, drug reactions with eosinophilia and systemic symptoms, and acute generalised exanthematous pustulosis. Early drug withdrawal is mandatory in all SCARs. Physicians' knowledge is essential to the improvement of diagnosis and management, and in the limitation and prevention of long-term sequelae. This Seminar provides the tools to help physicians in their clinical approach and investigations of SCARs.

A Case of Amoxicillin-Induced Acute Generalized Exanthematous Pustulosis Presenting as Septic Shock

This case report demonstrates the challenges of diagnosing and managing acute generalized exanthematous pustulosis (AGEP) presenting as septic shock. The disseminated, erythematous, pustular rash is a common feature. However, extensive organ involvement and life-threatening hypotension are unusual. The constellation of signs has not previously been documented following amoxicillin therapy. Toxic epidermal necrolysis (TEN) and toxic shock syndrome (TSS) were considered in addition to AGEP because of the systemic presentation. AGEP was diagnosed following histopathology (TEN was ruled out based on limited necrotic keratinocytes and lack of epidermal necrosis) and a negative antistreptolysin O titer (eliminated TSS). Antibiotic therapy for septic shock was provided before the diagnosis was confirmed as AGEP. Upon confirmation of the AGEP diagnosis, antibiotics were discontinued and a 5-day course of oral prednisone (40 mg/d) was initiated in addition to topical half-strength (0.05%) betamethasone valerate. The patient rapidly improved and was discharged. Outpatient patch testing confirmed amoxicillin as the culprit drug. In conclusion, it is critical to realize that AGEP cannot be ruled out with a septic shock presentation. Recent drug history is critical in recognizing an adverse drug reaction, and patch testing is useful for determining the culpable drug when the diagnosis is AGEP.

First report of mesalamine (5-aminosalicylic acid) as the causative agent in a case of acute generalized exanthamous pustulosis

Acute generalized exanthamous pustulosis (AGEP)is a rare eruption of non-follicular sterile pustuleson a diffuse background of erythema and edema,commonly associated with fever and leukocytosis.Antibiotics are implicated in most cases; however,other drugs have been reported to cause AGEP. Wereport a case of a 73-year-old man with a historyof ulcerative colitis who presented with a diffusepustular rash, renal failure, elevated liver functiontests, and leukocytosis with neutrophilia. A week priorto admission, the patient was started on mesalamineto treat colitis. Upon admission, a workup includinga skin biopsy was performed and was consistentwith AGEP. Mesalamine was discontinued, and thepatient's skin eruption, renal function, liver functiontests, and leukocytosis subsequently improved.Mesalamine has an unknown mechanism of action.However, it is thought to be an anti-inflammatoryagent that blocks the production of leukotrienesand prostaglandins and is an immunosuppressantthat increases the release of adenosine, whichinterferes with leukocyte function. The decrease inprostaglandin synthesis or deregulation of leukocytefunction caused by mesalamine may be the etiologyin this case. Discontinuation of the offending agentleads to resolution of AGEP, as it did in this patient.

Clindamycin-induced acute generalised exanthematous pustulosis: five cases and a review of the literature

Acute generalised exanthematous pustulosis (AGEP) is a rare but serious cutaneous adverse drug reaction, often related to antibiotics such as beta-lactams or macrolides. However, it is rarely associated with clindamycin which belongs to the lincosamide antibiotics. The Netherlands Pharmacovigilance Centre Lareb received five reports of AGEP associated with the use of clindamycin. We present these five cases and provide support for this association from the Lareb database, the database of the WHO Collaborating Centre for International Drug Monitoring (Vigibase™), the database of the European Medicine Agency (Eudravigilance), and from a mini review of the literature.

Severe drug-induced skin reactions: clinical features, diagnosis, etiology, and therapy

Drugs can induce severe skin reactions that differ in clinical presentation, prognosis, and therapy. The spectrum of these reactions not only includes bullous reactions such as Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and generalized bullous fixed drug eruption (GBFDE) but also acute generalized exanthematous pustulosis (AGEP) and drug reaction with eosinophilia and systemic symptoms (DRESS). If AGEP or DRESS is suspected, the diagnosis should be confirmed by thorough clinical examination, a skin biopsy, and specific laboratory tests. Crucial for the patient's prognosis, the causative agent should be rapidly identified and discontinued. It is therefore important to know the most frequent triggers of severe drug reactions, some of which may induce various reaction patterns. Depending on the clinical diagnosis, symptomatic and adequate supportive therapy, as well as systemic immunomodulatory treatments are used. The prognosis in SJS/TEN is often poor and depends on the patient's age and underlying conditions as well as the extent of skin detachment. The prognosis of GBFDE is somewhat better, but recurrences may lead to more severe disease manifestations. In DRESS, protracted and recurrent courses have been described, whereas AGEP usually resolves without problems.

Prolonged pustular eruption from hydroxychloroquine: an unusual case of acute generalized exanthematous pustulosis

Acute generalized exanthematous pustulosis (AGEP) is a rare cutaneous eruption that often is a reaction to medications, most commonly antibiotics. Clinically, AGEP closely mimics pustular psoriasis and also is similar to subcorneal pustular dermatosis and IgA pemphigus. For clinicians, it is important to differentiate AGEP from pustular psoriasis. Acute generalized exanthematous pustulosis will have an acute drug association. Few cases have been known to be caused by hydroxychloroquine (HCQ). Proper therapeutic management of AGEP includes withdrawal of the offending agent, and resolution typically occurs within 15 days. We report a case of AGEP after HCQ administration that did not follow the usual course of resolution after medication cessation. The patient continued to experience cutaneous eruptions that waxed and waned for 81 days. Hydroxychloroquine has a particularly long half-life and is a known cause of AGEP; therefore, it is possible that HCQ-induced AGEP may not follow the typical rapid recovery time.

Severe adverse drug reactions

Severe cutaneous adverse reactions (SCARs) can present in a multitude of ways including Stevens-Johnson syndrome, toxic epidermal necrolysis, drug reaction with eosinophilia and systemic symptoms, and acute generalised exanthematous pustulosis. While the prognosis and therapy for these conditions may vary, it is crucial that the culprit drug is identified and withheld early as this can influence patient outcome. Mainstay of management is by supportive therapy. In all SCARs, long-term sequelae which may not be apparent initially can be debilitating and cause lasting impact on the quality of life of survivors.

Acute generalised exanthematous pustulosis (AGEP)-a potential pitfall for the acute physician

Acute generalised exanthematous pustulosis is a rare drug-induced dermatosis with an incidence of 1-5 cases per million cases per year, characterised by the appearance of hundreds of sterile pustules over erythematous and oedematous skin. Fever and neutrophilia are usually present. It has a rapid course and usually resolves following discontinuation of the precipitating drug or as a result of topical corticosteroid treatment. A patient with AGEP, who presented with generalized pustulosis lesions after the use of Flucloxacillin for cellulitis is described, along with the management and differential diagnosis of this condition.

[Severe erythema and pustules after antibiotic use: acute generalised exanthematous pustulosis]

BACKGROUND

Acute generalised exanthematous pustulosis (AGEP) is a rare and self-limiting pustular cutaneous reaction to a drug or infection.

CASE DESCRIPTION

A 62-year-old male presented to the Emergency Department with fever, erythema and pustules on both thighs. The initial blood analysis showed increased inflammatory parameters. The patient was admitted to the Dermatology Department with suspected AGEP. All medication was stopped. The diagnosis was confirmed histologically. During hospitalisation, the cutaneous reaction spread over 30% of the skin surface. Seven days after onset, the skin disorder regressed and the patient was discharged after 16 days. Use of amoxicillin/clavulanic acid was very likely the triggering factor for the development of AGEP.

CONCLUSION

AGEP, although self-limiting, can have a fulminant course, requiring admission to a burns centre. It is imperative that rechallenge with the triggering drug is avoided.