Acute generalized exanthematous pustulosis simulating toxic epidermal necrolysis: case presentation and literature review

Abstract

Background: Acute generalized exanthematous pustulosis (AGEP) and toxic epidermal necrolysis (TEN) are severe cutaneous adverse reactions. These rare conditions differ in clinical presentation, pathological features, treatment and prognosis, but overlap has been described implying a challenging clinical management. Case presentation: We describe a case of overlap between TEN and AGEP probably secondary to beta-lactams in a 77-year-old patient treated for a complicated cholangitis. We review the diagnosis and the management of these two conditions. The diagnosis of TEN was suggested by the initial clinical presentation with severe hemodynamic instability, skin detachment, positive Nikolsky sign and mucosal involvement. However, the skin biopsy as well as the rapid improvement of the skin lesions were discriminative for AGEP. This indicated an overlap presentation. Unfortunately, the patient refused allergy investigations in order to find the culprit drug. Medical photographs, proper physical examination and histopathological results are integrated. Conclusion: Despite clinical features indicating a diagnosis of TEN, histopathology was conclusive for AGEP thus indicating a possible clinical-pathological overlap between the two conditions, a scarcely described situation in the medical literature. To our knowledge, this is one of the few cases that portrays a TEN-AGEP overlap probably secondary to Piperacillin Tazobactam. Understanding the immunological implications of these conditions can help us better distinguish and manage these severe reactions.

Generalized pustular figurate erythema: A newly delineated severe cutaneous drug reaction linked with hydroxychloroquine

“…There is another rare acute severe generalized disorder, one usually characterized as AGEP, but with an onset of 2 to 3 weeks (range 4‐27 days) rather 1 day after initial drug exposure, typically due to hydroxychloroquine, more severe, more difficult to treat, with a longer duration, and recognized as likely having a different pathogenic mechanism from the usual type of AGEP 10 . This perplexing disorder has been described as atypical AGEP, 11,12 recalcitrant AGEP, 13,14 pustular DRESS syndrome, 15 AGEP/SJS overlap, 16 AGEP/TEN overlap, 17,18 and Sweet's syndrome following hydroxychloroquine 19‐21 . We delineate and highlight it as generalized pustular figurate erythema (GPFE).…”

“…Clinical examination reveals an abrupt onset of a pruritic eruption representing a severe cutaneous drug reaction with fever and neutrophilic leukocytosis 11‐21 . GPFE may be first evident as erythematous papules and plaques on the face with facial edema and widespread urticarial or edematous plaques scattered over the entire body, with development of nonfollicular pustules atop what evolve into erythematous and sometimes atypical targetoid erythema multiforme‐like plaques converging into annular and arcuate patterns prominent on the trunk and extremities (Figure 1).…”

“…Treatments have been varied 11‐21,24‐26 . The first line therapy is topical and systemic steroids, which may be followed by cyclosporine if GPFE is not responsive 13,14,21 .…”

Severe acute generalized exanthematous pustulosis with toxic epidermal necrolysis-like desquamation: A case series of 8 patients

“… 4 TEN-like AGEP has been reported in the literature and its differentiation from actual TEN is critical to avoiding overtreatment. 3 …”

“… 2 Although classic AGEP differs from TEN by clinical appearance and histopathologic findings, cases with overlapping features have rarely been reported in the literature. 3 Importantly, distinguishing severe AGEP from TEN is essential due to differences in prognosis and management. We present a case series of AGEP with TEN-like desquamation and highlight important clues in identifying severe and atypical cases of AGEP.…”