Allopurinol-induced toxic epidermal necrolysis featuring almost 60% skin detachment

Allopurinol: Clinical Considerations in the Development and Treatment of Stevens-Johnson Syndrome, Toxic Epidermal Necrolysis, and Other Associated Drug Reactions

Allopurinol lowers urate production through the inhibition of xanthine oxidase. It is oxidatively hydroxylated to oxypurinol and is the most prescribed medication for gout treatment. Although it has a beneficial effect in the treatment of this common disease, like many medications, it is also known for having numerous adverse effects. Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), diseases that exist on a spectrum, are two of the most dangerous adverse effects associated with allopurinol use. These immune-mediated disease processes involve almost every organ system. They are essential to recognize as early as possible, as they could potentially be deadly, requiring cessation of the medication with initial signs of rash or other early manifestations of SJS/TEN. One major consideration in the increased risk of allopurinol-mediated or modulated SJS/TEN is the need to have a lower dose in the setting of renal disease. The purpose of this review is not only to examine the involvement of allopurinol in SJS/TEN but also to provide detailed information about the drug, allopurinol, and general features and characteristics of SJS/TEN and other associated drug reactions.

Allopurinol-Induced Toxic Epidermal Necrolysis

Toxic epidermal necrolysis (TEN) is a rare and life-threatening cutaneous disease, frequently triggered by drugs. Allopurinol is one of the most frequent drugs associated with TEN, which implies detachment of a significant amount of the body surface area (BSA) and has a high morbidity and mortality associated with it. We present the case of a 68-year-old female with a recent diagnosis of hyperuricemia who started treatment with allopurinol. A week later, she presented to the emergency department with an extensive maculopapular exanthema with blisters and skin detachment. After the exclusion of other etiologies, the diagnosis of allopurinol-induced TEN was made, with 35% of BSA involvement. Due to the severity of the clinical condition, she was admitted to intensive care and treated with corticoids that had no response. So, she was started on immunoglobulins and transferred to a burn unit. She developed sepsis with multiorgan failure and required supportive treatment. She was discharged after a month, and physical rehabilitation was needed. This clinical case highlights the severity of allopurinol hypersensitivity that may happen and the importance of an accurate diagnosis and treatment for this rare disease.

Allopurinol-Induced Stevens-Johnson Syndrome (SJS)

Allopurinol is a commonly used medication that lowers uric acid production which is essential for gout treatment and prevention. Although many patients tolerate allopurinol therapy without severe complications; Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) are life-threatening delayed hypersensitivity reactions that have been reported especially among Asian and African American patients. We describe a case of allopurinol-induced SJS in a 95-year-old Asian female. The patient started allopurinol 13 days prior to presenting to the emergency room (ER). On day 10 of therapy, the patient developed a diffuse erythematous desquamating rash which prompted her to visit the ER after 3 days from the rash onset. This case report describes a rare fatal hypersensitivity reaction that requires rapid identification and treatment in a multi-disciplinary setting.

Toxic Epidermal Necrolysis Caused by Allopurinol: A Serious but Still Underestimated Adverse Reaction

Patient: Female, 75-year-old

Final Diagnosis: Toxic epidermal necrolysis

Symptoms: Exanthema • rash • shivers • weakness

Medication: —

Clinical Procedure: Analgesia • ciclosporine • corticosteroids • topical and systemic treatment

Specialty: Critical Care Medicine • Dermatology

Case Report: Positive Outcome of a Suspected Drug-Associated (Immune Mediated) Reaction in a 4-Year-Old Male French Bulldog

Toxic epidermal necrolysis (TEN) is a rare and severe life-threatening syndrome characterized by apoptosis of keratinocytes resulting in devitalization of the epidermis affecting more than 30% of skin surface. In humans and animals, this condition is mostly triggered by drugs. Identification of the putative agent and its withdrawal are crucial to successful management of a patient with TEN. In this case study, we report the clinical features, histopathological findings and management of a dog with TEN. A 4-year-old intact male French bulldog presented with acute onset of severe lethargy and cutaneous ulcerations on the footpads, scrotum, and hind limbs associated with marked pain. A Stevens-Johnson syndrome/TEN was suspected and drugs, especially beta-lactams, were withdrawn. Histopathology confirmed the diagnosis of epidermal necrosis. Advanced supportive therapy, pain management and skin care led to rapid remission. Early identification and removal of the suspected medication was crucial to improving TEN prognosis in this dog. Antibiotics (penicillin, ampicillin, cephalexin, and sulfonamides) are frequently involved in adverse cutaneous reactions in dogs. Ideal treatment remains elusive is humans and dogs and this disease has a poor prognosis. Supportive care combined with pain management and treatment of the cutaneous ulcerations is essential.