Metronidazole-related Stevens-Johnson syndrome: a case report and literature review

To analyze the clinical characteristics and management strategies of metronidazole-associated Stevens-Johnson syndrome (SJS), and to provide a clinical basis for medication safety during the oral perioperative period.

The study adhered to the tenets of the Declaration of Helsinki and was approved by the Ethics Committee of Stomatological Hospital of Xi'an Jiaotong University. A retrospective analysis was conducted on a case of SJS following mandibular impacted tooth extraction, for which the patient had taken metronidazole. Additionally, a literature review was performed by searching databases including China National Knowledge Infrastructure, Wanfang, PubMed, and Web of Science to identify reported cases of metronidazole-associated SJS. Demographic features, medication regimens, latency periods, clinical signs, interventions, and prognosis were analyzed.

The patient presented with lip swelling, extensive erosion and ulceration of the oral mucosa, and severe odynophagia. Scattered erythematous macules and bullae were observed on the trunk and extremities, with a positive Nikolsky sign. Additionally, there was erosion of the perineal skin and glans penis mucosa, along with skin desquamation of the scrotum. The patient with SJS was managed in the hospital by discontinuing metronidazole and administering sequential treatments, including glucocorticoids, immunomodulators, intravenous immunoglobulin, and plasma exchange. The condition gradually improved; after a 14-month follow-up, only mild dry eye remained, with no significant scarring of the skin or mucosa. However, delayed recognition of early warning signs resulted in delayed drug withdrawal and intervention. The literature review identified 6 additional cases (3 males, 3 females) with a median age of 45.5 years (range 31–61). Indications for metronidazole included postoperative sepsis prophylaxis after duodenal ulcer perforation repair, digestive system infections, mucosal diseases, pelvic inflammatory disease, septic cellulitis with pneumonia, and gingivitis. Administration routes comprised oral (n = 2), intravenous (n = 3), and topical (n = 1). The latency period from drug administration to onset ranged from 0.25 to 7 days (median 4 days). All of the cases presented with oral mucosal erosion, and a positive Nikolsky’s sign was noted for five patients. Discontinuation of the causative drug was the cornerstone of treatment, supplemented by immunomodulatory therapy, symptomatic support, and multidisciplinary collaboration. Prognoses varied significantly: among the four patients treated with“ drug withdrawal + glucocorticoids + supportive care, ” three recovered fully and one improved; among the two patients receiving“ drug withdrawal + simple supportive care, ” one recovered and one died.

Although metronidazole-associated SJS is rare, it progresses rapidly and frequently involves oral mucosal damage, typically occurring within one week of administering the medication. Early drug withdrawal and prompt initiation of glucocorticoid therapy can improve prognosis. During the oral perioperative period, strict adherence to metronidazole indications, enhanced monitoring for early warning symptoms, and the establishment of a multidisciplinary collaborative diagnosis and treatment model are essential to minimize the risk of severe adverse drug reactions.