P07 | Adverse events of antibiotics: a vancomycin-induced linear IgA bullous dermatosis

Premises: Linear IgA bullous dermatosis is an autoimmune blistering skin disorder either idiopathic or drug-induced, with vancomycin being the most common. We present a case of a new-onset blistering rash during treatment with vancomycin and piperacillin-tazobactam.Description of the Case report: A 76-year-old woman, known for arterial hypertension is admitted to our institution, 1 week after osteosynthesis of right femur: she had fever, hypotension, oliguria and significant increase in inflammatory markers, radiological finding of pneumonia and haemocultures positive for Staphylococcus hominis; she was started on piperacillin/tazobactam and vancomycin. On the 12th day of admission, the patient developed multiple, confluent tense vesicles on the upper back, the upper limbs and oral mucosa. She had no known history of drug allergy, her vitals were normal, and she had no complaint of other symptoms. Laboratory values were unremarkable, even a base autoimmune panel; a total body CT scan and an echocardiogram were normal. We performed skin biopsy which showed a linear IgA dermatosis. The patient was treated with withdrawal of vancomycin, local and systemic corticosteroid therapy; the clinical course was favourable. We applied the Naranjo algorithm, with score 6 (reaction to vancomycin “probable”). Based on these results, our patient was not rechallenged.Conclusions: The purpose of this report is to highlight a rare adverse event associated with an antibiotic that is widely used in various specialties; we suggest that skin biopsy be performed in all cases of uncertain definition.