# Amoxicillin-Induced Atypical Exanthema in a Patient with EBV-Related Nasopharyngeal Carcinoma: A Case Report

## TL;DR

A patient with EBV-related nasopharyngeal carcinoma developed a skin rash after taking amoxicillin, suggesting a possible link between beta-lactam antibiotics and skin reactions in such patients.

## Contribution

First reported case of amoxicillin-induced atypical exanthema in a patient with EBV-related nasopharyngeal carcinoma.

## Key findings

- The patient's EBV-DNA load increased significantly at rash onset and decreased after resolution.
- The rash resolved without long-term effects, supporting a possible correlation between amoxicillin and skin manifestations.
- The case highlights the need for caution when prescribing beta-lactam antibiotics to patients with nasopharyngeal cancer.

## Abstract

Introduction: The concomitant use of antibiotics, especially beta lactams, during acute EBV infection is widely associated with an increased risk of skin manifestations; the actual pathophysiology and prevalence of this phenomenon are still debated. Case report: We present the first reported case of atypical exanthema associated with amoxicillin intake in a patient with EBV-related nasopharyngeal carcinoma. We recorded a pattern in the plasma EBV-DNA load consisting of a significant increase at the onset of the rash with a sudden remission after its resolution. The patient recovered without sequelae. Discussion/Conclusions: The temporal relationship and the reported data on rash morphology, clinical findings and triggering factors support a possible correlation between the intake of beta-lactam antibiotics, particularly amoxicillin, and the onset of cutaneous manifestations in a patient with nasopharyngeal carcinoma. Such reactions can be a challenging differential diagnosis and may warrant increased provider consideration when choosing to prescribe beta lactams in patients affected by nasopharyngeal cancer.