Crowned dens syndrome developed after an endoscopic retrograde cholangiopancreatography procedure.

We present a unique case of crowned dens syndrome (CDS) that developed after endoscopic retrograde cholangiopancreatography (ERCP) in a patient who presented with fever and neck pain. Administration of non-steroidal anti-inflammatory drugs was extremely effective for relieving fever and neck pain, and in the improvement of inflammatory markers. To the best of our knowledge, this is the first case report of CDS caused by an ERCP procedure. In a patient with fever and neck pain after an ERCP procedure, CDS should be considered in the differential diagnosis.