Harlequin syndrome induced by intraspinal analgesia in patients with advanced cancer: a case report.

Background: The Harlequin syndrome is an idiopathic, autonomic disorder. It typically presents with unilateral sweating and flushing of the face. It could be caused not only by autonomic dysfunction or space-occupying central neuropathy, but by some clinical interventions as well. Although iatrogenic Harlequin syndrome is rare, clinicians should be aware of this condition to diagnose correctly and provide suitable assistance. Case Description: Here we report a case of iatrogenic Harlequin syndrome. The unique part of this case is that this patient presented with successive presentations of Harlequin syndrome on different sides of the body. The patient was a 30-40-year-old woman who had flushing and sweating on one side of the face after intraspinal analgesia. This symptom disappeared on its own after a period of persistence, and reappeared several days later after increasing the dose of the drug injected into the epidural cavity. Interestingly, the second blush appeared on the other side of the patient's face. Conclusions: Triggered by intraspinal analgesia and manifested in different body parts, Harlequin syndrome is proven here to be derived from iatrogenic stimuli. We believe that the different distribution states of analgesic drugs after entering the spinal canal can promote Harlequin syndrome to manifest in different body parts.