Evanescent Hyperemia: An Underrecognized Cutaneous Manifestation of Postural Orthostatic Tachycardia Syndrome.

Postural orthostatic tachycardia syndrome (POTS) is characterized by orthostatic tachycardia with associated symptoms including presyncope, fatigue, dizziness, and gastrointestinal complaints, among others. In addition to cardiovascular and neurologic features, autonomic dysfunction may involve other organ systems. We report a rare case of transient evanescent hyperemia occurring during presyncopal episodes in a patient with POTS, highlighting a potentially underrecognized dermatologic sign of autonomic dysfunction. We present a 19-year-old female with known POTS and a complex medical history including pituitary adenoma (prolactinoma), secondary adrenal insufficiency, gastroparesis, severe malnutrition, and pelvic floor dysfunction, who was admitted for recurrent presyncope, syncope, and collapse. Her presentation was multifactorial. Contributing factors included autonomic instability, cabergoline-related effects, and nutritional compromise. During hospitalization, she developed recurrent episodes of transient, sharply demarcated erythematous patches affecting the face, chest, and upper extremities that coincided with presyncope and resolved spontaneously without intervention. Dermatology evaluation supported a diagnosis of evanescent hyperemia in the setting of autonomic dysfunction associated with POTS. Diagnostic workup included serial laboratory testing, electrocardiography, echocardiography, neuroimaging, and multidisciplinary specialty consultations. Transthoracic echocardiography demonstrated a patent foramen ovale with preserved cardiac function, without evidence of structural heart disease contributing to her symptoms. Management required a multidisciplinary approach, including stress-dose intravenous hydrocortisone for adrenal insufficiency, adjustment of cabergoline due to suspected medication-related bradycardia, continuation of fludrocortisone for volume support, and initiation of nasoduodenal tube feeding for nutritional rehabilitation. This case illustrates a transient cutaneous finding temporally associated with presyncope in a patient with POTS and complex comorbidities. Awareness of such skin changes during symptomatic episodes may provide supportive clinical clues to underlying autonomic dysfunction, particularly in diagnostically challenging presentations.