The paper, authored by Dr. Manoj Sivan at the University of Leeds, focuses on the case of one 33-year-old man who developed with acrocyanosis—venous pooling of blood in the legs.

A minute after standing, the patient's legs began to redden and became increasingly blue over time, with veins becoming more prominent. After 10 minutes the color was much more pronounced, with the patient describing a heavy, itchy sensation in his legs. His original color returned two minutes after he returned to a non-standing position.

The patient said he had started to experience the discoloration since his COVID-19 infection. He was diagnosed with postural orthostatic tachycardia syndrome (POTS), a condition that causes an abnormal increase in heart rate on standing.

Dr. Sivan, Associate Clinical Professor and Honorary Consultant in Rehabilitation Medicine in the University of Leeds' School of Medicine, said, "This was a striking case of acrocyanosis in a patient who had not experienced it before his COVID-19 infection.

"Patients experiencing this may not be aware that it can be a symptom of long COVID and dysautonomia and may feel concerned about what they are seeing. Similarly, clinicians may not be aware of the link between acrocyanosis and long COVID.

"We need to ensure that there is more awareness of dysautonomia in long COVID so that clinicians have the tools they need to manage patients appropriately."