Long Covid can lead to ‘blue legs’ – study

A rehabilitation medicine specialist has identified one of the more unusual symptoms of long Covid – a case where a patient’s legs now turn blue after just 10 minutes of standing.

The research, led by Dr Manoj Sivan, associate clinical professor and honorary consultant in rehabilitation medicine at the University of Leeds, focused on the case of one 33-year-old man who developed with acrocyanosis, or venous pooling of blood in the legs.

The paper, published in The Lancet, concluded that the patient’s legs began to redden and became increasingly blue over time, with veins becoming more prominent.

After 10 minutes the colour was much more pronounced, with the patient describing a heavy, itchy sensation in his legs. His original colour returned two minutes after he returned to a non-standing position. The patient said he had only started to experience the discolouration following a Covid-19 infection.

He was diagnosed with postural orthostatic tachycardia syndrome (POTS), a condition that causes an abnormal increase in heart rate on standing.

Acrocyanosis has previously been observed in children with dysfunction of the autonomic nervous system (dysautonomia), a common symptom of post-viral syndromes.

Dr Sivan 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,” he added.

Previous research by Dr Sivan’s team has shown that both dysautonomia and POTS frequently develop in people with long Covid.

Dysautonomia is also seen in a number of other long-term conditions such as fibromyalgia and myalgic encephalomyelitis, also known as chronic fatigue syndrome or ME.

Dr Sivan said: “We need more awareness about dysautonomia in long-term conditions; more effective assessment and management approaches, and further research into the syndrome. This will enable both patients and clinicians to better manage these conditions.”