Acrocyanosis is a painless condition where the small blood vessels in your skin constrict, turning the color of your hands and feet bluish. The blue color comes from the decrease in blood flow and oxygen moving through the narrowed vessels to your extremities.
It was first described in 1896, but is still not well understood or studied.
There are two types of acrocyanosis, primary and secondary:
- Primary acrocyanosis is associated with cold temperature and emotional stress. It’s not considered harmful.
- Secondary acrocyanosis is associated with many different underlying diseases, including eating disorders, psychiatric illnesses, and cancer.
The name comes from the Greek words akros for “extreme” and kyanos for “blue.”
What are the symptoms?
Hands and feet are the extremities most often affected by acrocyanosis. But wrists, ankles, nose, ears, lips, and even nipples may be involved.
The symptoms are symmetrical in primary acrocyanosis, affecting both hands or both feet. In secondary acrocyanosis, symptoms often affect only one side, may be painful, or may involve tissue loss.
The most common symptoms are:
- bluish-colored fingers or toes
- cold, clammy, and sweaty hands and feet
- lower skin temperatures and blood flow
- swelling of hands and feet
- normal pulse
Symptoms worsen with cold and improve with warmth. Finger color becomes normal when you move your hands to a horizontal position, from hanging down.
Most newborns have blue hands and feet right after birth and in their first few hours. The acrocyanosis symptoms may come back when the baby is cold or when the baby first comes out of a bath. But acrocyanosis doesn’t persist in infants.
What causes it?
Primary acrocyanosis is thought to be caused by the constriction of small blood vessels that decrease the flow of oxygen-rich blood to your extremities. This constriction or vasospasm has several proposed reasons for occurring, including:
- cold temperatures
- living in a high altitude with a combination of lower oxygen pressure, increased wind, and cold
- genetic defect of your blood vessels
The cause of acrocyanosis in newborns is attributed to the infant getting used to the change in blood circulation from the womb. Oxygen-rich blood initially circulates to the brain and other organs rather than to the hands and feet.
There isn’t much specific research on the causes of acrocyanosis. A 2011 study reported a lack of clarity in the medical community about whether acrocyanosis is a single disease or varies by cause.
More is known about secondary acrocyanosis because of research data on the underlying primary diseases associated with it. In some cases, acrocyanosis may be the first sign of the primary disease.
The causes of secondary acrocyanosis vary widely, and include vascular disorders, infections, blood disorders, solid tumors, genetic diseases, and some drugs.
- The most common underlying cause is Raynaud’s phenomenon, in which the extremities turn pale, then blue, and then red.
- In anorexia, weight loss may impair the body’s heat regulation. An estimated 21 to 40 percent of people with anorexia have acrocyanosis.)
- Ergot alkaloid drugs, used to treat migraines and headaches, can cause acrocyanosis.
- The mosquito-borne viral infection chikungunya can cause acrocyanosis.
- Up to 24 percent of people with cancer have acrocyanosis.
How it’s diagnosed
Your doctor will ask you about your medical history and symptoms, and then conduct a physical examination. Your diagnosis of primary acrocyanosis will be based on your hands and feet (and sometimes nose and ears) being:
- not painful
The doctor may also use capillaroscopy, a noninvasive technique that measures the circulation in the small vessels of your nail bed.
They may perform other tests to rule out Raynaud’s syndrome and chilblains, two conditions which also involve bluish extremities. Having a normal pulse indicates that the blueness is not caused by an arterial disease with impaired blood circulation.
If secondary acrocyanosis is suspected, your doctor will order other laboratory and imaging procedures to determine the primary underlying disease.
How it’s treated
There’s no standard treatment for primary acrocyanosis. Few clinical trials have looked at the effectiveness of treatment.
With newborns and infants, warming the baby is the effective treatment.
Your doctor will likely advise you to keep your hands and feet warm indoors and to protect yourself against exposure to cold temperatures.
The medical literature stresses that it’s important for doctors to reassure their patients that the condition is not harmful.
In severe cases, alpha blocker and calcium channel blocker drugs, topical nicotinic acid derivatives, or minoxidil have been used to ease symptoms.
In newborns, acrocyanosis is considered normal.
Treatment of the underlying disease may improve the symptoms of acrocyanosis.
What’s the outlook?
Primary acrocyanosis is an uncommon and benign condition with a good outlook. Some treatments are available that may lessen symptoms in severe cases.
In newborns, acrocyanosis is normal and goes away on its own.
Secondary acrocyanosis can be serious, depending on the underlying disease. See your doctor if you have symptoms of acrocyanosis. They can determine whether there’s an underlying condition that needs treatment.