Acrocyanosis

Description

• Painless, symmetric, distal bluish discoloration usually affecting hands and occasionally feet (1)
  • Peripheral parts: Ear, nose, and nipple can be affected.
  • Affected areas can be cool.
• Often secondary to underlying cause (2)
• Unlike Raynaud phenomenon (RP), acrocyanosis is continually persistent.
  • RP has a broad differential but is distinct from acrocyanosis and is differentiated by the waxing and waning of extremity discoloration.

Epidemiology

Incidence
Unknown, uncommon

Prevalence

• Mostly affects persons <30 years old
• Typically more common in colder climates, with increased outdoor exposure, and in people with lower BMIs

Etiology and Pathophysiology

Unknown, several theories

• Vasospasm of arteries and arterioles with secondary dilatation of capillaries and veins, leading to cyanosis (2)

Genetics
Unknown

Risk Factors

• Low BMI
• Outdoor exposure in cold climates

General Prevention

• Keep hands and feet warm.
• Wear additional socks and gloves (fingerless gloves for work).

Commonly Associated Conditions

Associated conditions may occur with secondary RP and include the following:

• Connective tissue disease (systemic lupus erythematosus [SLE], scleroderma, etc.)
• Occlusive peripheral vascular disease. Buerger disease is an advanced case.
• Drugs: SSRIs, TCAs, vasopressors, α-agonists (cocaine, amphetamines), ergotamines, nicotine, some chemotherapeutic agents
• Hematologic causes: cold agglutinins, polycythemia, paraproteinemias, cryoglobulins, cryofibrinogens
• Trauma and vibration: pneumatic tools, damage to distal arteries
• Environmental exposure: chilblains (pernio), frostbite

History

• Painless blue fingers, hands, nose, lips, toes, or feet
• Digits may often feel cool.
• Symptoms worsen with cooler temperatures.
• Onset typically in 2nd or 3rd decade
• Symptoms are long-standing but not generally progressive.
• Can be associated with hyperhidrosis of hands (“sweaty palms”)

Physical Exam

• Cyanosis of affected areas, usually distal hands and feet
• Bilateral involvement
• Peripheral pulses are strong.
• No trophic changes (no loss of hair) nor ulcerations

Differential Diagnosis

• RP
• Staining of skin (Consider wiping the skin with an alcohol swab.)
• Chilblains
• Livedo reticularis
• Peripheral neuropathy affecting vascular flow
• Complex regional pain syndrome (previously reflex sympathetic dystrophy or causalgia)
• Occlusive arterial disease (usually affects only one limb and is progressively painful)

Diagnostic Tests & Interpretation

Initial Tests (lab, imaging)

• All tests are typically normal with acrocyanosis, but it is a diagnosis of exclusion and usually needs further evaluation to rule out secondary cause of acrocyanosis.
• Capillary oximetry
• Complete blood count (CBC)
• If concerned about connective tissue diseases, CBC, antinuclear antibody (ANA), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) to screen
• If concerned about hypercoagulable state: anticardiolipin antibodies, prothrombin gene mutation, proteins C and S, factor V Leiden, antithrombin III, and others
• CMP and/or metabolic screening
• CT, MRI, NCV, and so forth

Follow-Up Tests & Special Considerations
None

Diagnostic Procedures/Other

• In general, none
• Ankle-brachial index and duplex ultrasound if concerned about peripheral arterial disease (PAD)
• Consider evaluation for asymmetric involvement (arteriography for abnormal anatomy; e.g., coarctation of aorta).

General Measures

• Keep extremities warm with insulated clothing.
• Behavioral changes to avoid inciting situations: outdoor weather without warm clothes, sitting under the AC at work, smoking cessation, and so forth
• α-Blockers or calcium channel blockers
• Patient education and reassurance is quite helpful.

Medication

First Line

• Generally not indicated (1,2)[C]
• Avoid vasoactive medications.
• Limited evidence suggests medications that block peripheral catecholamines (i.e., β-blockers) may be beneficial.

Issues For Referral

• Only in cases where the diagnosis is uncertain
• Consider dermatology, rheumatology, or vascular surgery as appropriate.

Follow-up Recommendations

• Most patients do well.
• Progression to digital or limb ulceration or pain does not typically occur with acrocyanosis. If so, reconsider diagnosis to include vasculitis syndromes.

Patient Monitoring

• None required
• Patients may engage in normal activity and employment.
• Patients should modify their dress to keep distal extremities warm.

Diet

• Nothing specific
• If patients notice worsening with sympathomimetics (caffeine, decongestants), adjust accordingly.

Patient Education

Reassurance is the best policy.

Prognosis

Excellent; does not progress or worsen; often resolves in middle age

ICD-10

• I73.89 Other specified peripheral vascular diseases

ICD-9

• 443.89 Other specified peripheral vascular diseases

SNOMED

• 25003006 acrocyanosis (finding)