Mottled Skin

Mottled skin, or livedo reticularis, is a bluish-red net- or lace-like appearance underneath the skin. While the symptom is typically harmless and often develops after cold exposure, it can also signify a chronic medical condition.

This article discusses the symptoms, causes, and treatment options for people with mottled skin.  

What Are the Symptoms of Mottled Skin?

The only symptom of mottled skin is its appearance. Beneath the top layer of skin, discoloration occurs in a net- or lace-like pattern.

The pattern is often reddish blue or purplish in appearance. The area most often affected is the legs. However, it can also develop on the limbs, torso, and buttocks.

What Causes Mottled Skin?

Mottled skin has various causes. It develops when blood flow to the skin is interrupted or blocked in some way. When that happens, oxygen and blood become reduced in that area, causing tension in blood vessels underneath the skin.

The underlying causes depend on whether a person is experiencing primary or secondary mottled skin. Primary is typically caused by cold exposure.

Secondary mottled skin is closer associated with:

• Blood vessel diseases, including polyarteritis and Raynaud phenomenon
• Blood diseases, such as antiphospholipid syndrome (APS), Sneddon’s syndrome, and multiple myeloma
• Autoimmune diseases, such as small vessel vasculitis, medium vessel vasculitis, and temporal arteritis
• Cancers, including renal cell carcinoma, inflammatory breast cancer, and acute lymphocytic leukemia
• Connective tissue disorders such as system lupus erythematosus, Sjogren’s syndrome, and Sharp’s syndrome
• Infections such as hepatitis C, tuberculosis, typhus fever, and syphilis
• Neurological conditions such as reflex sympathetic dystrophy, Multiple sclerosis, and Parkinson’s disease
• Paralysis
• Livedoid vasculopathy
• Pregnancy

These diseases will likely present with other symptoms, depending on which one a person has when they develop mottled skin.

What Medications Cause Mottled Skin?

Some medications may cause issues with blood flow within the body, leading to mottled skin. The two most notable medications are amantadine and interferon.

Amantadine (Gocovri) treats involuntary movements in Parkinson’s disease. Interferon is an immunomodulator used to treat viral infections and conditions that develop when the immune system attacks healthy cells in the body (autoimmune disease).

Other medications that can lead to mottled skin include:

• Minocycline, an antibiotic used to treat certain bacterial infections, including sexually transmitted infections (STIs)
• Gemcitabine, a chemotherapy drug used to treat advanced ovarian cancer
• Catecholamines, which are used to control blood pressure and treat cardiac arrest
• Non-steroidal anti-inflammatories (NSAIDs), which treat inflammation

These medications may not cause mottled skin in everyone that takes them, but the symptom is considered a possible side effect.

How Is Mottled Skin Treated?

The treatment for mottled skin depends on the cause. Since the appearance of mottled skin is the only symptom, and the condition can be harmless, many people are advised to avoid cold exposure to keep it at bay.

If an underlying health disorder is to blame for the mottled skin, treatments will focus on the condition that drives the symptom instead of the symptom itself. That said, some standard therapies include:

• Rewarming the area after bouts of cold exposure
• Blood thinners and Aspirin in people with an underlying cause that could lead to blockages in blood vessels
• Quitting smoking to reduce the risk of blood clots

Are There Tests to Diagnose the Cause of Mottled Skin?

Testing for mottled skin may be complicated because of various underlying causes. For that reason, the diagnosis of the symptom is based on its appearance alone.

Once a dermatologist has determined that a person has mottled skin by looking at it, they will ask for a more thorough list of other possible symptoms and health history.

This helps to determine what other tests are required based on any other health disorders suspected.

Some possible testing that may be done include:

• Cold exposure tests
• Lupus anticoagulant panels
• Biopsies, likely a wedge or punch biopsy, to get a sample of the affected area

Further testing more specific to certain diseases will likely be required to get a definitive diagnosis of the cause.

When to See a Healthcare Provider

You should see a healthcare provider if you notice that you have mottled skin and are unsure why or when it developed.

While it is not always a cause for concern, it can occur in people with various health disorders. Seeing a healthcare provider can ensure you’re not leaving a health condition untreated.

Summary

Mottled skin is an often-benign skin disorder that presents as net- or lace-like patterns beneath the skin. Since the blood vessels are affected, the pattern's color will be bluish-reddish-purplish, depending on your skin tone.

While there are no other symptoms, people who have mottled skin may have an underlying health disorder that causes it to develop. The health condition causing mottled skin will present with its own symptoms alongside mottled skin, and because of that, testing to see what the cause is could be a lengthy and complicated process for some.

Contact a healthcare provider if you notice mottled skin developing on your legs or anywhere else on your body. They will be able to determine the cause and start treatment if need be.