How to treat patchy and discoloured skin.
If your skin appears blotchy with red and purple spots or a lacy network of patches, you most likely have mottled skin. Mottled skin refers to the appearance of the skin when there is a patchy discolouration to it. There are many possible causes but it is usually completely harmless.
Dr Roger Henderson looks at what causes mottled skin and possible treatments that may help:
What is mottled skin?
Livido reticularis is the medical term for mottled skin, where there is skin discolouration, typically with red or purple marks, streaks or spots. It is called reticular (‘lace-like’) because of the discoloured appearance surrounding central patches of pale skin. There may also occasionally be a ‘marbling’ appearance where the skin has different colours in the same general area.
There are many possible causes of mottled skin, and in many cases it slowly goes away over time with no treatment. However, there may be some medical reasons for it to occur which should be assessed, especially if it is accompanied by symptoms such as pain or skin ulceration.
There are many possible causes of mottled skin, and in many cases it slowly goes away over time with no treatment.
There are two main types of livido reticularis – primary and secondary. The primary type is a common form in adults, often with no obvious cause, and which can persist over time. This diagnosis is made once other potentially severe causes have been ruled out. Secondary livido reticularis (also known as livedo racemose) is associated with arrange of systemic diseases.
Mottled skin symptoms
Mottled skin is characterised by a lace or net-like pattern of skin discolouration that is classically blotchy and reddish-purple, and is most commonly seen on the legs. It may appear more vivid in colder weather, and warming the body may reduce its appearance (but not inevitably). Exposing the affected part of the skin to cold temperatures may also trigger tingling and numbness in that body area.
Newborn babies can sometimes have slightly mottled skin, often caused by getting cold. This usually settles when the baby is warmed and there is no need for any particular medical treatment.
What causes mottled skin?
In almost every case, mottle skin is caused by a disturbance of the normal blood flow to the skin. Any reduction in oxygen supply to skin cells causes an increased concentration of deoxygenated haemoglobin in the area, and this leads to the livid discolouration seen in mottled skin.
Spasm of blood vessels and problems with the circulation of the blood are two common causes of secondary livido reticularis. These include blood clots, atherosclerosis and narrowing of the blood vessels, and symptoms depend on the underlying condition – these may include leg or chest pain, fatigue and breathing difficulties. Other possible mottled skin causes include:
This is an autoimmune condition (where the body’s own immune system works against itself) that inflames the skin and blood vessels and causes mottled skin in around a quarter of sufferers. Other symptoms linked to lupus include a ‘butterfly’ shaped rash on the face, sensitivity to sunlight, fatigue, pain and stiffness of the body in general, toes and fingers that can go blue in the cold and headaches.
- Antiphospholipid syndrome
This is an autoimmune condition that affects the blood vessels, and mottled skin typically appears on the wrists or knees. Other symptoms include headaches, seizures, blood clots and strokes.
Drug-associated mottled skin has been linked to certain medications, including amantadine (a dopamine agonist used to treat Parkinson’s disease, multiple sclerosis and ADHD), the antibiotic minocycline, non-steroidal anti-inflammatories (NSAIDs) and gemcitabine.
- A cold environment
This is one of the simplest causes of mottled skin, and may also cause shivering and numbness of the skin. Warming the skin eases symptoms away.
Severe infections such as TB, syphilis, rheumatic fever and sepsis can trigger skin discolouration and mottling.
Mottled skin diagnosis
Mottled skin is normally diagnosed simply on the clinical appearance of the skin and does not require specific tests unless an underlying condition is suspected.
These include blood tests for conditions such as lupus, and a skin specialist (a dermatologist) may occasionally take a skin biopsy to examine the skin under a microscope.
Mottled skin treatment
Mottled skin treatment depends on the cause:
- In simple primary livido reticularis, no specific treatment is required apart from avoiding the cold.
- With other cases, the treatment depends on the underlying cause and can include avoiding certain medications, taking an anticoagulant and treating any infection that may be present.
- Autoimmune conditions are treated with medication designed to control the immune system and reduce inflammation in the body, and vascular problems are often treated with drugs to lower blood pressureand cholesterol levels as well as lifestyle changes.
- In all cases, smoking should be stopped in order to reduce the risk of other circulatory events occurring such as heart attacks or strokes.
In itself, simple livido reticularis is usually relatively harmless although some people with it can find their skin discolouration becomes permanent with increasing age.
If you are experiencing mottled skin and this does not go away in warm temperatures, discuss this with your doctor to see if any further investigations may be required.