A malar rash (from

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power ...

‘jaw, cheek-bone’), also called butterfly rash, is a

medical sign Signs and symptoms are the observed or detectable signs, and experienced symptoms of an illness, injury, or condition. A sign for example may be a higher or lower temperature than normal, raised or lowered blood pressure or an abnormality showi ...

consisting of a characteristic form of facial

rash A rash is a change of the human skin which affects its color, appearance, or texture. A rash may be localized in one part of the body, or affect all the skin. Rashes may cause the skin to change color, itch, become warm, bumpy, chapped, dry, cr ...

. It is often seen in

lupus erythematosus Lupus erythematosus is a collection of autoimmune diseases in which the human immune system becomes hyperactive and attacks healthy tissues. Symptoms of these diseases can affect many different body systems, including joints, skin, kidneys, b ...

. More rarely, it is also seen in other diseases, such as

pellagra Pellagra is a disease caused by a lack of the vitamin niacin (vitamin B3). Symptoms include inflamed skin, diarrhea, dementia, and sores in the mouth. Areas of the skin exposed to either sunlight or friction are typically affected first. Over ...

dermatomyositis Dermatomyositis (DM) is a long-term inflammatory disorder which affects skin and the muscles. Its symptoms are generally a skin rash and worsening muscle weakness over time. These may occur suddenly or develop over months. Other symptoms may in ...

, and

Bloom syndrome Bloom syndrome (often abbreviated as BS in literature) is a rare autosomal recessive genetic disorder characterized by short stature, predisposition to the development of cancer, and genomic instability. BS is caused by mutations in the '' BLM'' ge ...

. A malar rash of lupus is red or purplish and mildly scaly. It has the shape of a butterfly, and involves the bridge of the nose. Notably, the rash spares the nasolabial folds of the face, which contributes to its characteristic appearance. It is usually macular with sharp edges, and not itchy. There are may conditions which can cause rashes with a similar appearance to a malar rash. A malar rash is present in approximately 46–65% of people with lupus.

Definition

A malar rash of lupus is red or purplish and mildly scaly. It has the characteristic shape of a butterfly, and involves the bridge of the nose. Notably, the rash spares the nasolabial folds of the face, which contributes to its characteristic appearance. It is usually macular with sharp edges, and not itchy. The rash can be transient or progressive with involvement of other parts of the facial skin. While some literature has described the slapped-cheek rash of

fifth disease Erythema infectiosum, fifth disease, or slapped cheek syndrome is one of several possible manifestations of infection by parvovirus B19. Fifth disease typically presents as a rash and is more common in children. While parvovirus B19 can affect h ...

as a malar rash, it differs slightly in that the nose is typically spared.

Differential diagnosis

There are many conditions which can cause rashes with a similar appearance to a malar rash. These include: *

Lupus causes up to 96% of all cases of malar rash. Where lupus is suspected, further

medical test A medical test is a medical procedure performed to detect, diagnose, or monitor diseases, disease processes, susceptibility, or to determine a course of treatment. Medical tests such as, physical and visual exams, diagnostic imaging, geneti ...

s and a detailed history and examination are necessary to differentiate it from other conditions. These tests may include a test for the presence of

anti-nuclear antibody Antinuclear antibodies (ANAs, also known as antinuclear factor or ANF) are autoantibodies that bind to contents of the cell nucleus. In normal individuals, the immune system produces antibodies to foreign proteins (antigens) but not to human prot ...

in the blood as a screening test, which is not specific for lupus erythematosus.

Epidemiology

A malar rash is present in approximately 46–65% of people with lupus, with an average of 57% of lupus patients having it across all populations. This percentage varies between different populations.

History

A malar rash is often known more

colloquially Colloquialism (), also called colloquial language, everyday language or general parlance, is the linguistic style used for casual (informal) communication. It is the most common functional style of speech, the idiom normally employed in conversa ...

as a butterfly rash due to its distinctive appearance.

References

External links