Lupus band test is done upon
skin biopsy
Skin biopsy is a biopsy technique in which a skin lesion is removed to be sent to a pathologist to render a microscopic diagnosis. It is usually done under local anesthetic in a physician's office, and results are often available in 4 to 10 days. ...
, with
direct immunofluorescence staining, in which, if positive,
IgG
Immunoglobulin G (Ig G) is a type of antibody. Representing approximately 75% of serum antibodies in humans, IgG is the most common type of antibody found in blood circulation. IgG molecules are created and released by plasma B cells. Each IgG an ...
and
complement
A complement is something that completes something else.
Complement may refer specifically to:
The arts
* Complement (music), an interval that, when added to another, spans an octave
** Aggregate complementation, the separation of pitch-clas ...
depositions are found at the
dermoepidermal junction
The dermoepidermal junction or dermal-epidermal junction (DEJ) is the area of tissue that joins the epidermal and the dermal layers of the skin. The basal cells in the stratum basale of the epidermis connect to the basement membrane by the anchor ...
.
[Marks, James G; Miller, Jeffery (2006). ''Lookingbill and Marks' Principles of Dermatology'' (4th ed.). Elsevier Inc. .] This test can be helpful in distinguishing
systemic lupus erythematosus
Lupus, technically known as systemic lupus erythematosus (SLE), is an autoimmune disease in which the body's immune system mistakenly attacks healthy tissue in many parts of the body. Symptoms vary among people and may be mild to severe. Commo ...
(SLE) from cutaneous lupus, because in SLE the lupus band test will be positive in both involved and uninvolved skin, whereas with cutaneous lupus only the involved skin will be positive.
The minimum criteria for positivity are:
[Ther Clin Risk Manag. 2011; 7: 27–32. The lupus band test in systemic lupus erythematosus patients. Adam Reich, Katarzyna Marcinow, and Rafal Bialynicki-Birula]
* In sun-exposed skin: presence of a band of deposits of
IgM along the epidermal
basement membrane
The basement membrane is a thin, pliable sheet-like type of extracellular matrix that provides cell and tissue support and acts as a platform for complex signalling. The basement membrane sits between epithelial tissues including mesothelium an ...
in 50% of the biopsy, intermediate (2+) intensity or more.
* In sun-protected skin : presence of interrupted (i.e. less than 50%) deposits of IgM along the epidermal basement membrane, intermediate (2+) intensity or more.
The presence of other immunoglobulins (especially
IgA Iga may refer to:
Arts and entertainment
* Ambush at Iga Pass, a 1958 Japanese film
* Iga no Kagemaru, Japanese manga series
* Iga, a set of characters from the Japanese novel '' The Kouga Ninja Scrolls''
Biology
* ''Iga'' (beetle), a g ...
) and/or complement proteins (especially
C4) increases the
specificity of a positive test.
See also
*
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, blo ...
*
Skin lesion
A skin condition, also known as cutaneous condition, is any medical condition that affects the integumentary system—the organ system that encloses the body and includes skin, nails, and related muscle and glands. The major function of th ...
References
Dermatologic procedures
{{Dermatology-stub