An exanthem is a widespread

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 ...

occurring on the outside of the body and usually occurring in

children A child ( : children) is a human being between the stages of birth and puberty, or between the developmental period of infancy and puberty. The legal definition of ''child'' generally refers to a minor, otherwise known as a person younger ...

. An exanthem can be caused by

toxin A toxin is a naturally occurring organic poison produced by metabolic activities of living cells or organisms. Toxins occur especially as a protein or conjugated protein. The term toxin was first used by organic chemist Ludwig Brieger (1849� ...

drug A drug is any chemical substance that causes a change in an organism's physiology or psychology when consumed. Drugs are typically distinguished from food and substances that provide nutritional support. Consumption of drugs can be via inhalati ...

s, or

microorganism A microorganism, or microbe,, ''mikros'', "small") and ''organism'' from the el, ὀργανισμός, ''organismós'', "organism"). It is usually written as a single word but is sometimes hyphenated (''micro-organism''), especially in olde ...

s, or can result from

autoimmune disease An autoimmune disease is a condition arising from an abnormal immune response to a functioning body part. At least 80 types of autoimmune diseases have been identified, with some evidence suggesting that there may be more than 100 types. Nearly a ...

. The term exanthem is from the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

el, ἐξάνθημα, translit=exánthēma, lit=a breaking out, label=none. It can be contrasted with

enanthem Enanthem or enanthema is a rash (small spots) on the mucous membranes. It is characteristic of patients with viral infections causing hand foot and mouth disease, measles, and sometimes chicken pox, or COVID-19. In addition, bacterial infections ...

s which occur inside the body, such as on mucous membranes.

Infectious exanthem

In 1905, the Russian-French physician Léon Cheinisse (1871–1924), proposed a numbered classification of the six most common childhood exanthems.David M. Morens. Fifth Disease: Still Hazy After All These Years
/ref> Of these six "classical" infectious childhood exanthems, four are viral. Numbers were provided in 1905. The four viral exanthema have much in common, and are often studied together as a class. They are:

Scarlet fever Scarlet fever, also known as Scarlatina, is an infectious disease caused by ''Streptococcus pyogenes'' a Group A streptococcus (GAS). The infection is a type of Group A streptococcal infection (Group A strep). It most commonly affects childr ...

, or "second disease", is associated with the bacterium ''

Streptococcus pyogenes ''Streptococcus pyogenes'' is a species of Gram-positive, aerotolerant bacteria in the genus '' Streptococcus''. These bacteria are extracellular, and made up of non-motile and non-sporing cocci (round cells) that tend to link in chains. They ...

''. Fourth disease, also known as "Dukes' disease" is a condition whose existence is not widely accepted today. It was described in 1900 and is postulated to be related to the bacterium ''

Staphylococcus aureus ''Staphylococcus aureus'' is a Gram-positive spherically shaped bacterium, a member of the Bacillota, and is a usual member of the microbiota of the body, frequently found in the upper respiratory tract and on the skin. It is often posi ...

''. In 1979 and 2001 a possible "seventh diease" was postulated following reports of a condition in Japan also referred to as acute febrile infantile mucocutaneous lymph node syndrome (MCLS). Many other common viruses apart from the ones mentioned above can also produce an exanthem as part of their presentation, though they are not considered part of the classic numbered list: *

Varicella zoster virus Varicella-zoster virus (VZV), also known as human herpesvirus 3 (HHV-3, HHV3) or ''Human alphaherpesvirus 3'' ( taxonomically), is one of nine known herpes viruses that can infect humans. It causes chickenpox (varicella) commonly affecting chi ...

(

chickenpox Chickenpox, also known as varicella, is a highly contagious disease caused by the initial infection with varicella zoster virus (VZV). The disease results in a characteristic skin rash that forms small, itchy blisters, which eventually scab ...

shingles Shingles, also known as zoster or herpes zoster, is a viral disease characterized by a painful skin rash with blisters in a localized area. Typically the rash occurs in a single, wide mark either on the left or right side of the body or face. ...

) *

Mumps MUMPS ("Massachusetts General Hospital Utility Multi-Programming System"), or M, is an imperative, high-level programming language with an integrated transaction processing key–value database. It was originally developed at Massachusetts Gener ...

rhinovirus The rhinovirus (from the grc, ῥίς, rhis "nose", , romanized: "of the nose", and the la, vīrus) is the most common viral infectious agent in humans and is the predominant cause of the common cold. Rhinovirus infection proliferates in tem ...

(the common cold) *

unilateral laterothoracic exanthem __NOTOC__ Unilateralism is any doctrine or agenda that supports one-sided action. Such action may be in disregard for other parties, or as an expression of a commitment toward a direction which other parties may find disagreeable. As a word, ''un ...

of childhood * Some types of

viral haemorrhagic fever Viral hemorrhagic fevers (VHFs) are a diverse group of animal and human illnesses in which fever and hemorrhage are caused by a viral infection. VHFs may be caused by five distinct families of RNA viruses: the families ''Filoviridae'', '' Fl ...

are also known to produce a systemic rash of this kind during the progression of the disease. *

Tick-borne disease Tick-borne diseases, which afflict humans and other animals, are caused by infectious agents transmitted by tick bites. They are caused by infection with a variety of pathogens, including rickettsia and other types of bacteria, viruses, and proto ...

s like

Rocky Mountain spotted fever Rocky Mountain spotted fever (RMSF) is a bacterial disease spread by ticks. It typically begins with a fever and headache, which is followed a few days later with the development of a rash. The rash is generally made up of small spots of bleedin ...

produce a rash that may become extensive enough so as to be classified as exanthemous in as many as 90% of children with the disease.https://www.cdc.gov/mmwr/pdf/r/rr5504.pdf

References

External links

Overview
at About.com
Definition at MedTermsDifferential diagnosis

Dermatology Quiz
Includes photo, diagnosis, and treatment of unilateral laterothoracic exanthem (ULE). {{Exanthema Dermatologic terminology

Infectious exanthem

See also

References

External links