Colours play an important role in medical semiotics and the description of anatomical and pathological elements, and this was understood from the beginning of the practice of medical diagnosis. Most medical words related to colours come from the Greek or Latin, along with most of the prefixes and suffixes that form the beginning or end of many polysyllabic medical terms.
Let’s explore the case of the white colour.
In Latin, “white” is “alba“. “Albinism” (also called achromia, achromasia, or achromatosis) is a congenital disorder characterized by the complete or partial absence of pigment in the skin, hair and eyes due to absence or defect of tyrosinase, a copper-containing enzyme involved in the production of melanin.
The “linea alba” (“white line”) is a fibrous structure that runs down the midline of the abdomen from the xiphoid process to the pubic symphysis, composed mostly of a bright white collagen connective tissue.
The “linea alba” is a term also used in dentistry to describe a horizontal streak on the inner surface of the cheek, level with the biting plane. It usually extends from the commissure to the posterior teeth and can extend to the inner lip mucosa and corners of the mouth.
“Pityriasis alba” is a common skin condition mostly occurring in children and usually seen as dry, fine-scaled, pale patches on the face. It is self-limiting and usually only requires use of moisturizer creams. The condition is so named for the fine scaly appearance initially present (“pityr” in Greek means “bran” and “iāsis” means “disease”) and the pallor of the patches that develop.
The “tunica albuginea” is the thick fibrous white capsule of the testis and the ovaries. There is also a fibrous “tunica albuginea” that envelopes the corpora cavernosa of the penis.
The “albumins” are a family of globular proteins, the most common of which is serum albumin. Substances containing albumins, such as egg white, are called “albuminoids”.
In Greek, “white” is “leukos“. “Leukocytes” or “leucocytes” (“kytos” in Greek is “cell“) are the white blood cells. They are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders. “Leukopenia” includes a range of disorders that can cause decreases in white blood cells (“peníā” in Greek is “deficiency”). “Leukopoiesis” is the production of leukocytes (“poíēsis” in Greek means “to make”)
“Leukemia” or “leukaemia” is a group of cancers that usually begins in the bone marrow and results in high numbers of abnormal white blood cells. It derives from the Greek “leukos” (white) and “aima” (blood). The word was coined by the German Rudolf Virchow in 1845 when he was 27 years old. Virchow described in a paper entitled “Weisses Blut” (“white blood”) a patient with splenomegaly and “very few red cells and a very high proportion of colorless or white corpuscles respect to that normally found in the blood”. The literal translation of the German “Weisses Blut” into Greek was “Leukämie“. In fact, the word “leukocyte” appeared later, in 1870. Around ten years after Virchow’s findings, the German pathologist Franz Ernst Christian Neumann (1834-1918) found that one deceased leukemia patient’s bone marrow was colored “dirty green-yellow” as opposed to the normal red. This finding allowed Neumann to conclude that a bone marrow problem was responsible for the abnormal blood of leukemia patients. By 1900 leukemia was viewed as a family of diseases as opposed to a single disease.
“Leukorrhea” or “leucorrhoea” is a thick, whitish or yellowish vaginal discharge (“rhea” in Greek means “flow, flux”).
“Leukoderma” is a cutaneous condition with localized loss of pigmentation that may occur after any number of inflammatory skin conditions, burns, intra-lesional steroid injections, postdermabrasion, etc. It is largely a cosmetic problem, and is neither infectious nor contagious. The most common form is non-segmental vitiligo, which tends to appear in symmetric patches, sometimes over large areas of the body.
A “leukoma” is a dense white opacity of the cornea. It was described as “leúkōma” by the Greek physician Dioscorides in the first century AC, whose “De Materia Medica” is considered the precursor to all modern pharmacopoeias, and is one of the most influential herbal books in history. It was the main pharmacopoeia throughout the Middle Ages and Renaissance.
“Leukoplakia” (also termed “leukokeratosis”) refers to a condition where areas of keratosis appear as firmly attached white patches on the mucous membranes of the oral cavity, although the term is sometimes used for white patches of other gastrointestinal tract mucosal sites, or mucosal surfaces of the urinary tract and genitals.
“Leukodystrophy” is any of several genetically determined diseases characterized by progressive degeneration of myelin in the brain, spinal cord, and peripheral nerves. It derives from the Greek “leuko” (white), “dys” (bad, ill, abnormal) and “trophos” (feeder).
Vitiligo is a condition that causes depigmentation of parts of the skin. It occurs when skin pigment cells (melanocytes, see below) die or are unable to function. It is a disease known for a long time: the first mention of a loss of skin pigmentation is found in Egypt in 1500 BC. The Latin word vitiligo was apparently coined by the Roman encyclopedist Celsus in his book of medicine written in the first century BC. There are two hypotheses on the origin of this word. One says that it derives from “vitium“, meaning “vice” or “default’. The other, saysthat it derives from “vitelius” meaning “lamb”‘, which refers to the characteristic white calves. By the late nineteenth century, the Hungarian dermatologist Moritz Kaposi (1837-1902) defined the vitiligo as a pigment dystrophy.
Alfredo E. Buzzi