Hematoidin is a yellow-brown pigment that results from the breakdown of hemoglobin. Its spelling is pronounced with four syllables, "hee-muh-toid-in," and is written phonetically as /hiːməˈtɔɪdɪn/. The first syllable is pronounced with a long "e" sound followed by a schwa sound. The second syllable has a short "a" sound, and the third syllable has a long "o" sound followed by a schwa sound. The final syllable has a short "i" sound followed by a nasal "n." Spelling can be tricky, but the IPA transcription can help clarify the pronunciation.
Hematoidin is a noun that refers to a yellowish-brown crystalline substance derived from the breakdown of hemoglobin, the protein responsible for carrying oxygen in red blood cells. It is a pigment associated with the breakdown of blood in certain pathological conditions, particularly in cases of severe hemorrhage or blood extravasation.
When hemoglobin is broken down after red blood cells are destroyed, it is converted into bilirubin, a yellow pigment that is eventually transformed into hematoidin. This substance can accumulate in various tissues and organs, particularly in areas where there has been bleeding or tissue damage. Hematoidin is commonly found in old blood clots, bruises, and certain medical conditions such as hematomas or hemopericardium.
The characteristic yellowish-brown color of hematoidin can be observed when it stains tissues, indicating the presence of blood breakdown products. Microscopically, it appears as amorphous granules or needle-like crystals. This pigment is often associated with the healing stage of tissue injuries and may be found in the surrounding tissues of a healing wound or injury.
Overall, hematoidin is a substance that plays a role in the normal breakdown of blood components, particularly hemoglobin. Its presence and identification can be helpful in diagnosing and understanding certain medical conditions related to bleeding and tissue damage.
An iron-free substance resulting from the splitting up of hematin in the phagocytic digestion of the effete erythrocytes; it is apparently identical in chemical composition with bilirubin; it may be formed independently of cell-activity and is found in the remains of old blood extravasations and clots.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.
The word "hematoidin" is derived from the Greek words "haîma" (meaning blood) and "eîdos" (meaning form or shape). The suffix "-in" typically denotes a substance or derivative. In the case of "hematoidin", it refers to a yellow pigment derived from the breakdown of hemoglobin in the blood.