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MourkaCat t1_irbgx51 wrote

Reply to comment by BallardRex in What happens when a bruise heals? by DwagonFyre

Is the staining what makes bruises look brown/yellow/green as it heals?

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Helmut_Vonscapin t1_irbqjmo wrote

Bilirubin is a brown/yellow compound produced by the degradation of hemoglobin. Various concentrations lead to various fading colours

Edit : see the answer of SadandFurious, it is much better

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Nomicakes t1_irby70t wrote

Unusual but related question, would a regularly-high Bilirubin count (showing in a blood test) cause bruises to fade slower?

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Not_Keurig t1_irco07v wrote

Clinical scientist here, I analyze bilirubin (and other things) in blood.

An abnormally high bilirubin makes people look yellow, or "jaundiced." Also, high concentrations make your blood plasma (the liquid part of your blood) look much darker than normal. (Most plasma is light yellow, similar to urine). But a high bilirubin plasma will be dark yellow to green to black! And it stains the glass test tubes with its color. Interesting and not really something I knew till I started my career. Thought I could share

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Kiavu t1_irdxg15 wrote

if anyone is curious, people who have abnormally high bilirubin generally have a condition called Gilbert's Syndrome.

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erwinscat t1_irdzmik wrote

>Gilbert's Syndrome

Which is mostly harmless/asymptomatic (and very common), apart from intermittent jaundice and some possible links to fatigue and other diffuse symptoms.

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Monguce t1_irepv3x wrote

It might be more accurate to say that people who have Gilbert's are often jaundiced.

There are loads of causes of juandice. Some of them are really bad news.

It can be pre hepatic (like haemolysis), intra hepatic (like Gilbert's) or post hepatic (like gall stones).

Other things that you'd have to consider would include drug reactions, pregnancy, biliary obstruction, autoimmune causes (haemolysis, hepatitis...) Other causes of hepatitis (viral, anaesthetics, alcoholic...), I forget the rest of the list. It's not hard to find out you want to know the other causes.

The most likely causes are also different at different ages.

Gilbert's is one of many.

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Kiavu t1_irgreo4 wrote

Absolutely, all it takes is a blood test to diagnose. I have gilbert's, but had no idea until a doctor noted it during a blood test for something else. I had always wondered why sometimes by eyeballs were yellow like I had cancer, or my skin got yellower sometimes.

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Beautiful-Ice7622 t1_ird75ir wrote

Is it possible that the black samples are coming from people who have tattoos? I know in the heavily tatted cadavers, the lymphatic fluid is grey/black. The ink gets stuck and circulates. Idk anything about the color patterns of bilirubin but it would be really freaking interesting if that were why your samples were black.

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Not_Keurig t1_irde1kr wrote

That's a really interesting thought! But it's not the same reason. Lymph would obviously be more affected by tatoo ink, as macrophages engulf the metal in the tattoo ink, and then return to the lymph.

Really interesting to learn that about lymph. very much appreciate the additional info, but no, the high bilirubin making plasma look dark yellow, greenish or kinda black (called "icteric") is only from bilirubin.

Also it's not really black, just a very very dark greenish yellow.

Additionally, some medications can make the plasma look kind of green.

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dnick t1_ireqa7x wrote

The lymphatic system is over of the least talked about complete systems in the body. It's like those illustrations of the circulatory systems and the nervous systems and then years later biology teachers are like 'oh, yeah, there's another one too' and then right back to floating over it.

Seems like it's that way because it was so elusive anatomically and low key for the most part, but just like hormones are crazy important to how we work, the lymphatic system is crazy important to how things keep working. I think most people, if they even think about it, assume everything flows back directly into the circulatory system, but aside from gasses, that seems like mostly an outbound channel.

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rvralph803 t1_ircixr4 wrote

Bilin, a byproduct of breaking down hemoglobin. It's also why poop is brown.

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twoRay t1_ire1kvx wrote

Also the colour of the bruise depends on the colour of your skin. As your skin obviously overlaps the bruise and causes a distortion in the colour.

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