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a picture of sickle cell disease

Sickle cell disease is an autosomal recessive genetic disorder, predominantly affecting African-American individuals, that causes deformity of the red blood cells.  These deformed red blood cells get stuck in and block off the capillaries (the smallest blood vessels), thus preventing adequate blood flow (and therefore oxygen) from reaching the tissues of the body.  This blockage of small blood vessels is what causes the characteristic pain associated with sickle cell disease.  

We’ve all heard of sickle cell disease, but what is really going on?  What does it look like?  Here are some electron microscope pictures demonstrating the actual difference between normal red blood cells and sickle red blood cells:

 

The difference in the shape of the cells is clear and quite stunning!

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4 Responses to “a picture of sickle cell disease”

  1. 1
    r:

    Shouldn’t you really be saying that this disease affects African peoples and to a lesser extent, native Meditteranean residents?

    Good photo

  2. 2
    mudphudder:

    In the United States, sickle cell disease predominantly affects African-Americans and Hispanics to a lesser extent (approximately one order of magnitude less prevalence). Worldwide, sickle cell disease is most prevalent in the those of African decent. Your comment piqued my interest in the worldwide prevalence of sickle cell disease so I searched for it all over (e.g. pubmed and WHO) but could not find any exact numbers. However, I strongly suspect that the prevalence of sickle cell disease in those of mediterranean descent is considerably lower than that of people of African descent. The prevalence of sickle cell disease is well characterized in persons of African descent–according to the World Health Organization up to 1 in 50 in some African countries and approx. 1 in 400 in the U.S. However, all reports of sickle cell disease in persons of mediterranean descent I have seen are case series of ~50 to 100 patients. If you find a good reference for sickle cell disease in the mediterranean people, please let me know.

    Also, yes–I agree, the pictures are pretty cool!!! Thanks!!!

  3. 3
    r:

    The point I am making is that, globally Africans (i.e. those in Africa rather than the Americas) are most susceptible to this disease, numerically speaking. The reason you won’t find exact numbers is that, like malaria, it is a ‘neglected’ disease and as such data is not as readily available. Your citation of WHO data proves my point clearly: “…predominantly affecting African-American individuals…” is mis-leading. The total numbers of Africans in only some states (maybe west Africa alone?) with sickle cell disease is likely to be greater than the whole of USA!

    I mention Meditteranean people only in term of geographic vicinity.

  4. 4
    mudphudder:

    Numbers aren’t well known in the white population but as I mentioned the epidemiology has been relatively well tracked in Africans (and in the U.S., African-Americans and Hispanics). Here is a WHO document I looked at: http://www.who.int/gb/ebwha/pdf_files/WHA59/A59_9-en.pdf
    Moreover, sickle cell disease isn’t an issue of susceptibility. It’s a recessive genetic trait–and actually, yesterday I saw one large scale study in the US from 2000 that actually noted a sickle cell carrier frequency of ~2 orders of magnitude lower in whites compared to African Americans, so you can imagine then how much more rare the disease would be in whites.
    I agree with you that much more can be done in understanding sickle cell disease. As you mentioned, the prevalence of SCD is amazing in some areas of West Africa.
    I don’t think I’ve read this much about sickle cell disease since maybe first year of medical school–7 years ago!

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