Saturday, October 15, 2011

Thirty Years of AIDS--Learning the AIDS Alphabet: The Letter C

Thirty (30!) Years of AIDS--Continuing to Learn the AIDS Alphabet: The Letter C

Next in the AIDS alphabet is the letter C. C stands for quite a few terms, including cancer (something AIDS patients are--or at least were--familiar with) like in KS (Kaposi's sarcoma), a type of skin cancer… C also stands for candidiasis (candidiasis in the mouth is also called thrush) and much more:

Cidofovir: This antiviral medication is similar to ganciclovir in the way it works to keep CMV from multiplying. Cidofovir is available as intravenous injections (IV). One major drawback is its a negative effect on the kidneys. Usually, an infusion with a saline solution is necessary before the use of Cidofovir.

CMV: CMV, or cytomegalovirus, can enter an individual’s body in a variety of ways, including by touching the eyes with unclean fingers. Once inside, CMV remains in the body for life, in an inactive, dormant state. When an individual’s immune system starts deteriorating and its T-cell count deeps below a certain level (50), CMV can become active. CMV can infect different organs: the eyes, lungs, esophagus, or bowels. In AIDS patients CMV mostly attacks the eyes, causing CMV retinitis, which, if left untreated, can lead to partial or total blindness. Medications used for treatment of CMV retinitis include ganciclovir, foscarnet, and cidofovir.

Journeys Through Darkness: A Biography of AIDS
Journeys Through Darkness: A Biography of AIDS, by Alina Oswald
To find out more about CMV, check out the following piece I wrote as an appendix for Journeys Through Darkness, a biography that tells the story of Kurt Weston, a fashion photographer and long-term AIDS survivor who has lost most of his sight to CMV (AIDS-related retinitis) and, in the process, become an award-winning, legally blind visual artist.

CMV Retinitis at a Glance

Flashing lights, floating spots, speckles of cotton before the eyes disturbing the sight, making it hazy and blurry as if you’re looking through a screen may or may not be early signs of blindness. These symptoms may be the first signs of an eye disease called CMV retinitis.
Retinitis means infection of the retina, the thin layer of light sensitive tissue lining the back of the eyeball. The function of the retina is to convert the optical image we see with our eyes into electrical impulses that are further sent through the optical nerve to the brain. In the case of retinitis, even if the infection is cured, scars may remain on the retina. If left untreated, retinitis can lead to partial or total blindness.
Viral retinitis (caused by a virus) is most frequent in people with weakened immune systems, like HIV/AIDS patients or cancer patients (chemotherapy treatments can weaken immunity, making the patients prone to viral retinitis). There are three viruses that are commonly responsible for viral retinitis:

Herpes simplex virus, which causes cold sores;

Varicella zoster virus (HZV or Herpes Zoster Virus), which causes chicken pox;

Cytomegalovirus retinitis, which causes total or partial blindness.
Cytomegalovirus is a kind of herpes virus that once inside the human body, it stays there for life. The virus is transmitted through bodily fluids like saliva, blood, urine, semen and breast milk, and lives peacefully in the healthy human body, in an inactive, (otherwise known as “dormant”) state, not causing disease. Most people get exposed to CMV, especially with age, without being aware that they have been infected.
When the immune system weakens, CMV can become active. For example, in a person with AIDS, when the T cell count dips below fifty (a healthy individual has approximately one thousand T cells measured per unit of blood), CMV becomes active and can attack different parts of the body, causing serious damage. The virus can cause CMV retinitis in the eye or CMV pneumonia in the lungs and it can also spread to the esophagus, stomach, and bowels.
In AIDS patients, CMV most commonly affects the eye, causing CMV retinitis, an infection affecting the retina, which swallows and inflames. As a result, the signals sent from the eye to the brain become incomplete or inaccurate, leading to blurry vision or blind spots in the vision. 
In some cases, people with CMV retinitis do not have any symptoms of the disease, sometimes even while they’re on the verge of losing their sight. That’s why it is advisable for people with very low T cell counts to go to an eye specialist for regular examinations and for a special test that checks for CMV in the eyes. Early lesions would look like small yellow-white patches with a grainy appearance, often accompanied by bleeding.
There are three standard medications used to treat CMV retinitis: ganciclovir, foscarnet, and cidofovir. CMV medications can be administered as intravenous (ganciclovir alone or in combination with foscarnet), intravitreal (injected into the vitreal fluid of the eye), as intraocular implants (surgically implanted into the eye to gradually release the drug), and also as oral medication. Oral medication is used for maintenance or as prophylaxis, to keep the CMV in check (inactive), thus reducing the risk of more damage to the retina and, therefore, preventing more vision loss.

HAART regimens, introduced in the mid-nineties, help keep the patients' immune systems healthy enough not to be prone to CMV infections. Therefore, with the advent of HAART regimens, the cases of CMV retinitis cases among people living with AIDS has decreased by almost ninety percent.


As always, thanks for stopping by!
Alina Oswald
Writer Photographer Author

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