Toxoplasmosis in People With HIV
Toxoplasmosis is referred to as an opportunistic infection (OI) in people with HIV. This is because it only results in sicknesses when the immune system [1] has been completely compromised. You can measure the function of the immune system by the number of CD4 T-cells in your blood. The number of CD4 T-cells in a healthy person is 800 to 1,500 in a sample of blood. People with T-cells [2] lower than 200 are more susceptible to a wide variety of severe and fatal opportunistic infections.
In most cases, T. gondii in people with HIV is not newly acquired but the deactivation of previous infections. When your CD4 T-cell level goes lower than 50, the immune system will lose its ability to control the dormant bradyzoites.
The bradyzoites are usually converted back into tachyzoites and cause damage in tissues and organs. In most cases, the infection usually involves the central nervous system (CNS toxoplasmosis) and brain, the lungs (pulmonary toxoplasmosis [3]), and the eyes (ocular toxoplasmosis). Studies show that antiretroviral therapy used to treat HIV infections [4] can also prevent T. gondii from replicating. This therapy can help reduce the levels of the parasite in the body to undetectable levels, giving room for the immune system to reconstitute itself and put T. gondii under control.