Toxoplasma gondii is a single-celled parasite that infects humans and animals, including birds, cats, cattle, pigs and sheep. Among people with a normal immune system, Toxoplasma gondii infection rarely causes symptoms, although the parasite persists in the body in an inactive form. The dormant parasite may reactivate months or years later with weakening of the immune system, causing the illness toxoplasmosis. People with advanced HIV disease are susceptible to toxoplasmosis, which often affects the brain, lungs or eyes.
Headache and Confusion
Toxoplasmosis commonly affects the brain in people with advanced HIV disease, reports the medical reference text "Principles and Practice of Infectious Diseases." The Toxoplasma gondii parasite infects brain tissue, typically causing multiple abscesses, brain swelling and widespread inflammation.
Most immunocompromised patients with toxoplasmosis experience gradual development of brain-related symptoms. Common early symptoms include headache and confusion. More specific neurological signs and symptoms typically develop as the infection progresses. The brain-related symptoms of toxoplasmosis prove highly variable, as the parasite can affect any area of the brain. Most patients demonstrate involvement of multiple brain areas.
Seizures
Toxoplasmosis of the brain provokes seizures in 18 to 29 percent of HIV-infected patients, reports the medical reference website Epilepsy.com. Anticonvulsant medications control seizure activity during the symptomatic phase of the illness and may be required long term.
Muscular Weakness
People with toxoplasmosis of the brain commonly experience muscular weakness in one area of the body, reports Dr. Carlos Subauste in a March 2006 article published by the University of California, San Francisco website HIV InSite. The areas of the body affected generally correlate with sites of Toxoplasma gondii-containing abscesses in the brain.
Speech Disturbances
Speech disturbances occur in many HIV-infected patients with toxoplasmosis of the brain, note the authors of "Principles and Practice of Infectious Diseases." Slurred speech indicates involvement of the brain structures that control the muscles used in speaking.
Fever
Fever may accompany toxoplasmosis in patients with HIV, reports the Centers for Disease Control and Prevention. Notably, this symptom does not occur in all patients with the illness.
Shortness of Breath and Coughing
Toxoplasmosis can affect the lungs of people with HIV, according to MayoClinic.com. Patients typically experience gradually worsening shortness of breath and a chronic cough, which may produce blood-streaked phlegm. Pulmonary toxoplasmosis symptoms may occur along with brain-related symptoms.
Pulmonary toxoplasmosis pneumonia mimics Pneumocystis jirovecii pneumonia and tuberculosis, which also commonly affect people with advanced HIV disease. Diagnosis may prove medically challenging.
Eye Pain and Vision Loss
Toxoplasmosis can affect the eyes, causing eye pain and loss of vision. Approximately 60 percent of HIV-infected patients with toxoplasmosis of the brain also have eye involvement, according to "Principles and Practice of Infectious Diseases." One or both eyes may be affected. Vision usually improves with treatment of the infection.
References
- "Principles and Practice of Infectious Diseases, Sixth Edition"; Gerald L. Mandell, M.D., et al., Editors; 2004
- Epilepsy.com: Toxoplasmosis
- University of California, San Francisco, HIV InSite: Toxoplasmosis and HIV
- Centers for Disease Control and Prevention: Toxoplasmosis, Persons with Compromised Immune Systems
- Mayo Clinic: Toxoplasmosis Symptoms
