Toxoplasmosis

Toxoplasmosis is caused by Toxoplasma gondii, an obligate intracellular protozoan. Up to 70% of adults have antibodies to Toxoplasma. The organism gains access to man through ingestion of contaminated food, although most infections are asymptomatic. However, immunocompro-mised patients, such as those with AIDS, organ transplants or malignancy, are predisposed to infection [28]. Pathologically, toxoplasmosis produces areas of tissue necrosis surrounded by an intense mononuclear reaction. Three patterns of CNS involvement have been described, including diffuse encephalopathy, meningoen-cephalitis and cerebral abscess. Many patients with abscess present with focal neurological signs and, in fact, toxoplasmosis is the single most common lesion, causing mass effect in AIDS patients. Toxoplasma abscesses are often multiple and bilateral. Intraparenchymal abscesses can be seen on CT and/or MRI. On CT, the lesions are characterized by a region of low density, variable adjacent edema and ringenhancement. Most lesions are subcortical, often situated in the basal ganglia. Obstructive hydrocephalus sometimes occurs, especially with large lesions near the third ventricle.

The diagnosis of toxoplasmosis is made by a combination of serological testing and tissue biopsy. The organism is best seen in tissue sections stained by the Giemsa method.

Therapy for toxoplasmosis consists of a combination of pyrimethamine and sulfadiazine, along with folic acid. In AIDS patients with multiple intracranial lesions, toxoplasmosis is the most likely diagnosis and therefore it is reasonable to begin empiric therapy and observe the patient for clinical and radiographic response. If a response is not evident within 2 weeks, then biopsy should be considered, to confirm or refute the diagnosis. Even if a response does occur, cure is generally not possible and maintenance therapy is required indefinitely to achieve the goal of therapy, namely control of the disease. Prognosis depends on the extent and severity of brain involvement and, perhaps to a greater extent, on the underlying disease process.

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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