[The impact of the prevention of cerebral toxoplasmosis]

In France, where 70% of adults are latently infected by toxoplasma, from 20% to 40% of patients with AIDS developed toxoplasmic encephalitis until recently. The prophylactic use of drugs which are active against pneumocystis and toxoplasma has proven to be efficient. These drugs are trimethoprim-sulfamethoxazole or dapsone-pyrimethamine. With the extent of these primary prophylaxis, there is a decrease of risk of toxoplasma encephalitis; thus the rate of toxoplasma encephalitis among opportunistic infections has fallen off from 19% of the patients in 1988 to 6% in 1994, in the department of infectious diseases of the Pitié-Salpêtrière hospital. However, toxoplasmic abscesses occurring despite the prophylaxis are frequently slow growing lesions which can become huge with a moderate mass effect, mimicking the pattern of primary cerebral lymphoma. The rule of antitoxoplasmic trial treatment must be strictly followed, even under prophylaxis.