acute toxoplasmosis

Background: Chronic toxoplasmosis has been shown to be strongly associated with a range of neuropsychiatric effects including schizophrenia and suicide. However there have not been any prospective, community-based studies of the neuropsychiatric effects of acute toxoplasmosis in adult immunocompetent patients. Methods: Adult patients with a positive serum IgM anti-Toxoplasma gondii test result, in the context of an acute illness with lymphadenopathy, were invited to complete a questionnaire seeking information relating to the nature, severity, and duration of symptoms in the months following the diagnosis of acute toxoplasmosis. Results: Laboratory testing identified a total of 187 adults who had a positive serum IgM anti-T. gondii test result between 1 January and 30 November 2011. Consent to contact 108/187 (58%) patients was provided by their family doctor; 37 (34%) of these 108 patients completed and returned the questionnaire. Questionnaires from the 31/108 (29%) patients who reported swollen lymph nodes during their illness were included in the study. Fatigue (90%), headache (74%), difficulty concentrating (52%), and muscle aches (52%) were the most commonly reported symptoms. These symptoms commonly persisted for at least 4 weeks. Twenty-seven of 31 (87%) subjects reported a moderate or severe reduction in their overall physical and mental health during the first 2 months of illness. Conclusions: Acute toxoplasmosis in immunocompetent adults commonly causes moderately severe neuropsychiatric symptoms that might result from replication of the organism in the central nervous system with consequent effects on brain function. Patients should be advised that such symptoms are common and reassured that they usually resolve completely within a few months.