Could Toxoplasma gondii have any role in Alzheimer disease?

Alzheimer disease (AD), a chronic progressive neurodegenerative disorder, has a mainly unknown multifactorial etiology. Neuroinflammatory mechanisms might contribute to the cascade of events leading to neuronal degeneration. Central nervous system infections have been previously suggested as possible etiological agents in the development of sporadic AD. Toxoplasmosis can be associated with various neuropsychiatric disorders. In this study, we aimed to investigate the possible association between toxoplasma infection and AD.

This study evaluated the serum anti-Toxoplasma gondii IgG levels. It included an age-matched and sex-matched study and control groups that consisted of 34 patients with AD and 37 healthy individuals, respectively. There were no difference between the socio economic states of the patients and control subjects. serecm anti-I-gondi IgG levels were measured by using ELISA.

According to the statistical analysis, there were no significant differences among the patients and the control participants with respect to age (68.05±15.98, 62.91±5.89 y, P=0.072; respectively) and sex. The seropositivity rate for anti-T. gondii IgG antibodies among AD patients and control groups were 44.1% and 24.3%, respectively, and there was significant difference between the serum anti-T. gondii IgG levels (P=0.005).

Our findings suggest that toxoplasma infection may be involved in the pathogenetic mechanisms of AD. If confirmed, a positive correlation between toxoplasmosis and AD may lead to new approaches for the management of AD.