[Definition of acquired toxoplasmosis infection: when is it congenital or acquired?]

Can the route of Toxoplasma gondii infection affect the ophthalmic outcomes?

Ocular toxoplasmosis is the most common cause of retinochoroiditis worldwide in humans. Some studies highlighted the idea that ocular lesions differ according to the route of infection but none of them mimicked the natural route. The current study aimed to investigate the ophthalmic outcomes in congenital and oral routes of infection with Toxoplasma in experimental animals. Mice were divided into three groups; group I: congenital infection, group II: acquired oral infection and group III: non-infected. We used Me49 chronic low-virulence T. gondii strain. We found that retina is the most affected part in both modes of infections. However, the retinal changes are different and more pronounced in case of congenital infection. The congenitally infected mice showed retinal lesions e.g. total detachment of retinal pigment epithelium from the photoreceptor layer and irregular arrangement of retinal layers. More severe damage was observed in mice infected early in pregnancy. While the postnatal orally infected mice showed fewer changes. In conclusion, the routes of Toxoplasma infection affect the ophthalmic outcomes and this may be the case in human disease. Although both are vision threatening, it seems that the prognosis of postnatal acquired ocular toxoplasmosis is better than that of congenital disease.

Toxoplasma gondii in Cattle, Camels and Sheep in Isfahan and Chaharmahal va Bakhtiary Provinces, Iran

BACKGROUND

Toxoplasma gondii is a zoonotic parasite, which is assumed to have cosmopolitan distribution.

OBJECTIVES

Adopting a cross-sectional study design the current research aimed to determine the occurrence of the parasite in cattle, camels and sheep in Isfahan and Chaharmahal va Bakhtiary provinces of Iran.

MATERIALS AND METHODS

Animals in the field and those brought for slaughter at abattoirs were included. Blood samples were randomly collected from animals and investigated by polymerase chain reaction (PCR).

RESULTS

T. gondii infections were detected in 0.00%, 6.60% and 17.9% of the sample cattle (n = 155), camels (n = 122) and sheep (n = 95) respectively. Sheep were more frequently affected in Chaharmahal va Bakhtiary (33.33%) compared to Isfahan (8.47%) (P = 0.005, 95%; CI = 6.88-43.35). No statistically significant difference was observed in infection prevalence between camels and sheep; and between the different sex categories in both camels and sheep.

CONCLUSIONS

Evidence of T. gondii occurrence in sheep and camels was provided in the provinces under study. There is a need to investigate the potential risk factors of zoonotic infections. Furthermore, animal health and production losses caused by the parasite; and associated zoonotic implications in the area under study need to be explored.

[Ophthalmic manifestations of toxoplasmosis in a human immunodeficiency virus-positive patient. Description of a case]

Toxoplasmosis is an infection of worldwide distribution caused by Toxoplasma gondii, and infects a large proportion of the world population. Only under certain circumstances of severe immunosuppression can the parasite reactivate and cause disease. The most common form of presentation of this pathology in patients with positive HIV is the brain abscess. One of the extra-cerebral forms is toxoplasmic chorioretinitis, which could lead to a chronic active form of a slowly progressive retinitis. Diagnosis is made by observing the eye fundus and confirmed by the scarring obtained after specific treatment. We report a case of a patient with diabetes and positive HIV, in whom a toxoplasmic scar injury was detected in the annual retinography follow-up. A conservative therapeutic approach was decided, with regular check-ups for possible detection of disease activation.