[Intraocular involvement of Chagas disease (American trypanosomiasis). Studies in Paraguay/South America]

In Central and South America, Chagas' disease is of great epidemiologic importance. The epidemiologic agent is represented by Trypanosoma cruzi, a monocellular parasite, instrumental in human infection is the presence of vectors, which are various species of hematophagous bugs. The eye is one of the most important entrance sites of the parasite, and relatively little information about the relationship between Chagas' disease and eye complications is available.

We examined 79 chagasic patients in order to detect changes in the retina. As a control group, we examined 48 patients with negative serology within the same age range and from the same regions. For every patient we completed a routine ophthalmologic examination, with inspection of the retina using direct and indirect ophthalmoscopy.

In most of the chagasic patients, the ocular fundus was unobtrusive; in only 6 out of 79 cases (7.6%) we did observe small parafoveolar retinal pigment epithelium defects and in 1 case (1.3%) distinct pigment epithelium atrophy of the posterior pole. No comparable findings were observed in the control group.

Compared with the examination results of the control group, in the patients with intermediate and chronic Chagas' disease we observed an accumulation of retinal pigment epithelium defects, which, however, did not cause a significant loss of vision.