Clinical Review: Ocular Toxoplasmosis

Toxoplasmosis was the most common cause of primary retinochoroiditis. The majority of cases of ocular toxoplasmosis were congenital. However, cases of acquired ocular toxoplasmosis have been reported. The clinical manifestations of congenital ocular toxoplasmosis were choroidal coloboma, strabismus, nystagmus, ptosis, microphthalmia, cataract and enophthalmia. The purpose of this study was to determine the clinical presentation and visual outcome of 173 patients with ocular toxoplasmosis at Dr Sardjito Hospital, Dr Yap Eye Hospital, and private practice during the last six years. A total of 173 subjects were studied 98 males and 75 females. The ages at which first diagnosis was established ranged from 3 months to 68 years, frequently in young adults and occurring mostly in students. The most-reported chief complaint was blurred vision in 70.5% and floaters in 6.1% of cases. The most frequent clinical manifestations were chorioretinitis (71.2%), macular scars (22.4%), squint (6.4%), congenital cataract (2.8%), nystagmus (6.4%) and atrophic optic papilla (2.8%). Bilateral involvement was found in 32.4% of all patients. The therapeutic outcome showed improvement, especially visual acuity in acute cases (25.6%). However, visual acuity categorized as blindness was 13.9%. The results of the study imply that suddenly blurred vision in the quiet eye in the young adult, squint, and nystagmus in children could be chorioretinal inflammation and scar caused by Toxoplasma gondii. while fetal infection was found in 4,200-16,800 per year (Fernandez and Orefice, 1996). In Brazil and France, seropositivity to toxoplasmosis was found in 42-83% and 90%, respectively (Orefice and Bonfioli, 1999). Anti-toxoplasmosis prevalence in humans in Indonesia was 2-63%, and the variation depended on the city in which the sample was taken (Gandahusada, 2000). In animals, the reported prevalence of anti-toxoplasmosis was as follows: in cats 35-73%, pigs 1136%, goats 11-61%, dogs 75%, and other livestock <10% (Gandahusada, 2000). If a pregnant woman contracted a primary infection of Toxoplasma gondii, the risk that the baby would also become infected was as high as 40%. The manifestations of infection were stillbirth, miscarriage, premature delivery, or the baby suffering from congenital toxoplasmosis. Classical features of congenital toxoplasmosis were hydrocephalus, brain calcification and chorioretinal scar (Mets et al, 1996). Congenital ocular toxoplasmosis comprised SOUTHEAST ASIAN J TROP MED PUBLIC HEALTH 292 Vol 34 No. 2 June 2003 80-98% of all ocular toxoplasmosis. Most of those experienced reactivation in the 2 and 3 decades. The most common site was the macular area, which comprised about 76% of the cases (Mets et al, 1996). Perkins (1973) suggested that the prevalence of infection increased in relation to the increase in age, but in fact the infection occurred in the 2 and 3 decades. If the T. gondii infections were acquired, therefore the numbers of cases would increase according to age. Invasion through the optic nerve would cause juxtapapillaris retinochoroiditis. Relapse could be caused by more than one thing, but the latest theory suggests that toxoplasmosis reinfection is caused by infection with another, new strain of toxoplasma (Araujo et al, 1997). Location of recurrent infection occurred on the edge of the retinochoroid scars, forming one or multiple satellite lesions in the remote area. The lesion could be as deep as the retinal layers expanding to the choroid, sclera and vitreous. In some cases, the lesion could spread out into the optic nerve papilla and anterior uvea, resulting in cataract. Disturbance of macular function during developmental age could result in squint and nystagmus (Nunuk and Suhardjo, 1988). Signs and symptoms of ocular toxoplasmosis vary with age. Children were generally referred to an ophthalmologist complaining of decreased visual acuity, strabismus, nystagmus, leucocoria, choroidal coloboma and microphthalmia (Da Mata and Orefice, 2002). The typical complaint in ocular toxoplasmosis, in adolescents and adults, was blurred vision, floaters and sometimes with pain, photophobia, conjunctival hyperemia if the anterior segment was involved. The most common cause of visual loss in ocular toxoplasmosis was a macular scar, but other causes for substantial visual loss included dragging of the macula secondary to peripheral lesion, retinal detachment, macular edema, optic atrophy, cataract, glaucoma, opacification of the media, amblyopia and phthisis. Surprisingly, the presence of a large congenital macular scar can be associated with remarkably good vision (Mets et al, 1996). Acquired toxoplasmosis was rare, and about 70% of the cases of immunocompetent patients were asymptomatic. The most common manifestations were lymphadenopathy, fever, headache, malaise, pharyngitis, fatigue and night-sweats. Most acquired toxoplasmosis was asymptomatic, so that the true incidence of ocular toxoplasmosis in this setting was unclear, but current estimates range from 2-20% (Glasner et al, 1992; Couvreur and Thulliez, 1996). Toxoplasmosis in AIDS patients was rare, about 1-3 % (Jabs et al, 1989). If there were retinochoroiditis toxoplasmosis, it was often correlated with encephalitis and brain abscess (Henin et al, 1987). The latest reports disagree with the traditional pathogenesis of eye toxoplasmosis. Considerable research was develop based on research in Erechim, a small city in a farming area in Rio Grande do Soul, south of Brazil (Glasner et al, 1992). Almost all of the population in Erechim was seropositive, in contrast with a report from the South Pacific. The study in Erechim found a very high frequency of ocular abnormality and almost 18% of the population had retinochoroidal scars. Some families also had siblings who suffered from ocular toxoplasmosis. This finding was different from the study by Perkins (1973), who reported, in southern Brazil, that ocular toxoplasmosis increased in relation to increased age (Glasner et al, 1992). Two opinions have stimulated a review of ocular toxoplasmosis in Yogyakarta. The review was carried out in two referral eye clinics in Yogyakarta, which may be deemed representative of the whole of Indonesia, since many tribes from all over Indonesia live in Yogyakarta. Yogyakarta was the old capital of the State of Indonesia, 55 years ago. Now, Yogyakarta, a city of over 600,000, is the capital of Yogyakarta Province and representative of Indonesia. The majority occupations are farmer, handicraft maker and student. The purpose of this study was to determine clinical features; demography as a risk factor; management and some complications of ocular toxoplasmosis. It was hoped that the result would be useful for comparison with previous studies outside Indonesia. MATERIALS AND METHODS This study was a descriptive retrospective cohort study. The data were collected from the CLINICAL REVIEW: OCULAR TOXOPLASMOSIS IN INDONESIA Vol 34 No. 2 June 2003 293 Uveitis Subdivision and the Vitreo-retina Subdivision of Dr Sardjito Hospital, Dr Yap Eye Hospital and private practice medical records of the last 6 years. Diagnosis was established by clinical and laboratory examinations. The laboratory examinations were IgG and IgM for toxoplasmosis obtained from patients’ blood sera. Congenital toxoplasmosis was established by finding IgM in an infant’s serum, and if it were not found, the examination would be repeated 2-3 months later. Acquired toxoplasmosis was established if there were increasing IgG titers in the 3-week serial examination. Each case was followed up continuously for 3 months to track the development of the disease. Data included age, sex, occupation, chief complaint, visual acuity, clinical features, bilateral involvement, therapeutic outcome, side-effects of treatment and complications. Drug therapies administered were a combination of pyrimethamine/sulfadoxine (Fansidar), dexamethasone, and folinic acid. In special conditions, trimethoprim/sulfamethoxazole, spiramycin, clindamycin were administered as substitute therapy. Because of the length of the therapy (up to 6 weeks), side-effects need to be considered, such as leukopenia or thrombocytopenia. All of the data were tabulated and analyzed descriptively and statistically.