[Extensive toxoplasmic retinochoroiditis. Diagnostic and therapeutic management]

INTRODUCTION

To assess the diagnostic and therapeutic management of extensive toxoplasmic retinochoroiditis.

PATIENTS AND METHODS

The files of all patients referred between December 1999 and December 2001 for the management of a severe, potentially sight-threatening toxoplasmic retinochoroiditis were retrospectively analyzed. The therapeutic strategy and the progression of intraocular inflammation are reported.

RESULTS

Thirteen eyes of seven patients were finally included in the study. The sex ratio (F/M) and the mean age were respectively 4/3 and 44.5 years. Most of the patients were immunocompromised. Both eyes were initially affected in five cases. The diagnosis was confirmed by polymerase chain reaction (PCR) after anterior chamber paracentesis in six cases. Retinal detachment was observed in three cases, initially or during follow-up. All patients were treated with a combination of sulfadiazine and pyrimethamine, but azithromycin was necessary in two cases. Clindamycin was used in two cases of allergy to sulfadiazine. Corticosteroids were associated in five cases. For all patients, infection and inflammation were finally controlled. The visual acuity improved more than two lines in four eyes and remained stable in seven other eyes.

DISCUSSION

Clinical diagnosis is still a challenge in severe cases of extensive toxoplasmic retinochoroiditis. PCR is helpful in identifying Toxoplasma gondii DNA. A systemic immunosuppression is frequently associated with a positive PCR. Treatment is based on a standard antiparasitic association and steroids must be discussed for each case according to the intensity of inflammation and the degree of immunosuppression.

CONCLUSION

Extensive ocular toxoplasmosis is a serious condition. The final prognosis depends on the location of the necrotic lesions, rapid diagnosis, and efficient treatment.

Toxoplasmosis transmitted to a newborn from the mother infected 20 years earlier

PURPOSE

To present a case of congenital toxoplasmosis in a newborn whose mother had a 20-year history of a chorioretinal macular scar and positive serology for toxoplasmosis.

DESIGN/METHODS

Case report. SETTING/RESULTS: A 38-year-old woman who had been treated for ocular toxoplasmosis 20 years earlier delivered a newborn who presented with a focal necrotizing retinochoroiditis characteristic of toxoplasmosis, as well as positive immunoglobulin (Ig) G and M serology for toxoplasmosis. The workup was negative for other entities.

CONCLUSION

This case suggests that women with old retinal scars due to toxoplasmosis and long-standing IgG antibodies to toxoplasmosis are also at risk of transmitting this disease to the fetus.

[Acute ocular toxoplasmosis--case report]

The authors a case with uveoretinal toxoplasmosis, in a immunocompetent patient. There are some discussions about treatment and evolution in such cases.

Antibiotics for toxoplasmic retinochoroiditis: an evidence-based systematic review

PURPOSE

To determine the effectiveness of systemic antibiotic treatment for toxoplasmic retinochoroiditis.

CLINICAL RELEVANCE

Toxoplasma retinochoroiditis is a significant cause of visual morbidity. Multiple different antibiotic regimens are used, but controversy about treatment effectiveness remains.

LITERATURE REVIEWED

Searches were conducted of Cochrane Controlled Trials Register, Medline (1966 onward), Embase (1980 onward), Dissertation Abstracts (1861 onward), Lilacs (1982 onward), and Pascal (1984 onward). Pharmaceutical companies were contacted for unpublished data. Any randomized controlled trials that compared antibiotics versus placebo in immunocompetent patients with toxoplasmic retinochoroiditis were retrieved. Primary outcome measures were long-term visual acuity and risk of recurrent retinochoroiditis. Secondary outcomes included duration and severity of acute symptoms, size of the lesion at end of follow-up, and adverse effects of treatment.

RESULTS

Only 3 studies (total of 173 participants) were randomized controlled trials and hence met the inclusion criteria (level II). All 3 were methodologically poor, and 2 were carried out more than 35 years ago. None reported the effect on long-term visual outcome. We found no evidence for a beneficial effect on the duration and severity of signs of acute toxoplasmic retinochoroiditis (A,II). There was weak evidence for an effect of long-term treatment for chronic recurrent toxoplasmic retinochoroiditis on lesion recurrence. Treatment was associated with adverse effects.

CONCLUSIONS

There is a lack of evidence to support routine antibiotic treatment for acute toxoplasmic retinochoroiditis. Placebo-controlled randomized trials of antibiotic treatment in patients presenting with acute or chronic toxoplasmic retinochoroiditis arising in any part of the retina are required.

Toxoplasma gondii retinochoroiditis after cardiac transplantation

PURPOSE

To report 4 cases of Toxoplasma gondii retinochoroiditis in patients having recently undergone cardiac transplantation.

METHODS

Review of medical records for 4 patients presenting retinochoroiditis and evidence of T. gondii infection.

RESULTS

Patient ranged in age from 25 to 53 years. Ocular symptoms began between 3 and 6 months after transplantation. All patients were under immunosuppressive therapy. Foci of retinochoroiditis were observed unilaterally in three patients and bilaterally in one. Intraocular inflammation was minimal in all cases. Serologic responses were highly suggestive of T. gondii as the etiology in all cases; other causes (CMV retinitis and syphilis) were actively sought and were not found. All patients underwent classic therapy. The three unilateral cases evolved favorably, but the bilateral case, seen late, showed extensive macular scarring.

CONCLUSION

Infectious retinochoroiditis is a potentially blinding complication seen after cardiac transplantation, justifying close clinical and serological surveillance or, in certain cases such as mismatched donors, anti-parasitic prophylaxis.

Surgery for subfoveal choroidal neovascularization in toxoplasmic retinochoroiditis

PURPOSE

To report a case of subfoveal choroidal neovascularization in a patient with toxoplasmic retinochoroiditis who underwent surgical excision.

DESIGN

Interventional case report.

METHODS

A 36-year-old woman with toxoplasmic retinochoroiditis presented with sudden dimness of vision and metamorphopsia in the left eye. The patient was examined with ophthalmoscopy and fluorescein angiography.

RESULTS

Fundus examination and fluorescein angiography of the left eye revealed a subfoveal choroidal neovascularization. Pars plana vitrectomy with submacular surgery was performed, with a postoperative improvement of visual acuity and resolution of the distortion.

CONCLUSIONS

This case report describes a case of subfoveal choroidal neovascularization associated with toxoplasmic retinochoroiditis that responded remarkably well to vitrectomy surgery.

Pediatric uveitis

Uveitis in children is an entity most pediatricians and ophthalmologists seldom encounter. It is prevalent in society, however, and the high incidence of sight-threatening complications in untreated children warrants a baseline knowl-edge of the diseases and disorders involved as well as a sense of when to refer to a specialist.

[Clinical and therapy features of ocular toxoplasmosis in patients with HIV-AIDS infection]

The paper presents clinical and therapy features of the ocular Toxoplasmosis in patients with HIV-AIDS infection. Four cases of AIDS have been observed in witch has been recognized the ocular toxoplasmosis (two at children and two at adults). It was watched the evolution under treatment of the lesions caused by the parasite and it was appreciated the efficiency of the therapy.

CONCLUSION

The antitoxoplasmosis therapy is made in the same way as at the immunocompetents patients, but it must be followed by a maintenance treatment all the patience's life.

Presumed toxoplasmosic anterior optic neuropathy

PURPOSE

To describe the clinical findings and course of toxoplasmic anterior optic neuropathy and to differentiate primary and secondary involvement.

METHODS

Retrospective observational case series from a tertiary referral institution. Clinical and photographic charts of 13 patients with toxoplasmosis with direct optic nerve head involvement were reviewed and data were collected throughout the length of follow-up.

RESULTS

Toxoplasmic anterior optic neuropathy was divided into two types. Type I was defined as secondary infectious involvement of the optic nerve head from an adjacent focus of chorioretinitis that resolved with chorioretinal scarring. Type II was defined as primary involvement of the optic nerve head that resolved without chorioretinal scarring. Visual acuity improved after treatment in both Type I and Type II patients; however, the visual prognosis was worse in Type I patients due to macular involvement. Eighty-three percent of Type II patients had a final visual acuity equal to or better than 20/25 compared to 50% of Type I patients. Visual field defects were present in all patients, most frequently arcuate or altitudinal (62%). Delay in diagnosis was common (54%), especially in Type II patients (71%). Vitreous inflammation was absent on the initial examination in 31% of the patients.

CONCLUSION

Toxoplasmic anterior optic neuropathy is an uncommon manifestation of ocular toxoplasmosis. Delays in diagnosis are common because of the frequent lack of typical chorioretinitis or vitreous inflammation. Adjacent macular involvement strongly influences visual outcome.

Ocular toxoplasmosis presenting as neuroretinitis: report of two cases

BACKGROUND

Neuroretinitis is a clinical entity usually seen in young healthy adults, that is characterized by rapid profound unilateral loss of vision and includes optic nerve head edema, splinter hemorrhages, macular exudate in a stellate pattern, and variable vitreous inflammation. There are numerous entities that can cause a picture of neuroretinitis ranging from vascular to infectious to autoimmune.

PATIENT AND METHODS

We report two patients with neuroretinitis, who presented with unilateral blurred vision and had serologic evidence of Toxoplasma gondii infection.

RESULTS

Both patients responded well to treatment with systemic antibiotics and corticosteroids. Visual acuity returned to 20/60 in one patient and 20/20 in the other.

CONCLUSION

Although the etiology is usually idiopathic, infectious causes of neuroretinitis, including toxoplasmosis, should be kept in mind in order to maintain visual acuity by early diagnosis and appropriate therapy.

Ocular toxoplasmosis

Toxoplasmosis is the most common infectious cause of posterior uveitis. Although the classic presentation including moderate to severe vitreous inflammation associated with a focal retinochoroiditis and an adjacent or nearby retinochoroidal scar offers little diagnostic difficulty, numerous atypical presentations have been recognized. Here, both serologic and PCR-based analyses can be used to support the diagnosis in clinically challenging cases. Treatment decisions can be complex and need to be individualized for each patient.

An update on current practices in the management of ocular toxoplasmosis

PURPOSE

To update information that was published by the AMERICAN JOURNAL OF OPHTHALMOLOGY in 1991 about treatment practices for ocular toxoplasmosis by uveitis specialists.

DESIGN

Physician survey.

METHODS

A written questionnaire was distributed to all physician-members (n = 147) of the American Uveitis Society. The questionnaire was modeled after a similar device used to survey uveitis specialists in 1991. Information contained on 96 returned questionnaires was tabulated.

RESULTS

Among 79 respondents who evaluate and manage patients with ocular toxoplasmosis, 15% treat all cases regardless of clinical findings (in contrast to 6% in 1991). The major indications for treatment among other respondents were severe inflammatory responses and proximity of retinal lesions to the fovea and optic disk. The majority of clinical factors considered in five categories (vision, lesion location, lesion size, lesion characteristics, and vitreous inflammatory reaction) were identified to be relative or absolute indications for treatment by a greater proportion of respondents in the current survey than in the 1991 survey. A total of nine drugs (or commercially available combinations) were used in 24 different regimens as treatments of choice for typical cases of recurrent toxoplasmic retinochoroiditis, with the combination of pyrimethamine, sulfadiazine, and prednisone being the most commonly used regimen (29% of respondents).

CONCLUSIONS

Uveitis specialists appear to be more likely to treat patients with ocular toxoplasmosis in 2001 than in 1991. Although the majority of survey respondents adhere to a traditional approach to the management of toxoplasmic retinochoroiditis (a discrete course of systemic drug treatment during active disease using multiple antiparasitic drugs with or without corticosteroids), there is still no consensus regarding the choice of antiparasitic agents for treatment regimens. Survey results provide useful information for treating physicians and for clinical investigators interested in therapy.

A prospective, randomized trial of pyrimethamine and azithromycin vs pyrimethamine and sulfadiazine for the treatment of ocular toxoplasmosis

OBJECTIVE

To compare the effects of two treatment regimens, one of which included azithromycin, for the treatment of sight-threatening (near optic disk or fovea) ocular toxoplasmosis.

DESIGN

Prospective, randomized open-labeled multicenter study, masked in part with regard to evaluation.

METHODS

PARTICIPANTS TOTAL ENROLLMENT: 46 patients with sight-threatening ocular toxoplasmosis; pyrimethamine and azithromycin group: 24 patients; pyrimethamine and sulfadiazine group: 22 patients.

INTERVENTION

Patients were randomized into two treatment regimens. Group 1 was treated with pyrimethamine and azithromycin complemented with folinic acid and the addition of prednisone from day 3. Group 2 was treated with pyrimethamine and sulfadiazine complemented with folinic acid and the addition of prednisone from day 3. Patients used study medications daily for 4 weeks. Ocular and laboratory examinations were performed at least weekly during the observation period. The study was masked in part with regard to evaluation.

MAIN OUTCOME MEASURES

An assessment was made of the time to resolution of the intraocular inflammatory activity, the size of the retinochoroidal lesion, and visual acuity before and after the treatment as well as all adverse effects of treatments.

RESULTS

Adverse effects were more frequent in the pyrimethamine/sulfadiazine group (P <.04), and three patients in this group had to discontinue treatment. The time to resolution of inflammatory activity, decrease in size of retinochoroidal lesions, and optimal visual acuity did not differ between the two treatment groups. The number of patients who developed recurrences during the first year after treatment was similar for both groups.

CONCLUSIONS

The efficacy of the multidrug regimen with pyrimethamine and azithromycin was similar to the standard treatment with pyrimethamine and sulfadiazine. However, the frequency and severity of adverse effects was significantly lower with a regimen containing pyrimethamine and azithromycin. Multidrug therapy with the combination of pyrimethamine and azithromycin appears to be an acceptable alternative for treatment of sight-threatening ocular toxoplasmosis.

The effect of long-term intermittent trimethoprim/sulfamethoxazole treatment on recurrences of toxoplasmic retinochoroiditis

PURPOSE

To determine the effect of long-term intermittent trimethoprim/sulfamethoxazole treatment on recurrences of toxoplasmic retinochoroiditis.

DESIGN

Prospective randomized open-labeled interventional clinical trial.

METHODS

A total of 124 patients with a history of recurrent toxoplasmic retinochoroiditis were randomized to treatment with one tablet of trimethoprim (160 mg)/sulfamethoxazole (800 mg) (Bactrim F; Roche Pharmaceuticals, Rio de Janeiro, Brazil) every 3 days (61 patients) or to observation without treatment (63 patients) and were followed monthly for up to 20 consecutive months for clinical signs of disease recurrence. A recurrence was defined as a new focus of necrotizing retinochoroiditis with active inflammation either adjacent to or remote from preexisting retinochoroidal scars.

RESULTS

Recurrences developed in four (6.6%) treated patients and in 15 (23.8%) controls (P =.01). Treatment was discontinued prematurely in four patients because of mild drug reactions.

CONCLUSION

Long-term intermittent treatment with trimethoprim/sulfamethoxazole can reduce the rate of recurrent toxoplasmic retinochoroiditis.

[New trends in ocular toxoplasmosis--the review]

For past ten years some new trends can be observed in the field of ocular toxoplasmosis. In this article on the basis of reviewing scientific articles the author tried to point out important, or new information which may have an impact on clinical researches and clinical practice in the close future. 1. There is evidence that some tissue cysts can be present in untouched retinal tissue, and can produce an inflammatory reaction even many years after primary infection. This concerns both congenital and acquired toxoplasmosis. 2. The coexistence of intraocular inflammatory reaction without focal necrotizing retinochoroiditis in patients with acquired systemic toxoplasmosis was described--but there is no evidence that those inflammations were directly cause by T. gondii parasite themselves. It is too early to include this changes into the classical clinical picture of toxoplasmic retinochoroiditis. 3. For the past ten years there have been published articles showing higher prevalence of acquired ocular toxoplasmosis but this is well documented only in south America. In Europe and USA the frequency of ocular toxoplasmosis cases are low. Despite the different percentage of infected people in these populations, this controversial result can be caused by different distribution of pathogenic and non-pathogenic strains of the parasite as like by differences in human genotypes. 4. There is model of "dynamic equilibrium" existing between host defence and parasite cyst ruptures helpful for understanding reactivation. Level of tissue cyst-specific antigens does not rise in the population of HIV patients or during reactivation of ocular retinochoroiditis--this places the responsibility for reactivation on the side of host immunoresponse. 5. The most specific and reliable laboratory assessment for ocular toxoplasmosis, which is specifically helpful in clinically atypical cases, is combination of IgG, IgA and IgM serology tests made of serum and intraocular fluids. It can proof intraocular production of antibodies. PCR tests have got some value, but they are not as efficient as have been thought previously. 6. There is no efficient treatment diminishing recurrence rate and the time of singular inflammation yet. The combination of pyrimethamine, sulfadiazine and clindamycin, given for 3 to 4 weeks with supplementation of folinic acid for diminishing side effects, can diminish the measure of future scar. Long lasting treatment as it is used in children with congenital disease or in HIV patients can be probably more efficient. Atovaquone is as effective as traditional drugs and gives fewer side effects.

Ocular toxoplasmosis: clinical features and prognosis of 154 patients

PURPOSE

To ascertain the clinical features, visual outcome, and recurrence rates of ocular toxoplasmosis (OT) in a large series of patients. To determine the efficacy of various treatment strategies and identify the patients at risk of visual loss.

DESIGN

Retrospective noncomparative observational case series.

PARTICIPANTS

One hundred fifty-four consecutive patients with active lesions of OT (first attack and/or recurrence) were identified in a cohort of 1300 consecutive patients with uveitis. Mean follow-up was 5.8 years.

INTERVENTION

A review of the medical records of 154 patients with active OT.

MAIN OUTCOME MEASURES

Patients were subdivided according to clinical and laboratory criteria. Numerous variables were compared per patient and group, including age and gender distribution, onset and course of infection, clinical ocular features, laboratory data, therapeutic strategies and their outcomes, number of recurrences, complications, final visual acuity, and features associated with poor visual outcome.

RESULTS

Primary retinal lesions were observed in 28% and a combination of active lesions and old retinochoroidal scars in 72% of the patients at first presentation to the ophthalmologist. Mean age at first presentation with an active OT lesion was 29.5 years. Patients with primary OT were older than those with a combination of active lesions and old scars (P < 0.001). Serologic characteristics of the acute phase of systemic infection were found in 11% of the patients. Ocular involvement in these patients was associated with advanced age at onset (P < 0.001) and was characterized by severe intraocular inflammation. Most (82%) of the patients with serologic characteristics of the acute phase of systemic infection had primary lesions (compared with 23% of OT in the chronic phase of systemic infection; P < 0.001). Extensive retinal lesions were more frequently observed during the acute phase of systemic infection (P = 0.02) and in patients with primary OT (P < 0.04). Recurrences, which developed in 79% of all patients followed for more than 5 years, were located predominantly in previously affected eyes (with old scars) in contrast to the sporadic cases of recurrence in the healthy contralateral eye (P < 0.0001). Standard short-term therapeutic modalities had no effect on visual outcome or future recurrence rates. Legal blindness in one or both eyes was confirmed for 24% of the patients. Blindness of both eyes was more frequent in patients with congenital OT (P < 0.001). Risk factors for visual loss included congenital infection, OT manifesting during the acute phase of systemic infection, central location and/or extensive retinal lesions, and the administration of corticosteroids without a shield of antiparasitic drugs.

CONCLUSIONS

Legal blindness in at least one eye developed in 24% of the patients with OT. Recurrences, which developed in 79% of the patients with long-term follow-up, were located predominantly in eyes with toxoplasmic scars. Various short-term therapeutic modalities had no effect on visual outcomes or future recurrence rates, with the exception of a poor visual outcome for patients who received corticosteroids without a shield of antiparasitic drugs.

Ocular toxoplasmosis after the fifth decade

PURPOSE

To describe the clinical features in patients presenting with ocular toxoplasmosis after the fifth decade and to analyze laboratory findings in comparison to uveitis history and clinical data.

DESIGN

Prospective consecutive observational case series.

METHODS

A prospective clinical analysis of 27 consecutive patients older than 50 years of age with primary or recurrent ocular toxoplasmosis was performed during a period of 8 years. These cases account for 12% of all ocular toxoplasmosis cases irrespective of age indexed in our institution during the same period. Paired serum and aqueous humor samples were tested for anti-Toxoplasma gondii IgG, IgM, and IgA antibodies. The presence of T. gondii DNA in aqueous humor was determined by polymerase chain reaction followed by DNA hydridization method.

RESULTS

Although similar in age, two groups were distinguished clinically: 12 patients (44%) presented with usual forms of retinochoroiditis (mean +/- SD, 1.6 +/- 0.5 disk areas [DA] in size); 15 patients (56%) presented with atypical lesions, greater than 3 DA in size (mean +/- SD, 5.0 +/- 2.0 DA). The second group showed a higher rate of complications (P =.028) and a poorer visual outcome (P =.015). Twenty-four patients (89%) had intraocular IgG production, 17 (63%) had intraocular IgA production, 3 (11%) had intraocular IgM production, and 12 (44%) had a positive T. gondii DNA detection.

CONCLUSIONS

After the fifth decade, ocular toxoplasmosis remains an important cause of posterior uveitis. The combination of antibody detection by immunocapture tests with T. gondii DNA detection, both in aqueous humor, allowed the diagnosis of toxoplasmic infection in the atypical cases with large ocular lesions.

Hypersensitivity reaction to intravitreal clindamycin therapy

A Caucasian woman presenting with recurrence of intra-ocular toxoplasmosis was given intravitreal clindamycin. She subsequently developed a hypersensitivity reaction in the form of a generalized erythematous rash. To the authors' knowledge, hypersensitivity reactions to an antibiotic given by the intra-vitreal route have not previously been reported.

Antibiotics versus control for toxoplasma retinochoroiditis

BACKGROUND

Acute toxoplasma retinochoroiditis causes transient symptoms of ocular discomfort and may lead to permanent visual loss. Antibiotic treatment primarily aims to reduce the risk of permanent visual loss, recurrent retinochoroiditis, and the severity and duration of acute symptoms. There is uncertainty about the effectiveness of antibiotic treatment.

OBJECTIVES

The objective of this review was to compare the effects of antibiotics versus placebo or no treatment for toxoplasma retinochoroiditis.

SEARCH STRATEGY

We searched the Cochrane Controlled Trials Register - CENTRAL/CCTR, which contains the Cochrane Eyes and Vision Group Specialised Register (Cochrane Library Issue 2, 2001), MEDLINE (1966 to August 2001), EMBASE (1980 to September 2001), Dissertation Abstracts (1861 to June 2001), LILACS (1982 to 1998), Pascal (1984 to March 2000), proceedings of the Association for Research in Vision and Ophthalmology (1980 to 2001), international symposia on uveitis, and reference lists of review articles. Pharmaceutical companies were contacted for unpublished trials.

SELECTION CRITERIA

We included randomised controlled trials that compared any systemic antibiotic treatment against placebo or no treatment. Trials that included immunocompromised patients were excluded.

DATA COLLECTION AND ANALYSIS

The primary outcomes for this review were visual acuity at least three months after treatment and risk of recurrent retinochoroiditis. Secondary outcomes were improvement in symptoms and signs of intraocular inflammation, size of lesion and adverse events. Effect measures were pooled using a random effects model.

MAIN RESULTS

Three trials, which randomised a total of 173 participants, met the inclusion criteria. All trials were methodologically poor. None reported the effect of treatment on visual acuity. Two studies reported results for recurrent retinochoroiditis: one (124 participants) found a significant reduction in participants with chronic recurrent disease who were treated for 14 months: relative risk 0.28 (95% confidence interval 0.10 to 0.78); the other (20 participants) found no evidence of an effect in participants with acute toxoplasma retinochoroiditis (relative risk 1.00, 95% confidence interval 0.07 to 13.87). Two studies reported an improvement in intraocular inflammation in treated compared with untreated participants and one study reported no difference. Two studies found an increased risk of adverse events in treated participants.

REVIEWER'S CONCLUSIONS

There is a lack of evidence to support routine antibiotic treatment for acute toxoplasma retinochoroiditis. There is weak evidence to suggest that long-term treatment of patients with chronic recurrent toxoplasma retinochoroiditis may reduce recurrence. Placebo controlled trials of patients with acute and chronic toxoplasma retinochoroiditis affecting any part of the retina are required to determine the effectiveness of antibiotic treatment.

Atypical anterior optic neuropathy caused by toxoplasmosis

PURPOSE

To report atypical anterior optic neuropathy due to toxoplasmosis.

METHODS

Interventional case report. A 33-year-old male presented with sudden painless loss of vision and floaters in the right eye. Examination demonstrated a best-corrected visual acuity of 20/200, optic nerve head edema, retinal hemorrhages, and vitreous opacities.

RESULTS

Nine days later, a granuloma at the optic nerve head was apparent, and the patient was treated with pyrimethamine, sulfadiazine, folinic acid, and prednisone. Six weeks after initiating therapy, best-corrected visual acuity had improved to 20/25.

CONCLUSION

Optic nerve involvement in toxoplasmosis is uncommon and, when it occurs, usually presents with a white inflammatory mass on the optic disk. The current case demonstrates the importance of including toxoplasmosis in the differential diagnosis of unilateral anterior optic neuropathy, even if a focal inflammatory mass is not apparent.