Acute papillitis in young female with toxoplasmosis.

Papillitis and complicating acute toxoplasma retinochoroiditis, are unusual and atypical features of toxoplasmosis. This report presents a female with unusual acute papillitis. This patient had an active toxoplasmic chorioretinitis lesion that appeared to involve the optic nerve head and a major blood vessel as well as central nervous systems (CNS). Papillitis may be secondary to juxtapapillary retinitis (Jensen choroiditis). Very rarely, the optic nerve head may be the primary site of involvement. This case report illustrates a rare presentation of acute papillitis in a young immunocompetent female.

INTRODUCTION

Ocular toxoplasmosis is a common cause of infectious retinochoroiditis worldwide.1–3 Toxoplasmic retinochoroiditis classically presents as a focus of new retinitis adjacent to an old chorioretinal scar.4 Retinal lesions are usually found adjacent to blood vessels. Toxoplasmic optic neuropathy is rare, characterized by subacute visual loss and optic nerve swelling, at times accompanied by a macular star (neuroretinitis). Toxoplasmosis produces multifocal lesions in the central nervous system with a predilection for the basal ganglia and the frontal, parietal, and occipital lobes. Intracranial calcification may be seen on computed tomography (CT). Magnetic resonance imaging (MRI) scanning typically shows multiple lesions that are isointense with the brain on TI-weighted images and isointense or hyperintense on T2-weighted images. Fluorescein angiography (FA) does not usually contribute significantly to the diagnosis in typical case; however, it is helpful in demonstrating associated features such as vasculitis, vascular occlusion, arteriovenous shunt within the retina, retinochoroidal shunts, macular edema and choroidal neovascular membranes, as well as optic nerve and neuroretinal involvement.4–6 Toxoplasmic retinochoroiditis is one of the most common causes of posterior uveitis, especially in young patients.7–9 The infection can be congenital or acquired. Ocular symptoms vary according to the age of the subject. For example, young children present with reduced visual acuity, strabismus, nystagmus, and leukocoria. Teenagers and adults complain of decreased vision, floaters, photophobia, pain, and hyperemia.8 Toxoplasmic retinochoroiditis typically affects the posterior pole, and the lesions can be solitary, multiple or satellite to a pigmented retinal scar. Active lesions present as a gray-white focus of retinal necrosis with adjacent choroiditis, vasculitis, hemorrhage, and vitreitis. Cicatrization occurs from the periphery toward the center, with variable pigmentary hyperplasia.9 Anterior uveitis is a common finding, with mutton-fat keratic precipitates, fibrin, cells and flare, iris nodules and posterior synechiae. Atypical presentations include punctate outer retinitis, neuroretinitis, papillitis, pseudo-multiple retinochoroiditis, intraocular inflammation without retinochoroiditis, unilateral pigmentary retinopathy, Fuchs’-like anterior uveitis, scleritis and multifocal or diffuse necrotizing retinitis.1011 Lifelong antitoxoplasmosis treatment is necessary to prevent recurrence. This case report presents the clinical outcome of a patient with acute optic neuropathy with anti- toxoplasmosis treatment.

CASE REPORT

A 32-year-old HIV-negative woman was referred to the neuro-ophthalmology department with sudden visual loss and retro-ocular pain in left eye that increased with eye movement. She had a history of intractable headache and vertigo. Best corrected visual acuity (BCVA) was 20/40 in the right eye and 20/200 in the left eye. Color vision was reduced in both eyes. Anterior segment examination was normal in the right eye but revealed a mild inflammation in the left. Intraocular pressure was within the normal limits bilaterally. Both fundii had hyperemic optic disc edema, swelling, associated peripapillary hemorrhages, and bilateral neuritis. The left fundus demonstrated an old scar from toxoplasma retinochoroiditis with a new whitish retinochoroidal lesion at the upper end of the optic nerve head [Figure 1]. Laboratory workup results included an erythrocyte sedimentation rate of 6 mm in the first hour (reference range 1–12), and normal white blood cell count. Lumbar puncture (LP) was performed. Serological testing for toxoplasmosis was negative for IgM but IgG titres were 60 IU/ml (reference range >3). Serology tests for Treponema pallidum, and HIV were normal. Fluorescein angiography showed early optic disc diffuse hyperfluorescence in both eyes and branch retinal artery and vein occlusion with late leakage overlying and adjacent to the disc in the left eye. Automated perimetry demonstrated right optic disc enlargement and depression in sensitivity. Automated perimetry of the left eye demonstrated a diffuse depression in sensitivity with a cecocentral scotoma and inferior arcuate defect. T1-weighted axial magnetic resonance imaging (MRI) scan and fluid-attenuated inversion-recovery (FLAIR) MRI of the brain, demonstrated a few tiny non-specific high signal foci in the hemispheric white matter . The patient was treated with sulphadiazine (4 × 1 g/day), pyrimethamine (2 × 25 mg/day) and folinic acid over 6 weeks. Topical steroids and mydriatic drops were also prescribed for inflammation of the left eye. Prednisone (1 mg/kg) was introduced, at tapering doses, during the treatment. After 3 months, visual acuity returned to 20/20 without correction in both eyes. Anterior segment examination was normal. Examination of the posterior segment of the left eye showed regression of the hemorrhages and a white chorioretinal scar.

Figure 1

Figures of 32 year old woman. (a and b) color photographs showing severe hyperemia ,elevation and hemorrhages, (c and d) fluorescein angiography shows early diffuse hyperfluorescence, (c1 and d1). late leakage overlying and adjacent to the disc, Intraretinal dye leakage which an arrow showed (e and f) Automated perimetry demonstrates the enlargement and depression in sensitivity. (g) Axial T1 Brain MRI, (h) Axial fluid-attenuated inversion-recovery was shown a few tiny unspecifi c high signal foci at hemispheric white matter, (i) Axial proton density, (j) axial T1 with contrast

DISCUSSION

A search of peer reviewed English literature yields few well documented cases of papillitis and complicating acute toxoplasma retinochoroiditis.1213 The term papilledema refers to true edema of the optic nerve head due to increased intracranial pressure (ICP). The appearance of the disc in papilledema is indistinguishable from that in other causes of true edema (e.g., papillitis), which includes nonspecific optic disc edema. True optic disc edema usually demonstrates hyperemia, dilation and telangiectasia of the surface disc capillaries and may be associated with flame hemorrhages on or adjacent to the disc. When disc edema and decreased vision is present, the differential diagnosis should include anterior ischemic optic neuropathy (AlON), papillitis, intraorbital compression, central nervous system (CNS) infections and lesions. The workup of acuity and visual field loss and true optic disc edema should include lumbar puncture, imaging of the course of the optic nerve (brain MRI, CT scan). The prognosis mainly depends on rapid identification of the site of inflammation and pathogen to install effective antimicrobial treatment as early as possible. Whereas analysis of CSF, laboratory analysis and neuroimaging remain the gold standard to identify the infectious agent (e.g.,, in meningitis). The filling pattern during angiography, of the edematous optic nerve head, may provide additional diagnostic information. Cerebral toxoplasmosis is the rare cerebral lesion in HIV negative patients. Infected patients are seropositive for anti-Toxoplasma antibodies. This case report documents uncommon clinical signs of the focal active toxoplasmosis chorioretinitis lesion that appeared to involve the optic nerve as well as juxtapapillary areas. T. gondii occurs worldwide, but its incidence is higher in tropical areas and decreases with increasing latitude.6 The retina seems to be the primary site of T. gondii infection, with secondary choroidal involvement producing retinochoroiditis.7 Optic nerve involvements in toxoplasmosis are uncommon and when it occurs, usually presents with a white inflammatory mass on the optic disc.8 Variations in disease characteristics may be related to host, parasite, or environmental factors. The genotype of the infecting parasite appears to be an important determinant of disease severity in immunocompetent patients. Secondary prophylaxis may reduce the rate of recurrences in high-risk patients.9 The diagnosis of toxoplasmic chorioretinitis in immunocompetent adults usually is made by ophthalmoscopic detection of a solitary focus of active chorioretinitis adjacent to a chorioretinal scar.1011 The involvement of the optic nerve most frequently found in ocular toxoplasmosis was optic nerve edema with a concurrent distant active lesion. The second type of lesion most often found was juxtapapillary retinochoroiditis. Involvement was monocular in most cases and the visual prognosis was favorable. Patients with toxoplasmic chorioretinitis may develop features suggestive of choroidal ischemia that can result in a transient or permanent decrease in vision. Choroidal ischemia can only be suspected clinically and fluorescein angiography is required to establish the definitive diagnosis. On follow-up, clinical resolution of retinal whitening and thickening were noted in the affected area in this case.

The possible differential diagnosis of this case included toxoplasmosis, tuberculous meningitis, and cerebral brain abscess, postviral and infectious neuritis, idiopathic demyelinating neuritis , intracranial mass, hydrocephalus, central nervous system infection (such as bacterial or viral meningitis or(meningoencephalitis), infiltration by a granulomatous or malignant process, or pseudo tumor cerebri (which may be idiopathic, medication induced, or related to cerebral venous obstruction). Major features differentiating this case of toxoplasmosis papillitis include: The optic disc was hyperemic, with obscuration of the nerve fiber layer, blurred the margin of the disc, with peripapillary retinal hemorrhage, presence of anti-toxoplasma antibodies in the blood and in the CSF, normal standard tests of CSF specimens, automated perimetry demonstrates diffuse depression in sensitivity with a scotoma and inferior arcuate defect, CT and MRI imaging results include a few tiny unspecific high signal foci at hemispheric white matter. Gadolinium administration reveals enhancement, serologic testing for other specific infections were negative. Suspicion of papilledema warrants urgent neuroimaging to rule out an intracranial mass lesion. Diagnosis made based on the presence of anti-toxoplasma antibodies in the blood and in the CSF. After ruling out all possible differential diagnoses, this case with bilateral optic neuropathy was diagnosed with toxoplasmosis based on serology and was responsive to anti-toxoplasmosis treatment.