Ahmed Y. Hatata, MSc Rowayda M. Amin, MSc Assistant Lecturer Ophthalmology Alexandria University, Egypt Toxocariasis

History A 28 year old male patient complaining of diminution of vision in the right eye A 28 year old male patient complaining of diminution of vision in the right eye Medical history: free Medical history: free Surgical history: ureter stone surgery 2 months ago Surgical history: ureter stone surgery 2 months ago Family history: free Family history: free Drug history: free Drug history: free

First Presentation - Ocular Examination  BCVA: 6/12 OD 6/6 OS  Anterior segment:  Unremarkable OU  Fundus:  O.S.: free  O.D.: white epiretinal mass  close to the fovea with a fibrous band connecting it to the disc

First Presentation - FLA  Hyperfluorescent epiretinal mass with increasing fluorescence in late phases due to staining  Tortuous retinal vessels towards the mass due to fibrous tissue traction  Late pooling of the dye around the mass due to mild tractional retinal elevation

First Examination - OCT

First Presentation – Lab Findings  eosinophilia  positive serology for toxocara antibodies (indirect ELISA IgG)

Diagnosis Toxocariasis induced Uveitis

Treatment  no treatment due to  granuloma outside of the fovea  no systemic manifestations  no signs of inflammation  close follow up  did not show up again

Pathogenesis  Caused by infestation with toxocara canis, a common intestinal roundworm of dogs  Infection occurs secondary to ingestion of food contaminated with the ova shed in the dogs faeces  In the intestine the ova proliferate into larvae which penetrates the intestinal wall and spread to different organs like the eye

Ocular toxocariasis - 3 forms  Chronic endophthalmitis like picture  Posterior pole granuloma  Peripheral granuloma  Less common manifestations include: anterior uveitis, papillitis and localized vitreous abscess

Chronic endophthalmitis  Presentation: between 2 and 9 years of age with leukocoria, strabismus  ant. Uveitis  Vitritis  peripheral retina and pars plana: dense grey white exsudate similar to a snowbank  Complications: TRD and cataract  Prognosis: poor  Treatment: periocular steroids, surgery

Peripheral granuloma  Presentation: during adult life with visual impairment from macular distortion or RD  if uncomplicated it may remain asymptomatic, or  white hemispherical granuloma  anterior to the equator in any quadrant of the fundus  vitreous bands may extend from the lesion to the post. pole causing  dragging of the disc and straightening of the blood vessels

Posterior pole granuloma  Presentation: unilateral visual impairment  rounded yellow white solid granuloma  one to two discs in diameter  overlying the macula  occasionally may involve the disc  no uveitis  Complications: vascular distortions and exudations, subretinal haemorrhages and may be RD