Vitrectomy update for macular traction in ocular toxocariasis

Ocular Toxocariasis: Beyond Typical Patterns through the New Imaging Technologies

PURPOSE

To report five cases of ocular Toxocariasis (OT) in which ultrawide-field (UWF) imaging was helpful in diagnosis and assessment. OT is an underdiagnosed condition triggered by the ocular invasion of Toxocara larvae. Typical features are peripheral granuloma or endophthalmitis.Methods: A retrospective case series of 10 outpatients were studied by complete ophthalmologic examination and complementary tests. UWF retinal imaging, fundus autofluorescence (FAF) and spectral-domain optical coherence tomography (SDOCT) were retrospectively analyzed. Five patients with suspected OT were included.Results: UWF imaging and FAF was able to detect all retinal lesions in a single rapid capture. Two patients showed positive serology for Toxocara. An image suggesting the larva in the vitreous cavity was shown in one patient. Antihelmintic 15 treatment along with steroids was prescribed in two patients.Conclusion: UWF imaging and SDOCT provide a more efficient approach and follow-up in OT, raising final standards of care.

Ocular Toxocariasis: Long-Term Follow-Up and Prognosis of Patients following Vitrectomy

Purpose: To investigate the outcomes of surgical treatment in patients with ocular toxocariasis and identify prognostic factors.Methods: We retrospectively reviewed the medical records of 56 consecutive patients who underwent vitrectomy.Results: The mean follow-up was 20.7 months. Visual acuity (VA) improved in 70.4% of patients by the final visit, but VA was better than Snellen 20/70 in only 31.5% of patients. Preoperative VA was closely correlated with final VA (P = 0.001). Macular involvement was associated with final VA worse than 20/70 (P = 0.03). The most common postoperative complications were ocular hypertension (19.6%) and retinal detachment (12.5%). Seven patients (12.5%) experienced recurrent inflammation postoperatively, but no preoperative factors were associated with recurrent inflammation.Conclusion: Surgical treatment could rescue visual function in patients with ocular toxocariasis but their prognosis was unfavorable. Preoperative VA was associated with final VA, whereas macular involvement was associated with poor visual outcomes.

Ocular Toxocariasis: Clinical Features and Long-term Visual Outcomes in Adult Patients

PURPOSE

To investigate clinical characteristics and treatment outcomes of proven ocular toxocariasis (OT) in adult patients.

DESIGN

Retrospective, consecutive, interventional case series.

METHODS

setting: Institutional.

STUDY POPULATION

Consecutive OT patients with positive serum serology and positive western blot (WB) on ocular sample.

OBSERVATION PROCEDURES

Clinical features, optical coherence tomography (OCT), and treatment outcomes.

MAIN OUTCOME MEASURES

Best-corrected visual acuity (BCVA) and OCT central foveal thickness (CFT).

RESULTS

Fourteen patients were included between 2011 and 2013. Mean age at diagnosis was 45.6 years. Mean duration between the first symptoms and diagnosis was 15.1 months. Uveitis was unilateral in all cases and all patients displayed vitreous inflammation. The main baseline findings were presence of ≥1 peripheral granulomas (57.1%), vasculitis (57.1%), vitreoretinal traction (57.1%), and chronic macular edema (ME) (71.4%). Delayed diagnosis (>8 months) seemed to be associated with higher rate of ME. All patients received albendazole. Systemic (n = 5) and/or local corticosteroids (CS) (n = 7) were administered in case of ME and/or posterior segment inflammation. Vitrectomy was performed when vitreous inflammation was severe and persistent despite CS or in case of threatening traction or visually significant epimacular membrane (28.6%). Overall, this regimen allowed significant decrease of CFT (P = .01). In the vitrectomy subgroup, mean BCVA increased (P = .01) and CFT decreased (P = .017).

CONCLUSION

While some features such as granuloma are typical signs of OT, atypical features can delay the diagnosis. In doubtful situations, WB on ocular samples seems to be more specific than serum antibodies alone. ME seems to be a common complication of longstanding OT in the adult.

Toxocarosis of the organ of sight - the complex pathological and diagnostic problem

Selected parasitological and epidemiological aspects of Toxocara spp. invasion were discussed. Pathomechanism of lesions and involvement of the organ of sight in toxocarosis were presented. It was stressed that pathological lesions may involve various structures of the eyeball. Moreover, the pattern of lesions may vary depending on the early or late stage of the invasion. Diagnostic techniques were presented, indispensable in confirmation of toxocarosis and establishing its duration. In diagnosis of the ocular form of toxocarosis the significance of differential diagnostic analysis was stressed, particularly essential in oligosymptomatic cases and upon coexistence of other diseases progressing with involvement of the organ of sight. This is important for further specialised management and in selection of an appropriate therapy.

A case of ocular toxocariasis successfully treated with albendazole and triamcinolon

We present a case of ocular toxocariasis treated successfully with oral albendazole in combination with steroids. A 26-year-old male visited the authors' clinic with the chief complaint of flying flies in his right eye. The fundus photograph showed a whitish epiretinal scar, and the fluorescein angiography revealed a hypofluorescein lesion of the scar and late leakage at the margin. An elevated retinal surface and posterior acoustic shadowing of the scar were observed in the optical coherence tomography, and Toxocara IgG was positive. The patient was diagnosed with toxocariasis, and the condition was treated with albendazole (400 mg twice a day) for a month and oral triamcinolone (16 mg for 2 weeks, once a day, and then 8 mg for 1 week, once a day) from day 13 of the albendazole treatment. The lesions decreased after the treatment. Based on this study, oral albendazole combined with steroids can be a simple and effective regimen for treating ocular toxocariasis.

[Ocular toxocariasis: report of two cases and review of the literature]

Toxocara canis est un nématode de la famille des Ascaridés, il peut être responsable de manifestations oculaires et générales lors d'une contamination accidentelle dans le cadre d'une pathologie du “péril fécal“, les atteintes oculaires sont plus fréquentes chez l'enfant en raison du contact souvent répété avec de jeunes animaux favorisant ainsi la dissemination de cette pathologie dite des “mains sales“, nous rapportons deux cas d'enfants présentant une toxocarose oculaire à granulome postérieur, négatif pour le sérodiagnostic spécifique. La réalisation de la ponction de la chambre antérieure et d'un test ELISA par antigènes homologues de Toxocara canis sur l'humeur acqueuse ont permis de poser le diagnostic formel.

Multifocal granulomata in presumed Toxocara canis infection in adult

Human infection of Toxocara canis in eye is usually an outcome of accidental ingestion of the embryonated eggs. The average age at diagnosis of ocular Toxocariasis is 7.5 years, ranging from 2 to 31 years. It constitutes 1%-2% of uveitis in children. Diagnosis is based upon the clinical features observed in a young patient and confirmed by the presence of specific IgG in the serum or aqueous humor by Enzyme-linked immunosorbent assay test. We report a case of Presumed Toxocara infection in 45-year-old male which is unique in presentation with multifocal granulomata in retina. Our PubMed search could not produce case with similar presentation. Probably this is the first reported case of multifocal granulomata in presumed ocular Toxocara in any age group

Ocular toxocariasis

Ocular toxocariasis is an uncommon worldwide parasitic infection that affects mostly children and is found in both rural and metropolitan areas. In many parts of the world, parasitic infections of the eye are a major cause of blindness. The diagnosis of toxocariasis is essentially clinical, based on the lesion morphology and supportive laboratory data such as serum enzyme-linked immunosorbent assay (ELISA) titers and ELISA Toxocara titers on aqueous humor; other diagnostic methods are imaging studies including optical coherence tomography, fluorescein angiography, computed tomography, and ocular ultrasound. Treatment is directed at complications arising from intraocular inflammation and vitreous membrane traction. Early vitrectomy may be of value both diagnostically and therapeutically.

Clinical characteristics of ocular toxocariasis in Eastern China

PURPOSE

To explore the clinical characteristics of patients with ocular toxocariasis in eastern China.

METHODS

The medical records of 35 cases of ocular toxocariasis in Fudan University Eye & ENT Hospital between May 2009 and April 2011 were retrospectively reviewed and analyzed. UBM, RetCam or fundus imaging, and high-frequency or conventional ultrasonography were performed in these patients.

RESULTS

The mean patient age in our series of ocular toxocariasis was 11.86 ± 8.80 years. There were 28 children and seven adults, the majority residing in a rural area (88.57%). All cases were classified into three clinical subtypes: granuloma in the peripheral retina (60% of cases); granuloma in the posterior pole (28.57% of cases); and vitreous inflammation mimicking chronic endophthalmitis (5.71% of cases). We also identified an additional subtype with unique clinical features that we termed "combined type" presenting in 5.71% of our patients. This subtype exhibited granulomas in both the posterior pole and peripheral retina. RetCam fundus imaging was able to identify granulomas in the posterior and peripheral subtypes, 100% and 80.95% of cases respectively. Moreover, UBM combined with conventional ultrasonography identified granulomas in 95% of the peripheral subtype cases and in 100% of the posterior pole subtype cases.

CONCLUSIONS

This is the first ocular toxocariasis series described in Chinese patients. Compared with reports from developed countries, the ocular features in our series were more severe and complicated, presenting with poorer visual acuity and a high rate of retinal detachment (45.7%). The application of RetCam and UBM during examination in ocular toxocariasis can provide valuable information in determining the severity of disease and features important in considering surgical procedures in such patients.

Ocular parasitic diseases: a review on toxocariasis and diffuse unilateral subacute neuroretinitis

Parasitic infections may damage various ocular tissues, thereby causing visual dysfunction. In 1950, Wilder described the first case in which larval forms of nematodal intestinal roundworms (Ascaridoidea: Ascaris, Toxocara, Ancylostoma, Necator, and Strongyloides) were implicated as a cause of intraocular disease. This review focuses on two disorders associated with parasitic infections: ocular toxocariasis and diffuse unilateral subacute neuroretinitis.

Ocular toxocariasis in Korea

PURPOSE

To analyze the characteristics and clinical manifestations of clinically diagnosed and serologically confirmed ocular toxocariasis in patients.

METHODS

Thirty-three eyes of 33 patients diagnosed as having ocular toxocariasis at the Hallym University Medical Center between January 1999 and December 2008 were included in the study. The diagnosis of ocular toxocariasis was based on clinical features and confirmed serologically by enzyme-linked immunosorbent assay and immunoblotting. All patients were interviewed by using a structured questionnaire that included risk factors that might account for the introduction of Toxocara larvae. Demographics, social characteristics determined from the questionnaire, and clinical features were evaluated.

RESULTS

A total of 33 eyes of 33 patients were enrolled in this study: 24 (73%) patients were men, and mean patient age was 41.6 ± 11.0 years. Ten of 28 patients (36%) who responded to the questionnaire had a history of contact with pets, and 23 (82%) had a history of consuming raw food. The most common symptoms were blurred vision in 22 eyes (67%) and floaters in six eyes (18%). The toxocariasis was unilateral in all patients, and the inflammation was acute in two-thirds of the patients. In 17 eyes (52%), Toxocara granuloma was found in the peripheral retina. Nineteen eyes (58%) had visual acuity of 20/40 or better at presentation and improved significantly after treatment. Final visual acuity was 20/40 or better in 26 eyes (79%).

CONCLUSIONS

Ocular toxocariasis in Korea usually affects young adults to middle-aged men. The clinical manifestation is unilateral and presents as acute inflammation with a peripheral inflammatory mass. Visual prognosis with appropriate treatment is good.

Surgical Treatment of Ocular Toxocariasis: Anatomic and Functional Results in 45 Patients

Purpose

TO evaluate the anatomic and functional outcome after surgery in patients with complicated ocular toxocariasis.

Methods

A retrospective review of the medical records of pediatric patients who underwent a surgical procedure for ocular toxocariasis from July 1990 to January 2005. Patients with postoperative follow-up shorter than 6 months were excluded from the study. Best-corrected visual acuity (BCVA) was arbitrarily divided into 5 groups: 1) no light perception (NLP); 2) light perception (LP) and hand motion (HM); 3) finger counting (FC) to 20/400; 4) 20/300 to 20/60; and 5) 20/50 to 20/20.

Results

Forty-five patients with a mean age of 8.1 years (range 6–10) were included in the study. The ocular toxocariasis presentation most commonly encountered was peripheral granuloma (38%). Twenty-one eyes presented with BCVA in the LP/HM group, 18 (40%) eyes in the FC to 20/400 group, 5 (12%) eyes in the 20/300 to 20/60 group, and 1 (5%) eye in the 20/50 to 20/20 group. The most common surgical procedure was pars plana vitrectomy (PPV) in 58% of the eyes. Four eyes (9%) presented with postoperative BCVA of NLP, 2 eyes (4%) in the LP/HM group, 12 eyes (27%) in the FC to 20/400 group, 19 eyes (42%) in the 20/300 to 20/60 group, and 8 eyes (18%) in the 20/50 to 20/20 group.

Conclusions

Surgical treatment of severe ocular complications secondary to toxocara infections results in satisfactory anatomic results and may improve the overall visual outcome of these patients.

Ocular Toxocariasis in a Seronegative Adult

Ocular nematodal infections typically affect children. This article demonstrates the utility of enzyme-linked immunosorbent assay (ELISA) testing of the aqueous humor and vitreous to aid the diagnosis of ocular toxocariasis in adults. A 62-year-old woman presented with a 2-year history of worsening vision in her left eye. Examination of the fundus revealed tractional membranes over the optic nerve and nasal retina. Serologic evaluation was unrevealing. The patient was referred to the Bascom Palmer Eye Institute for an anterior chamber ELISA, which was positive for Toxocara. A vitrectomy and scleral buckling procedure was performed. The patient achieved anatomic success after surgery, but her visual acuity in the left eye remained hand motions. This case highlights the importance and utility of ELISA testing of the anterior chamber fluid and/or vitreous aspirate for ocular toxocarasis. This patient is among the oldest described to have active ocular toxocariasis.

Treatment of ocular toxocariasis with albendezole: a case report

BACKGROUND

Toxocara canis is a parasite that can infect the eye and create a significant inflammatory response that can be detrimental to the patient's vision. Its clinical presentation can mimic other causes of uveitis, and its diagnosis and treatment can be challenging. Prompt and accurate diagnosis of ocular toxocariasis is essential to prevent permanent visual loss.

CASE REPORT

A 7-year-old Hispanic boy presented to the clinic with complaints of reduced visual acuity in the left eye. After a careful evaluation of his ocular health, he had ocular toxocariasis diagnosed and confirmed by enzyme-linked immunosorbent assay testing. Treatment with the anthelmintic, albendazole, and oral steroids was initiated. There was initial improvement of the vitritis with significant vitreous debris. However, 2 years later, reactivation occurred, and a vitrectomy was required. This case report reviews the management of a patient with active ocular toxocariasis, including clinical findings and treatment options.

CONCLUSIONS

The differential diagnosis of ocular toxocariasis and review of the available treatments are presented.

Pars plana vitrectomy revealed Toxocara canis organism

BACKGROUND

The Toxocara organism may cause direct injury to the eye, but most commonly, host inflammatory reactions are responsible for the resulting compromise. The inflammatory response created by the ocular involvement may result in epiretinal membrane formation, tractional or combined tractional-rhegmatogenous retinal detachment. The treatment of choice is pars plana vitrectomy (PPV), which also has diagnostic significance.

METHODS

We report a pediatric case in which PPV recovered the Toxocara canis organism. For the total tractional retinal detachment diagnosed after the cataract surgery, PPV, preretinal and subretinal membrane peeling, 180 degrees retinotomy, silicone oil injection were performed. The fibrous membrane specimen obtained during PPV recovered the Toxocara canis organism.

RESULTS

The intense postoperative inflammatory reaction had to be managed surgically, also. Retinal reattachment was achieved with subsequent improvement of the visual acuity.

CONCLUSION

The importance of vitreous biopsy examination following PPV, in eyes in which etiology is uncertain and the intense antiinflammatory therapy applied within and following vitreoretinal surgery is emphasized.

[Ocular toxocariasis. From biology to therapy]

Ocular toxocariasis represents an organ manifestation of the systemic infection with the Nematode larva Toxocara canis. The infection can provoke very different changes in the eye. Especially posterior uveitis, vitreous body infiltrates, epiretinal membranes and suberetinal granulomas can occur. The diagnosis of these changes can be difficult due to the variety of the symptoms and on the other side by the absence of characteristic specific changes. Moreover unclear findings can occur when only serological examinations are performed. In unclear cases the antibody-detection by means of ELISA from the vitreous body fluid can be useful. The examination of vitreous body material can prove toxocara infection when no systemic signs of infection are present and no antibodies are detectable in the serum. Besides the systemic anti-helminthic therapy with Albendazol the pars plana vitrectomy is a substantial therapeutic option in ocular toxocariasis when vitreo-retinal complications are present. A well timed adequate therapy can stabilize the visual acuity in many cases.

Prevalence, clinical features, and causes of vision loss among patients with ocular toxocariasis

BACKGROUND

To describe the prevalence, clinical features, and causes of vision loss among patients with ocular toxocariasis seen at a uveitis referral center.

METHODS

A review was completed of the charts of patients with ocular toxocariasis who were examined between 1977 and 1996 at the Francis I. Proctor Foundation of the University of California at San Francisco. The prevalence of ocular toxocariasis among all uveitis patients seen at the center was determined. Demographic features, symptoms, and signs in all patients were evaluated.

RESULTS

Ocular toxocariasis occurred in 22 (1.0%) of 2,185 uveitis patients. The mean patient age was 16.5 years. Inflammation was usually unilateral (90.9%). Toxocara uveitis presented as a granuloma in the peripheral retina in 50% of cases, as a granuloma in the macula in 25% of cases, and as a moderate to severe vitreous inflammation mimicking endophthalmitis in 25% cases. The primary causes of vision loss were vitritis (52.6%), cystoid macular edema (47.4%), and traction retinal detachment (36.8%).

CONCLUSIONS

Ocular toxocariasis is an uncommon cause of uveitis that mainly affects younger patients. Inflammation is typically unilateral and presents as either a granuloma in the peripheral or posterior retina or a moderate to severe vitreous inflammation mimicking endophthalmitis.

[Ocular toxocariasis. Diagnostic and therapeutic options]

BACKGROUND

The diagnosis of ocular toxocariasis can be difficult and the aim of this study was to evaluate the benefit of ELISA testing of vitreous body fluid.

PATIENTS AND METHODS

We present five consecutively treated patients with ocular symptoms of toxocariasis, three of these patients presenting with epiretinal membranes and subretinal granulomas were vitrectomized. Vitreous and body fluid and serum were tested for toxocara antibodies by ELISA. Moreover vitreous body fluid of 10 patients with epiretinal membranes of other origins were examined by the same ELISA.

RESULTS

In all three operated patients toxocara antibodies were detected in the vitreous fluid but ELISA testing of serum samples was negative in two of the three patients. Visual acuity increased or remained stable in the operated patients. The ELISA test was negative in all vitreous fluid samples of the control group.

CONCLUSIONS

ELISA testing of vitreous body fluid can prove the presence of toxocara infection when no systemic signs of infection are present and no antibodies are detectable in the serum. Well-timed vitrectomy is a suitable therapy for vitreo-retinal complications in ocular toxocariasis to improve prognosis and to confirm the diagnosis.

Orbital cellulitis associated with Toxocara canis in a dog

Reports of Toxocara canis ocular larva migrans are uncommon in animals, with only a few cases reported. Most reports involve larval migration into the retina and choroid, with parasitic invasion of the orbit reported only in experimental studies. This is the first clinical case of Toxocara canis infection in the retrobulbar region of a 10-year-old, cross-bred male dog presenting with unilateral orbital cellulitis. Ophthalmic signs included protrusion of the nictitating membrane, chemosis, exophthalmos and hypertropia. The parasite was diagnosed by histologic and parasitologic examination of orbital tissues, which were removed during enucleation.

Toxocara canis: egg presence in Melbourne parks and disease incidence in Victoria

PURPOSE

Toxocara canis can cause blinding eye disease. This study assessed the presence of T. canis eggs in soil from parks in Melbourne and also the incidence of presumed ocular toxocariasis in Victoria.

METHODS

One hundred and eighty soil samples were collected from nine suburban locations in Melbourne, Australia. These were analyzed for the presence of T. canis eggs. A search of laboratory records of T. canis serology requests from Victorian patients over an 8-year period was performed.

RESULTS

Only one soil sample was positive for T. canis eggs. Positive T. canis serology was reported in 13 samples from patients. These patients all had ocular features suggestive of T. canis infection.

CONCLUSION

Toxocara canis eggs are rare in public parks in Melbourne and symptomatic ocular toxocariasis is uncommon in the Victorian population. The acquisition of the disease is unlikely to be from public parks.

Nematode infections of the eye: toxocariasis and diffuse unilateral subacute neuroretinitis

In many parts of the world, parasitic infections of the eye are a major cause of blindness. The parasites Toxocara canis, Onchocerca volvulus, Taenia solium, Ancylostoma caninum, and Cysticercus celulosae all have been responsible for blinding ocular infections. The nematodes T. canis and Toxocara cati are parasitic roundworms that infect dogs (toxocarosis), other canidae, and cats. Ocular toxocariasis is an uncommon worldwide infection caused by the nematode larvae of T. canis, commonly found in dogs. Human transmission is usually via geophagia, the ingestion of food contaminated with Toxocara eggs, or contact with infected puppies, often resulting in devastating ocular or systemic effects. Ocular toxocariasis is typically a monocular disease of young children, and its clinical findings include posterior and peripheral retinochoroiditis, optic papillitis, and endophthalmitis. The inflammatory response created by ocular involvement may result in epiretinal membrane formation, traction retinal detachment, and combined traction-rhegmatogenous retinal detachment. Diffuse unilateral subacute neuroretinitis is another ocular parasitic infection that usually results in severe visual loss. Evidence suggests that diffuse unilateral subacute neuroretinitis is caused by a solitary unidentified nematode of two different sizes, but to date, only a small number of nematodes have been recovered from eyes affected with the infection. Diffuse unilateral subacute neuroretinitis occasionally can affect the fellow eye.