Diffuse unilateral subacute neuroretinitis with unusual findings

Diffuse Unilateral Subacute Neuroretinitis: Challenges in Diagnosis and Management

We report two cases of diffuse unilateral subacute neuroretinitis (DUSN) where multimodal imaging was used to assist in locating the nematode. The first case presented with clusters of migrating choroiditis with a suspicious tiny visualized worm noted on serial fundus photography. The second case had an atypical presentation with extensive exudative retinal detachment and a suspicious coiled worm in the subretinal space noted on optical coherence tomography. Both cases received oral albendazole for six weeks while the first case received additional argon laser photocoagulation to the suspected nematode. Both cases showed resolution of the ocular inflammation upon completion of treatment with no further recurrences. DUSN should be suspected in young and healthy patients with unexplained unilateral inflammatory eye disease with severe loss of vision. This series highlights the challenges faced in identifying the nematode in cases with suspected DUSN.

[Unilateral optic atrophy in a 9-year-old patient]

Ein 9‑jähriger Patient stellte sich aufgrund einer seit 2 Wochen zufällig bemerkten Sehminderung auf dem linken Auge vor. Funduskopisch waren neben einer leichten Vitritis eine blasse Papille, enggestellte Gefäße und eine Reflexvermehrung der Netzhautoberfläche sichtbar. In der Blutuntersuchung waren die Werte bis auf eine Eosinophilie und einen erhöhten Immunglobublin E(IgE)-Antikörpertiter normal.

Update on pathology of ocular parasitic disease

Parasites are a group of eukaryotic organisms that may be free-living or form a symbiotic or parasitic relationship with the hosts. Consisting of over 800,000 recognized species, parasites may be unicellular (Protozoa) or multicellular (helminths and arthropods). The association of parasites with human population started long before the emergence of civilization. Parasitic zoonotic diseases are prevalent worldwide including India. Appropriate epidemiological data are lacking on existing zoonotic parasitic diseases, and newer diseases are emerging in our scenario. Systemic diseases such as cysticercosis, paragonimiasis, hydatidosis, and toxoplasmosis are fairly common. Acquired Toxoplasma infections are rising in immune-deficient individuals. Amongst the ocular parasitic diseases, various protozoas such as Cystoidea, trematodes, tissue flagellates, sporozoas etc. affect humans in general and eyes in particular, in different parts of the world. These zoonoses seem to be a real health related problem globally. Recent intensification of research throughout the world has led to specialization in biological fields, creating a conducive situation for researchers interested in this subject. The basics of parasitology lie in morphology, pathology, and with recent updates in molecular parasitology, the scope has extended further. The current review is to address the recent update in ophthalmic parasites with special reference to pathology and give a glimpse of further research in this field.

Clinical experience in treatment of diffuse unilateral subretinal neuroretinitis

Purpose

To describe the clinical features, management, and outcomes of patients with diffuse unilateral subacute neuroretinitis (DUSN).

Methods

A noncomparative, consecutive analysis of case series from two tertiary care campuses of LV Prasad Eye Institute, India, between January 2011 and April 2014 was performed. Medical records of the patients presenting with DUSN (early or late stage) were reviewed.

Results

The current study included 13 patients. The majority (10/13, 76.92%) of the patients were aged 20 years or less. All patients had unilateral eye involvement. Visual acuity at presentation was 20/200 or worse in 9/13 (69.23%) patients. A delay in diagnosis occurred in 6/13 patients, and initial diagnosis in these patients included retinitis pigmentosa (4 patients) and posterior uveitis (2 patients). Clinical features included early presentation (prominent vitritis, localized retinitis, and vasculitis) in 7/13 (53.85%) patients and late presentation (attenuation of vessels, retinal pigment epithelium atrophic changes, and optic atrophy) in 6/13 (46.15%) patients. Worm could not be identified in any of the cases. All the patients received laser photocoagulation of retina and oral albendazole treatment for a period of 30 days. With treatment, visual acuity improved in seven patients (six early stage, one late stage) and remained unchanged in six patients. Mean follow-up period was 8.69 months (range, 1–21 months). The mean central foveal thickness in the affected eye, done by optical coherence tomography, during the late stage of the disease was 188.20±40 µm (range, 111–242 µm), which was significantly thinner than the fellow eye, 238.70±36.90 µm (range, 186–319 µm), P=0.008.

Conclusion

DUSN is a serious vision threatening disease, which may progress to profound vision loss in the later stage of the disease. Visualization of subretinal worm is usually not possible. Treatment with high-dose albendazole therapy and laser photocoagulation may alter the blood–retinal barrier and may be useful in achieving visual recovery.

Subretinal worm and repeat laser photocoagulation

Diffuse unilateral subacute neuroretinitis (DUSN) can be a diagnostic dilemma. Laser photocoagulation of the subretinal worm is an effective treatment for eradication. Early laser photocoagulation has been advocated. We report a case of a middle aged man who presented with decreased vision and a sub retinal macular worm that required two laser sessions for complete eradication of the worm.

Ophthalmomyiasis with a singular subretinal track

PURPOSE

To report 3 cases of myiasis with a singular subretinal track in the Northeastern part of United States.

DESIGN

Noninterventional case series.

METHODS

Three patients from Pennsylvania were referred for evaluation of a linear and serpiginous retinal scar. Funduscopic examination and fluorescein angiography were performed to assess the referred retinal lesion.

RESULTS

Funduscopic examination showed a singular subretinal track from the superior periphery to either the posterior pole or inferior midperiphery in the study cases. Fluorescein angiography showed exudative retinal detachment in all 3 cases. Laser photocoagulation of the subretinal worm was performed in all reported cases.

CONCLUSIONS

Our case series represents a report of singular subretinal tracks presumably caused by the warble fly larva in the Northeastern part of United States.