Optic neuritis with secondary retinal venous stasis in a case of abdominal tuberculosis.

The authors report a case of unilateral optic neuritis along with secondary retinal venous stasis in a patient diagnosed with abdominal tuberculosis. Patient presented with diminished visual acuity, colour perception and Marcus Gunn pupillary response, pointing towards optic nerve involvement. Associated findings of disc edema, dilated and tortuous veins, along with hemorrhages on disc and superotemporal quadrant made diagnosis of retinal venous stasis secondary to optic neuritis imperative. The visual outcome of the patient paralleled that expected with optic neuritis. The authors believe that impairment of retinal venous outflow secondary to optic neuritis is a distinct but a rare presentation.

Introduction

Retinal vein occlusion (RVO) is second only to diabetic retinopathy as the most frequently encountered disorder of retinal vasculature. The condition is a result of a blend of three general changes at the level of ocular vessels, referred to as Virchow's triad: venous stasis, degenerative changes of the vessel wall and blood hypercoagulability. Pathomechanism of RVO in young adults is usually contributed by atypical factors like acquired and inherited coagulation disorders, myeloproliferative disorders, infectious and occlusive peri-phlebitis and sometimes optic nerve inflammation. We report a unique case of impending retinal venous stasis in a patient with sudden painless progressive vision loss due to optic neuritis secondary to abdominal tuberculosis.

Case Report

An 18-year-old male presented with rapidly progressive painless diminution of vision in the left eye for 10 days along with evening rise of temperature, abdominal discomfort, and loss of appetite for 1 month. Snellen's acuity of 6/6 (OD) and 3/60 (OS) was recorded. The patient had a defective red-green color vision in the left eye and relative afferent pupillary defect (RAPD). Fundus examination showed edematous disc with peripapillary dilated and tortuous vessels and venous sheathing in all four quadrants extending up to mid-periphery [Figure 1]. Macular edema was noted. Flame-shaped hemorrhages were seen surrounding vessels in superotemporal quadrant [Figure 2]. The right eye fundus was unremarkable. The patient had a 3 cm × 3 cm palpable lymph node in the right supraclavicular area. No other systemic anomalies were detected.

Figure 1

Fundus photograph of OS showing disc edema, single disc hemorrhage at superior border of disc, and dilated and tortuous veins with sheathing around the disc and a dull foveal reflex

Figure 2

Fundus photograph of superotemporal quadrant with superficial hemorrhages and venous sheathing

Fluorescein angiography revealed blocked fluorescence corresponding to superficial hemorrhages and increasing hyperfluorescence around veins extending from disc to mid-periphery of the left eye with late leakage [Figures 3 and 4]. Abdominal ultrasound showed multiple enlarged lymph nodes in the retrocaval region of right renal hilum and in mesentery. Fine-needle aspiration cytology from the right cervical lymph node showed necrosis with degenerated acute and chronic inflammatory cells, and Ziehl–Neelsen stain was positive for acid-fast bacilli. Chest X-ray was normal, and Mantoux test was positive (13 mm × 12 mm).

Figure 3

Fundus florescein angiography image showing blocked fluorescence due to superficial hemorrhages along the dilated and tortuous veins

Figure 4

Late arteriovenous phase image showing diffuse leakage from vessels around the disc and in the arcade vessels

The patient was started on antitubercular therapy with oral steroids. At 1 month, fundus showed a partial macular star [Figure 5]. At 3 months, the patient had visual acuity of 6/24 with resolution of the macular star.

Figure 5

Posttreatment fundus photograph showing resolved disc edema

Discussion

When we look out for possible differentials for disc edema, a number of factors need to be considered. Laterality, presence of abnormal pupil response, field defects, and color vision defects are the major findings that can help us narrow down our diagnosis to entities such as papillophlebitis, optic neuritis, or anterior ischemic optic neuropathy which can predispose to retinal venous stasis.[1] Fundus signs such as peripapillary edema, venous tortuosity, and fluorescein angiography patterns can significantly contribute to the diagnosis of optic neuritis. Duker et al. reported five cases of optic neuritis with secondary retinal venous stasis which had similar appearance to papillophlebitis on ophthalmoscopic examination.[2] Mughaddasifar et al. have also reported a case with papillophlebitis secondary to tuberculosis with no other systemic involvement.[3] Because of the similar fundus appearance, this variant of optic neuritis may be confused with either papillitis or central retinal venous occlusion in young patients. We suggest that in young patients presenting with unilateral loss of visual acuity, color vision, RAPD, and characteristic retinal venous-stasis picture, the possibility of an inflammatory pathology affecting optic nerve head inflammation leading to retinal vein occlusion or vice versa should be kept in mind and the patient should be investigated for the same.

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Conflicts of interest

There are no conflicts of interest.