10 yo healthy boy with vision loss OS.
Beginning 5 days prior to onset he noticed intermittent bright stars in vision. On day of presentation he developed blurry (not dark) vision while playing soccer on a hot day, stopped playing, got a little better, resumed playing and at end of game vision was dark OS. Maybe a little sore when he moved his left eye while playing soccer, but not otherwise. No diplopia, no headache.
No recent illnesses, except for 2-3 episodes of severe abdominal pain in the 2.5 months preceding presentation that would awaken him from sleep, but better by morning. Otherwise ROS negative. Does not eat a lot but eats a relatively healthy diet. No recent travel, no family history of vision problems. He has an outdoor cat and is active outdoors, was playing outside after storms about a month ago, but did not ingest any dirty water.
Vision 20/20 OD, HM OS. 3-4+ RAPD OS. Fundus examination OD normal; OS showed very mild optic nerve edema inferiorly and superiorly, macula notably pale – looked like a CRAO – but vessels unremarkable (no tortuosity, no unusual caliber, no signs of embolus nor vasculitis).
MRI showed mild edema of and around optic nerve where it enters globe, mild enhancement of tissue posterior to sclera and superior to optic nerve, no enhancement of nerve itself.
IVMP 30mg/kg/day was started about 24 hours after initial presentation with no improvement in vision. IVIg was then started with no improvement in vision.
All tests of serum and CSF to date have been negative: ESR, CRP, CBC (normal diff), ANA, ACE, ANCA, MOG, NMO, syphilis, quant gold, B12/folate, COVID PCR, Bartonella IgG and IgM, leptospira, CSF protein/glucose/cx/meningitis panel/NMO/MOG/toxo
Hypercoag panel pending
Only abnormal tests are slightly low serum and CSF IGG
Repeat MRI showed stable edema of nerve, interval decrease in enhancement adjacent to nerve
Any thoughts regarding etiology or further testing would be greatly appreciated!