A240 BOWEL PREPARATION INDUCED MONOCULAR BLINDNESS

Abstract

Aims: The authors present an association between bowel preparation induced dehydration and acute cataract worsening. Methods: This association was identified through a clinical case encountered during routine practice. Results: A 63 year old man was seen for average risk colorectal cancer (CRC) screening. His past medical history was significant for coronary artery disease, dyslipidemia, hypertension, type 2 diabetes, benign prostatic hyperplasia, degenerative disc disease, right cataract surgery. Medications included ASA, atorvastatin, gliclazide, janumet, ramipril, indapamide, ezetimibe, insulin glargine. He had no allergies to medications. He was married, had 2 adult children, was born in Sri Lanka, worked as an auditor and was functionally independent. He was an ex-smoker, and drank 2 alcoholic beverages per night. Family history was unremarkable for gastrointestinal conditions.Colonoscopy was performed for routine CRC screening. Bowel preparation consisted of 4 liters of Go-Lytely the day prior to the procedure. His procedure was conducted as an outpatient within a tertiary care teaching hospital. The colonoscopy was uncomplicated and the examination was normal. He was discharged home and resumed his normal diet and normal medications. Shortly after the colonoscopy, the patient experienced a rapid loss of visual acuity in the left eye, which worsened over the following 48 hours. He presented to the emergency department for evaluation. A CT head was performed showing only scattered white matter changes secondary to mild microangiopathic changes, mild right maxillary fluid but no obvious cerebrovascular accident (CVA). He was referred to ophthalmology who confirmed the acuity loss (the patient was only able to count fingers) and performed fundoscopy after pupillary dilation identifying a dense white cataract. There was low clinical suspicion for giant cell arteritis, no relative afferent pupillary defect to suggest central retinal artery occlusion or central retinal vein occlusion (although fundoscopy was limited due to the cataract itself). The patient was told that that acute worsening of cataracts can occur due to dehydrationand this was likely induced by the bowel preparation. He was also seen by the general internal medicine service who felt the likelihood of CVA, given the absence of focal neurological deficits (aside from the visual acuity loss), was low. The patient underwent successful cataract excision and lens replacement 6 weeks later, with a return to normal left eye vision. Conclusions: While acute dehydration is a known risk factor for worsening of cataracts, a review of the literature did not demonstrate any reported association between colonoscopy bowel preparation, dehydration and acute cataract worsening. The product monograph for GoLytely does not list this as a potential adverse effect. This is the first case report documenting such an association.