Diagnostic Challenges Of Ocular Symptoms Related To Vitamin A Deficiency Following Bariatric Surgery

The aim is to present a patient with xerophthalmia (dryness of conjunctiva and cornea) and nyctalopia (night blindness) due to vitamin A deficiency (VAD) associated with bariatric (weight loss) surgery.

This case report describes a 60-year-old male patient who presented with an acute onset of nyctalopia three weeks prior to the ophthalmological examination at University Hospital Centre Zagreb. The patient also reported symptoms of dry eye such as irritation and burning. He had undergone partial gastric and small bowel resection as part of bariatric surgery eight years ago and had been taking oral vitamin supplements irregularly since then. 

The examination included best corrected visual acuity (BCVA), Ishihara color test, pupil function, ocular motility, confrontation field test, and slit-lamp examination. Objective dry eye signs were assessed by noting TBUT (tear break-up time), fluorescein corneal and conjunctival staining according to the NEI (National Eye Institute) scale, and LIPCOF (lid-parallel conjunctival folds). Further examination included Goldmann applanation tonometry, fundoscopic exam, photo-fundus, full-field electroretinography (ERG), optical coherence tomography (OCT), visual evoked potentials (VEP), Octopus and Goldmann perimetry, and laboratory workup.

Slit-lamp examination showed conjunctival deposits along the corneal limbus at 3 o’clock in both eyes, which appeared to be Bitot’s spots. TBUT was 3/3 seconds, fluorescein corneal staining was 4/2 with diffuse small dotted staining. Full-field ERG showed extinguished scotopic responses in both eyes. OCT showed attenuation of photoreceptor ellipsoid zone (EZ). Laboratory workup confirmed VAD (41.9 µg/L). Control examination four months after initiation of oral vitamin A supplementation and use of artificial tears showed no signs of dry eye (TBUT was 5+ seconds, corneal staining was 0/0, and there were no Bitot’s spots), ERG scotopic responses were normal, photoreceptors EZ was visible on OCT, and vitamin A levels in serum were normal.

Bariatric surgery-induced VAD due to inadequate vitamin A supplementation may present a significant diagnostic challenge. At the same time, it can lead to severe conditions such as keratomalacia and corneal perforation or complete loss of vision. This case highlights the importance of considering VAD in the differential diagnosis of post-bariatric surgery patients presenting with xerophthalmia and nyctalopia.