Corneal Fluorescein Staining Distinguishes Dry Eye, Pediatric Blepharokeratoconjunctivitis

Personal perspective of ophthalmologist ready to examine the eye of a sad, young female patient whose eye is teary and bloodshot from an eye irritation. Real injury and examination. The patient rests her chin and forehead in a slit lamp instrument for closer examination.
No statistically significant differences were observed in any other test between the patients with BKC and controls.

Blepharokeratoconjunctivitis (BKC) represents up to a quarter of all referrals for pediatric corneal consults, and dry eye is a familiar concern, but there is a lack of diagnostic test cut-off benchmarks established for dry eye disease (DED) in children — particularly in the literature pertaining to those with BKC, according to a pilot study published in the Canadian Journal of Ophthalmology. This analysis is the first to examine DED signs and symptoms in children with controlled BKC, according to researchers.

A subjective questionnaire and 5 objective tests were employed in the prospective case-controlled observation that examined dry eye in children with and without BKC. Consecutive study participants with previously moderate, but stabilized BKC, and healthy control participants were recruited. Participants between ages 6 and 18 years visited the Ophthalmology Clinic at the Hospital for Sick Children in Toronto, from March 2015 to December 2015. 

Of 22 eyes (11 patients) in the BKC group, and 28 eyes (14 patients) in the control set, mean Canadian Dry Eye Assessment (CDEA) survey scores did not significantly differ between cohorts (P =.16). CDEA is a symptom-oriented questionnaire based on the Ocular Surface Disease Index (OSDI). In addition, both groups displayed comparable rates of asymptomatic or mildly symptomatic DED (both P =.35), and there were no symptoms expressed to indicate moderate or severe DED.

Importantly, significantly greater mean corneal fluorescein staining (CFS) scores were exhibited in children with BKC in either the worse eye (P =.04) or in all eyes (P =.01), compared with controls. Conversely, there resulted no significant differences between cohorts in scores of other objective tests, including mean maximum tear osmolarity, inter-eye variability of tear osmolarity, Schirmer’s tear test 1, tear film break-up time, and conjunctival lissamine green staining score. SICCA OSS mean scores were also similar (P =.51). 

Investigators looked at relationships among symptoms and signs, and correlations emerged in both groups between CDEA and CFS scores; nearing significance in children with BKC (P =.07) and attaining significance in controls (P =.03). Also, mean CDEA was compared for patients meeting cut-offs for DED in objective tests. According to the data, “in patients with BKC, DED diagnosed using a corneal fluorescein score ≥1 had a statistically higher CDEA score than those who did not meet the criteria,” (P =.03). 

The study observes that both cohorts showed comparable Schirmer’s tear tests; thus corneal findings, including greater CFS in children with BKC may have been due to subclinical inflammation, rather than decreased moisture. Notably, there are no currently authorized DED subjective surveys for children, which may affect answers in questionnaires initially worded for adult understanding.

In the 2 study groups, mean age and female-male ratio were similar. Limitations of the study included its cross-sectional design, variable test results in the BKC set, and no use of meibography. The sample was small — although the difference in CFS between cohorts was significant. “Corneal fluorescein staining may be a useful diagnostic test that best correlates with symptoms in this patient group (BKC),” the study explains.


Elbaz U, Tone SO, Fung SSM, et al. Evaluation of dry eye disease in children with blepharokeratoconjunctivitisCan J Ophthalmol. Published online March 16, 2021.