Citation Information :
Henriquez MA, Canorio N, Maldonado C, Rincon M, Izquierdo Jr L. Snake-like Chromatin Cell Protein as an Indicator of Chronic Eye Rubbing in Patients with Keratoconus and Allergic Conjunctivitis. Int J Kerat Ect Cor Dis 2018; 7 (2):91-95.
Purpose: To evaluate the presence of snake-like chromatin (SLC) cell protein (related to eye rubbing) in patients with keratoconus or allergic conjunctivitis and in controls.
Materials and methods: Prospective experimental study included 193 eyes of 193 patients between January 2015 and July 2016; 86 had a diagnosis of new keratoconus, 88 were controls, and 19 had a diagnosis of allergic conjunctivitis and underwent impression cytology (IC). Specimens were stained with a combination of periodic acid-Schiff (PAS) and Gill\'s modified papanicolaou stains to detect the presence of SLC cell protein and morphological characterization of dry eye and allergic conjunctivitis. A questionnaire regarding eye-rubbing habits was administered.
Results: Of the patients, 56.97% (49/86 eyes) in the keratoconus group, 84.21% (16/19 eyes) in the allergy group, and 10.11% (9/89 eyes) in the control group reported rubbing their eyes. The SLC was detected in 24.41% (21/86), 73.68% (14/19), and 3.37% (3/89) of the keratoconus, allergy, and control groups respectively, who reported rubbing their eyes. In contrast, SLC was detected in 2.32% (2/86), 0% (0/19), and 1.12% (1/89) of the keratoconus, allergy, and control groups respectively, who reported not rubbing their eyes.
Conclusion: The presence of SLC cells was higher in keratoconus, allergy, and control group patients who reported rubbing their eyes. Keratoconus is independent of eye-rubbing habits and the presence of SLC cells.
Jirsova K, Juklova K, Vesela V, et al. Morphological and immunocytochemical characterization of snake-like chromatin cells. Histol Histopathol 2006;21(4):355-360.
Knop E, Reale E. Fine structure and significance of snakelike chromatin in conjunctival epithelial cells. Invest Ophthalmol Vis Sci 1994;35(2):711-719.
Ambrósio R Jr, Caiado AL, Guerra FP, et al. Novel pachymetric parameters based on corneal tomography for diagnosing keratoconus. J Refract Surg 2011;27(10):753-758.
Takamura E, Uchio E, Ebihara N, et al. Japanese guidelines for allergic conjunctival diseases 2017. Allergol Int 2017;66(2): 220-229.
Leonardi A, Bogacka E, Fauquert JL, et al. Ocular allergy: recognizing and diagnosing hypersensitivity disorders of the ocular surface. Allergy 2012;67(11):1327-1337.
Gadkari SS, Adrianwala SD, Prayag AS, et al. Conjunctival impression cytology—a study of normal conjunctiva. J Postgrad Med 1992;38(1):21-23, 22A-22B.
Karolak JA, Gambin T, Pitarque JA, et al. Variants in SKP1, PROB1, and IL17B genes at keratoconus 5q31.1-q35.3 susceptibility locus identified by whole-exome sequencing. Eur J Hum Genet 2016;25(1):73-78.
Burdon KP, Vincent AL. Insights into keratoconus from a genetic perspective. Clin Exp Optom 2013;96(2):146-154.
Lauwen S, de Jong EK, Lefeber DJ, et al. Omics biomarkers in ophthalmology. Invest Ophthalmol Vis Sci 2017;58(6): BIO88- BIO98.
Bawazeer AM, Hodge WG, Lorimer B. Atopy and keratoconus: a multivariate analysis. Br J Ophthalmol 2000; 84(8):834-836.
Sharma N, Rao K, Maharana PK, et al. Ocular allergy and keratoconus. Indian J Ophthalmol 2013;61(8):407-409.
Caputo R, Versaci F, Pucci N, et al. Very low prevalence of keratoconus in a large series of vernal keratoconjunctivitis patients. Am J Ophthalmol 2016;172:64-71.
Millodot M, Shneor E, Albou S, et al. Prevalence and associated factors of keratoconus in Jerusalem: a cross-sectional study. Ophthalmic Epidemiol 2011;18(2):91-97.
McMonnies CW, Alharbi A, Boneham GC. Epithelial responses to rubbing-related mechanical forces. Cornea 2010;29(11):1223-1231.
Chervenkoff JV, Hawkes E, Ortiz G, et al. A randomized, fellow eye, comparison of keratometry, aberrometry, tear film, axial length and the anterior chamber depth after eye rubbing in non-keratoconic eyes. Eye Vis (Lond) 2017;4:19.
Marner K. ‘Snake-like’ appearance of nuclear chromatin in conjunctival epithelial cells from patients with keratoconjunctivitis sicca. Acta Ophthalmol (Copenh) 1980;58(5): 849-853.
Pienaar JG, Price HM. Ultrastructure and origin of the Anitschkow cell. Am J Pathol 1967;51(6):1063-1091.
McMonnies CW. Mechanisms of rubbing-related corneal trauma in keratoconus. Cornea 2009;28(6):607-615.
Galvis V, Sherwin T, Tello A, et al. Keratoconus: an inflammatory disorder? Eye (Lond) 2015;29(7):843-859.