This study investigated the morphological characteristics of corneal microstructure in the quiescent phase of vernal keratoconjunctivitis (VKC).
Methods
Twenty patients with quiescent VKC and 25 healthy subjects were included. In vivo confocal microscopy (IVCM) of the central cornea was performed. Cellular density of each layer and the morphology of subbasal nerve plexus (SBNP) was analysed. Langerhans cell density (LCD), morphology (LCM), and field area (LCF) were also examined.
Results
No differences were found either in cell densities nor in SBNP morphology (p > 0.05). LCD, LCM and LCF were significantly higher in the VKC group (p = 0.005, p < 0.001 and p < 0.001, respectively). The severity of papillary hypertrophy had a significant impact on LCD, LCM and LCF (β-coefficient: 19.541, p < 0.001; β-coefficient: 0.283, p < 0.001 and β-coefficient: 595.255, p < 0.001, respectively).
Discussion
In quiescent VKC, LCD, LCM, and LCF were increased, and they were associated with the severity of papillary hypertrophy. Alterations of Langerhans cells indicate a subclinical inflammatory process without ocular symptoms.
BieloryL. Allergic and immunologic disorders of the eye. Part I: immunology of the eye. J Allergy Clin Immunol2000; 106: 805–816.
3.
VichyanondPPacharnPPleyerU,et al.Vernal keratoconjunctivitis: a severe allergic eye disease with remodeling changes. Pediatr Allergy Immunol2014; 25: 314–322.
4.
Al-AkilySABamashmusMA. Ocular complications of severe vernal keratoconjunctivitis (VKC) in Yemen. Saudi J Ophthalmol2011; 25: 291–294.
5.
LeonardiABogackaEFauquertJL, et al.Ocular allergy: recognizing and diagnosing hypersensitivity disorders of the ocular surface. Allergy2012; 67: 1327–1337.
6.
LeonardiA. Management of vernal keratoconjunctivitis. Ophthalmol Ther2013; 2: 73–88.
BoniniSBoniniSLambiaseA, et al.Vernal keratoconjunctivitis revisited: a case series of 195 patients with long-term followup. Ophthalmology2000; 107: 1157–1163.
9.
Bremond-GignacDDonadieuJLeonardiA, et al.Prevalence of vernal keratoconjunctivitis: a rare disease?Br J Ophthalmol2008; 92: 1097–1102.
10.
ArifASAaqilBSiddiquiA,et al.Corneal complications and visual impairment in vernal keratoconjunctivitis patients. J Ayub Med Coll Abbottabad2017; 29: 58–60.
11.
NebbiosoMZicariAMLollobrigidaV,et al.Assessment of corneal alterations by confocal microscopy in vernal keratoconjunctivitis. Semin Ophthalmol2015; 30: 40–43.
12.
LeQHHongJXZhuWQ,et al.[Morphological characteristics of cornea in patients with vernal keratoconjunctivitis by in vivo laser scanning confocal microscopy]. Zhonghua Yan Ke Za Zhi2011; 47: 416–422.
13.
ChanTCYWongESChanJCK, et al.Corneal backward scattering and higher-order aberrations in children with vernal keratoconjunctivitis and normal topography. Acta Ophthalmol2018; 96: e327–ee33.
14.
VillaniEDello StrologoMPichiF, et al.Dry eye in vernal keratoconjunctivitis: a cross-sectional comparative study. Medicine (Baltimore)2015; 94: e1648.
15.
MiceraADi ZazzoAEspositoG,et al.Quiescent and active tear protein profiles to predict vernal keratoconjunctivitis reactivation. Biomed Res Int2016; 2016: 9672082.
16.
LiuMGaoHWangT,et al.An essential role for dendritic cells in vernal keratoconjunctivitis: analysis by laser scanning confocal microscopy. Clin Exp Allergy2014; 44: 362–370.
17.
LeonardiALazzariniDBortolottiM,et al.Corneal confocal microscopy in patients with vernal keratoconjunctivitis. Ophthalmology2012; 119: 509–515.
18.
ModugnoRLScaloraTBonaldoA,et al.Corneal microstructural changes by confocal microscopy in vernal keratoconjunctivitis patients treated with topical cyclosporine. Ocul Immunol Inflamm2021; 29: 1599–1605.
19.
DehghaniCPritchardNEdwardsK,et al.Fully automated, semiautomated, and manual morphometric analysis of corneal subbasal nerve plexus in individuals with and without diabetes. Cornea2014; 33: 696–702.
20.
Oliveira-SotoLEfronN. Morphology of corneal nerves using confocal microscopy. Cornea2001; 20: 374–384.
21.
ZhivovAStaveJVollmarB,et al.In vivo confocal microscopic evaluation of Langerhans cell density and distribution in the normal human corneal epithelium. Graefes Arch Clin Exp Ophthalmol2005; 243: 1056–1061.
22.
MarsovszkyLNemethJReschMD, et al.Corneal Langerhans cell and dry eye examinations in ankylosing spondylitis. Innate Immun2014; 20: 471–477.
23.
ReschMDMarsovszkyLNemethJ,et al.Dry eye and corneal langerhans cells in systemic lupus erythematosus. J Ophthalmol2015; 2015: 543835.
24.
MarsovszkyLReschMDNemethJ, et al.In vivo confocal microscopic evaluation of corneal Langerhans cell density, and distribution and evaluation of dry eye in rheumatoid arthritis. Innate Immun2013; 19: 348–354.
25.
DehghaniCFrostSJayasenaR, et al.Morphometric changes to corneal dendritic cells in individuals with mild cognitive impairment. Front Neurosci2020; 14: 556137.
26.
KheirkhahARahimi DarabadRCruzatA, et al.Corneal epithelial immune dendritic cell alterations in subtypes of dry eye disease: a pilot in vivo confocal microscopic study. Invest Ophthalmol Vis Sci2015; 56: 7179–7185.
27.
ReschMDImreLTapasztoB,et al.Confocal microscopic evidence of increased Langerhans cell activity after corneal metal foreign body removal. Eur J Ophthalmol2008; 18: 703–707.
28.
GuthoffRFBCSJ. Atlas of confocal laser scanning in-vivo microscopy in ophthalmology. Springer-Verlag Berlin Heidelberg: SPRINGER, 2016.
29.
YilmazYCIpekSCOzerMD. Corneal and lens densitometry in patients with vernal keratoconjunctivitis. Int Ophthalmol2021; 41: 2667–2676.
30.
SmithREReyesNJKhandelwalP, et al.Secondary allergic T cell responses are regulated by dendritic cell-derived thrombospondin-1 in the setting of allergic eye disease. J Leukoc Biol2016; 100: 371–380.
PatelDVZhangJMcGheeCN. In vivo confocal microscopy of the inflamed anterior segment: a review of clinical and research applications. Clin Exp Ophthalmol2019; 47: 334–345.
33.
MastropasquaLNubileMLanziniM, et al.Epithelial dendritic cell distribution in normal and inflamed human cornea: in vivo confocal microscopy study. Am J Ophthalmol2006; 142: 736–744.
34.
HamrahPHuqSOLiuY, et al.Corneal immunity is mediated by heterogeneous population of antigen-presenting cells. J Leukoc Biol2003; 74: 172–178.
35.
ZhivovAStaveJVollmarB,et al.In vivo confocal microscopic evaluation of langerhans cell density and distribution in the corneal epithelium of healthy volunteers and contact lens wearers. Cornea2007; 26: 47–54.
36.
MassingaleMLLiXVallabhajosyulaM,et al.Analysis of inflammatory cytokines in the tears of dry eye patients. Cornea2009; 28: 1023–1027.
37.
DanaR. Comparison of topical interleukin-1 vs tumor necrosis factor-alpha blockade with corticosteroid therapy on murine corneal inflammation, neovascularization, and transplant survival (an American Ophthalmological Society thesis). Trans Am Ophthalmol Soc2007; 105: 330–343.
38.
ChigbuDILabibBA. Immunopharmacology in vernal keratoconjunctivitis: current and future perspectives. Pharmaceuticals (Basel)2021; 14: 658.
