Evaluation of Tear Film Urea Level as a Diagnostic Marker of Dry Eye Disease: A Pilot Study

Abstract Introduction Urea secreted in the sweat is important for skin moisture. Similarly, ocular surface moisture is maintained by the conjunctiva. Based on this, the level of urea in tear film can be used as a potential diagnostic test for dry eye disease (DED). One of the standard tests for DED is Schirmer's test (ST). The aim of this study was to compare tear film urea to values of ST. Methods Fifty patients symptomatic for DED having ST ≤ 10 mm/5 min were enrolled in the study. Fifty age- and sex-matched asymptomatic subjects with ST > 10 mm/5 min were taken as controls. All patients were subjected to an estimation of tear film urea, collected using micropipettes, and analyzed by an Erba Chem 5 semi-autoanalyzer. Based on the ST reading as per the Dry Eye Workshop 2007 (DEWS) classification, dry eye was classified as dry eye (≤ 10 mm/5 min), severe dry eye (≤ 5 mm/5 min), and very severe dry eye (≤ 2 mm/5 min). Tear film urea values were compared with ST values that were considered standard. Statistical analysis was done using Medcalc version 19.7. A p-value ≤ 0.05 was considered significant. Results The mean tear film urea levels in cases were (26.78 ± 5.70 mg/dL) significantly lower compared with controls (41.72 ± 6.86 mg/dL). The area under the receiver characteristic operator curve (AUC) for tear film urea in diagnosing DED was 0.936 (p < 0.0001) with a cutoff of ≤ 37.2 mg/dL, yielding a sensitivity of 96% and a specificity of 76%. For diagnosing severe DED, the AUC for tear film urea was 0.824 (p < 0.0001) with a cutoff value of ≤ 23.4 mg/dL, yielding a sensitivity of 60.8% and a specificity of 92.59%. For diagnosis of very severe DED, the AUC for tear film urea was 0.972 (p < 0.0001) with a cutoff value of ≤ 19.8 mg/dL, yielding a sensitivity of 100% and a specificity of 93.62%. On comparing ST values to tear film urea, the regression coefficient was 0.85 (p < 0.0001), suggesting a linear relationship between ST and tear film urea. Conclusion The study demonstrates that tear film urea can be a potential diagnostic marker for DED. The study also indicates that tear film urea level is linearly related to Schirmer's test values and provides an approximate diagnostic cutoff level for the design of future large-scale studies.

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Comparison of Clinical Use of Ocular-surface Disease Index Questionnaire, Tear Film Break-up time, and Schirmer Tests in Diagnosing Dry-eye

Ophthalmology Research An International Journal ◽

10.9734/or/2019/v11i230125 ◽

2019 ◽

pp. 1-7

Author(s):

Suwarna Suman ◽

Prachi Goyal

Keyword(s):

Dry Eye ◽

Ocular Surface ◽

Tear Film ◽

Dry Eye Disease ◽

Disease Index ◽

Ocular Surface Disease ◽

Eye Disease ◽

Ocular Surface Disease Index ◽

Schirmer’S Test ◽

The Mean

Aims: To evaluate and compare the diagnostic values and clinical utility of the Ocular Surface Disease Index (OSDI) questionnaire, the tear film break-up time test (TBUT), and the Schirmer’s test in diagnosing dry eye disease in patients presenting with dry eye symptoms. Study Design: A prospective observational study. Place and Duration of Study: Department of Ophthalmology, AIIMS Jodhpur, Rajasthan, India. Two-month period between July 2016 and September 2016. Methodology: We have included 100 patients aged >20 years having foreign body sensations, burning sensations, pain, dryness, blurred vision, photophobia, redness in the study. Routine ophthalmological examination was performed after OSDI questionnaire, followed by TBUT and Schirmer’s test and outcomes were evaluated. Results: The mean age of 100 participants was 43 ± 15.97years (range 20–78 years). The mean OSDI, TBUT, and Schirmer’s test scores were 58.67± 12.12 (range 30.0–88.9), 5.77 ± 3.49 seconds (range 0–17 seconds), and 09.78 ± 7.93 mm (range 0–32.5 mm), respectively. There was a statistically highly significant inverse correlation between the OSDI and TBUT (r = −0.597, P = <0.0001), statistically significant correlation between TBUT and Schirmer test (r= -0.227, p= 0.023), whereas no significant correlation noted between the OSDI and Schirmer’s test (r= -0.142, p= 0.158). Conclusion: The prevalence of dry eye disease (DED) is increasing these days. For early recognition and treatment, we need rapid, reliable and less invasive diagnostic test in daily practice. The OSDI together with the TBUT is less time consuming, easy to perform and can be useful in diagnosis of DED.

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Tear Proteomics Study of Dry Eye Disease: Which Eye Do You Adopt as the Representative Eye for the Study?

International Journal of Molecular Sciences ◽

10.3390/ijms22010422 ◽

2021 ◽

Vol 22 (1) ◽

pp. 422

Author(s):

Ming-Tse Kuo ◽

Po-Chiung Fang ◽

Shu-Fang Kuo ◽

Alexander Chen ◽

Yu-Ting Huang

Keyword(s):

Dry Eye ◽

Ocular Surface ◽

Tear Film ◽

Dry Eye Disease ◽

Eye Disease ◽

Mechanistic Studies ◽

Clinical Tests ◽

Tear Proteins ◽

Proteomic Data ◽

Surface Performance

Most studies about dry eye disease (DED) chose unilateral eye for investigation and drew conclusions based on monocular results, whereas most studies involving tear proteomics were based on the results of pooling tears from a group of DED patients. Patients with DED were consecutively enrolled for binocular clinical tests, tear biochemical markers of DED, and tear proteome. We found that bilateral eyes of DED patients may have similar but different ocular surface performance and tear proteome. Most ocular surface homeostatic markers and tear biomarkers were not significantly different in the bilateral eyes of DED subjects, and most clinical parameters and tear biomarkers were correlated significantly between bilateral eyes. However, discrepant binocular presentation in the markers of ocular surface homeostasis and the associations with tear proteins suggested that one eye’s performance cannot represent that of the other eye or both eyes. Therefore, in studies for elucidating tear film homeostasis of DED, we may lose some important messages hidden in the fellow eye if we collected clinical and proteomic data only from a unilateral eye. For mechanistic studies, it is recommended that researchers collect tear samples from the eye with more severe DED under sensitive criteria for identifying the more severe eye and evaluating the tear biochemical and proteomic markers with binocular concordance drawn in prior binocular studies.

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A comparative assessment of dry eye disease among outdoor street sweepers and indoor office cleaners

BMC Ophthalmology ◽

10.1186/s12886-021-02025-y ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Chigozie I. Echieh ◽

Bassey A. Etim ◽

Chidiebere Peter Echieh ◽

Taiwo Oyeniyi ◽

Jeff Ajewole

Keyword(s):

Dry Eye ◽

Cross Sectional Study ◽

Dry Eye Disease ◽

Eye Disease ◽

Ocular Surface Disease Index ◽

Simultaneous Exposure ◽

Cross Sectional ◽

Systematic Random Sampling ◽

Schirmer’S Test ◽

Multi Stage

Abstract Background Occupational predisposition to dry eye disease is known. Simultaneous exposure to multiple factors may pose more risk. Street sweepers are exposed to sunlight in addition to dust which all sweepers are exposed to. Tropical climate predisposes to significant exposure to sunlight. Combined exposure to dust and sunlight may lead to a synergy of factors. This study aims to assess the prevalence of dry eye disease (DED) amongst Street sweepers and Office cleaners in Calabar metropolis. Methods A cross-sectional study was conducted among street sweepers and office cleaners. A systematic random sampling and multi-stage sampling method were used to select street sweepers (n = 115) and office cleaners (n = 115) respectively for the study. A pretested semi-structured interviewer-administered questionnaire was used to obtain information after which the respondents had an ophthalmic examination. An assessment of DED was done with Ocular Surface Disease Index (OSDI) questionnaire, Schirmer’s test, and tear break up time (TBUT). OSDI scores of 33 and above; Schirmer’s test readings of < 10 mm wetting in 5 min and a TBUT of less than 10s in either eye were considered as positive dry eye disease. Results The majority of respondents were females 215(93.5%) compared to males 15 (6.5%). The overall mean age of respondents was 40.96 ± 9.8 years. The average OSDI score, Schirmer’s test as well as TBUT among participants was 26.4 ± 16.0, 16.44 ± 9.52 mm, and 12.38 ± 4.53 s respectively. The prevalence of DED among Street sweepers was 35.7% compared to 20% among office cleaners using the OSDI questionnaire (p = 0.352). The prevalence of DED among street sweepers was 32.2% compared to 30.4% among Office cleaners using the Schirmer’s test. (p = 0.73) The TBUT reported a prevalence of 38.3% of DED among Street sweepers compared to 32.2% in office cleaners. (p = 0.48) Overall; the prevalence of dry eye disease among Street sweepers and office cleaners using OSDI score, Schirmers test, as well as TBUT were not statistically significant (> 0.05) Street Sweepers had higher odds of developing dry eye disease compared to office cleaners (OR = 2.085; C.I. =1.106–3.929; p = 0.02). Negative correlation coefficient was observed between TBUT and OSDI (rs = − 0.102; p = 0.125). This was not statistically significant. Conclusion Street sweepers had a higher prevalence of dry eye disease compared to office cleaners due to a higher risk of increased exposure to environmental factors such as dust, smoke, and sunlight. This effect is possibly due to a synergy of factors. Studies on dose-response are warranted.

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A distinct cytokines profile in tear film of dry eye disease (DED) patients with HIV infection

Cytokine ◽

10.1016/j.cyto.2016.08.026 ◽

2016 ◽

Vol 88 ◽

pp. 77-84 ◽

Cited By ~ 12

Author(s):

Rupesh Agrawal ◽

Praveen Kumar Balne ◽

Anuradha Veerappan ◽

Veonice Bijin Au ◽

Bernett Lee ◽

...

Keyword(s):

Hiv Infection ◽

Dry Eye ◽

Tear Film ◽

Dry Eye Disease ◽

Eye Disease

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Cationic Thiolated Poly(aspartamide) Polymer as a Potential Excipient for Artificial Tear Formulations

Journal of Ophthalmology ◽

10.1155/2016/2647264 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Mária Budai-Szűcs ◽

Gabriella Horvát ◽

Barnabás Áron Szilágyi ◽

Benjámin Gyarmati ◽

András Szilágyi ◽

...

Keyword(s):

Dry Eye ◽

Tear Film ◽

Dry Eye Disease ◽

Eye Disease ◽

Eye Drops ◽

Thiol Groups ◽

Physiological Properties ◽

Disulphide Bond Formation ◽

Polymer Bearing

Dry eye disease is a relatively common ocular problem, which causes eye discomfort and visual disorders leading to a decrease in the quality of life. The aim of this study was to find a possible excipient for eye drop formulations, which is able to stabilize the tear film. A cationic thiolated polyaspartamide polymer, poly[(N-mercaptoethylaspartamide)-co-(N-(N′,N′-dimethylaminoethyl)aspartamide)] (ThioPASP-DME), was used as a potential vehicle. Besides satisfying the basic requirements, the chemical structure of ThioPASP-DME is similar to those of ocular mucins as it is a protein-like polymer bearing a considerable number of thiol groups. The solution of the polymer is therefore able to mimic the physiological properties of the mucins and it can interact with the mucus layer via disulphide bond formation. The resultant mucoadhesion provides a prolonged residence time and ensures protective effect for the corneal/conjunctival epithelium. ThioPASP-DME also has an antioxidant effect due to the presence of the thiol groups. The applicability of ThioPASP-DME as a potential excipient in eye drops was determined by means of ocular compatibility tests and through examinations of the interactions with the mucosal surface. The results indicate that ThioPASP-DME can serve as a potential eye drop excipient for the therapy of dry eye disease.

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Tear film osmolarity and dry eye disease: a review of the literature

Clinical Ophthalmology ◽

10.2147/opth.s95242 ◽

2015 ◽

pp. 2039 ◽

Cited By ~ 49

Author(s):

Richard Potvin ◽

Sarah Makari ◽

Christopher Rapuano

Keyword(s):

Dry Eye ◽

Tear Film ◽

Dry Eye Disease ◽

Eye Disease ◽

Review Of The Literature

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Evaluation of Objective Signs and Subjective Symptoms of Dry Eye Disease in Patients with Inflammatory Bowel Disease

BioMed Research International ◽

10.1155/2019/8310583 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Zsolt Barta ◽

Levente Czompa ◽

Aniko Rentka ◽

Eva Zold ◽

Judit Remenyik ◽

...

Keyword(s):

Inflammatory Bowel Disease ◽

Dry Eye ◽

Bowel Disease ◽

Clinical Signs ◽

Tear Film ◽

Dry Eye Disease ◽

Eye Disease ◽

Subjective Symptoms ◽

Ocular Surface Disease Index ◽

Inflammatory Bowel

Aim. To evaluate tear film parameters and relationship of objective clinical signs and subjective symptoms of dry eye disease (DED) in inflammatory bowel disease (IBD) subgroups. Methods. 39 patients with Crohn’s disease (CD), 26 patients with ulcerative colitis (UC), and 39 control persons with no ocular symptoms or surface disorders were included in this prospective, case-control, and cross-sectional study. The ocular surface disease index (OSDI) questionnaire was applied to evaluate dry eye symptoms, and objective tests of DED were performed on both eyes of each subject. Results. The average of OSDI scores was 30.59 (±16.68) in CD patients, 24.67 (±23.48) in UC patients, and 11.19 (±5.8) in controls. Except for tear film breakup time (tBUT) and Schirmer-I values other objective parameters were better in UC patients, than in CD patients. CD patients rather than UC patients tend to develop DED. This was associated with immunosuppressant and TNF-α inhibitor use. Conclusions. Clinicians must be aware of the spectrum of DED involvement in IBD and suggest using artificial tears in order to decrease severity of ocular complications.

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Normalized ocular surface temperature models for tear film characteristics and dry eye disease evaluation

The Ocular Surface ◽

10.1016/j.jtos.2020.04.002 ◽

2020 ◽

Author(s):

Tai-Yuan Su ◽

Shu-Wen Chang

Keyword(s):

Surface Temperature ◽

Dry Eye ◽

Ocular Surface ◽

Tear Film ◽

Dry Eye Disease ◽

Eye Disease ◽

Film Characteristics

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The Association between Tear Film Thickness as Measured with OCT and Symptoms and Signs of Dry Eye Disease: A Pooled Analysis of 6 Clinical Trials

Journal of Clinical Medicine ◽

10.3390/jcm9113791 ◽

2020 ◽

Vol 9 (11) ◽

pp. 3791

Author(s):

Gerhard Garhöfer ◽

Valentin Aranha Dos Santos ◽

Hannes Stegmann ◽

Doreen Schmidl ◽

Narine Adzhemian ◽

...

Keyword(s):

Clinical Trials ◽

Film Thickness ◽

Dry Eye ◽

Tear Film ◽

Pooled Analysis ◽

Dry Eye Disease ◽

Eye Disease ◽

Break Up ◽

Symptoms And Signs ◽

Schirmer I Test

Purpose: To determine the association between tear film thickness (TFT) as measured with ultra-high resolution optical coherence tomography (UHR-OCT) and signs and symptoms of dry eye disease (DED). Methods: A total of 450 eyes from 225 patients with DED from six different randomized clinical trials were included in this pooled analysis. In all subjects, TFT was measured with a custom-built UHR-OCT system. Symptoms of DED were quantified using a standardized Ocular Surface Disease Index (OSD)I questionnaire and clinical signs including tear film break up time (TFBUT) and Schirmer I test were assessed. Associations of the average TFT with OSDI, TFBUT, and Schirmer I test were calculated using a linear regression analysis. Results: The average TFT of the included sample (mean age, 45.0 ± 13.3 years; 65% female) was 4.2 ± 0.5 µm and the OSDI 36.2 ± 10.4. A significant negative correlation was found between TFT and OSDI (r = −0.36 to −0.31; p < 0.001). Tear break up time and Schirmer I test were not correlated with OSDI. Significant albeit weak correlations were found between TFT and TFBUT (r = 0.17 to 0.25; p < 0.01) as well as Schirmer I (r = 0.36 to 0.37; p < 0.001). Subgroup analysis revealed that the correlation was stronger in the subjects with abnormal Schirmer I (<15 mm; r = 0.50 to 0.54; p < 0.001). Conclusions: The present study demonstrates an objective measurement of TFT using a novel OCT approach for DED that correlates with symptoms and signs of DED. Our data are consistent with the idea that TFT represents the aqueous-deficient component of DED.

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