Stachon Tanja, Stachon Axel, Hartmann Ulrike, Seitz Berthold, Langenbucher Achim, Szentmáry Nóra
a Department of Ophthalmology , Saarland University Medical Center , Homburg/Saar , Germany.
b Westpfalz-Klinikum GmbH, Institute for Laboratory Medicine , Kaiserslautern , Germany.
Curr Eye Res. 2017 Jun;42(6):842-846. doi: 10.1080/02713683.2016.1256413. Epub 2017 Jan 13.
Keratoconus is a noninflammatory disease of the cornea associated with progressive thinning and conical shape. Metabolic alterations in the urea cycle, with changes in collagen fibril stability, oxidative stress, thyroid hormones and prolactin with regulatory effect on biosynthesis and biomechanical stability of corneal stroma, may all play a role in keratoconus etiology. Our purpose was to determine urea, uric acid, prolactin and free thyroxin (fT4) concentrations in human aqueous humor (hAH) of keratoconus and cataract patients.
hAH was collected from 100 keratoconus (penetrating keratoplasty) (41.9 ± 14.9 years, 69 males) and 100 cataract patients (cataract surgery) (71.2 ± 12.4 years, 58 males). Urea, uric acid, prolactin and fT4 concentrations were measured by Siemens clinical chemistry or immunoassay system. For statistical analysis, a generalized linear model (GLM) was used.
Urea concentration was 11.88 ± 3.03 mg/dl in keratoconus and 16.44 ± 6.40 mg/dl in cataract patients, uric acid 2.04 ± 0.59 mg/dl in keratoconus and 2.18 ± 0.73 mg/dl in cataract groups. Prolactin concentration was 3.18 ± 0.34 ng/ml in keratoconus and 3.33 ± 0.32 ng/ml in cataract patients, fT4 20.57 ± 4.76 pmol/l in KC and 19.06 ± 3.86 pmol/l in cataract group. Urea concentration was effected through gender (p = 0.039), age (p = 0.001) and diagnosis (p = 0.025). Uric acid concentration was not effected through any of the analyzed parameters (p > 0.056). Prolactin and fT4 concentration were effected only through diagnosis (p = 0.009 and p = 0.006).
Urea and prolactin concentrations are decreased, fT4 concentration is increased in aqueous humor of keratoconus patients, and uric acid concentration remains unchanged. Urea concentration in aqueous humor is also increased in older and male patients. Therefore, metabolic disorder and hormonal balance may both have an impact on keratoconus development. Further studies are necessary to assess the specific impact.
圆锥角膜是一种与角膜进行性变薄和呈圆锥形相关的非炎症性疾病。尿素循环中的代谢改变，以及胶原纤维稳定性、氧化应激、甲状腺激素和催乳素的变化，这些对角膜基质的生物合成和生物力学稳定性具有调节作用，可能在圆锥角膜的病因学中都发挥作用。我们的目的是测定圆锥角膜患者和白内障患者房水中尿素、尿酸、催乳素和游离甲状腺素（fT4）的浓度。
从100例圆锥角膜患者（穿透性角膜移植术）（年龄41.9±14.9岁，男性69例）和100例白内障患者（白内障手术）（年龄71.2±12.4岁，男性58例）中采集房水。通过西门子临床化学或免疫分析系统测定尿素、尿酸、催乳素和fT4的浓度。进行统计分析时，使用了广义线性模型（GLM）。
圆锥角膜患者房水中尿素浓度为11.88±3.03mg/dl，白内障患者为16.44±6.40mg/dl；圆锥角膜患者房水中尿酸浓度为2.04±0.59mg/dl，白内障组为2.18±0.73mg/dl。圆锥角膜患者房水中催乳素浓度为3.18±0.34ng/ml，白内障患者为3.33±0.32ng/ml；圆锥角膜患者房水中fT4浓度为20.57±4.76pmol/l，白内障组为19.06±3.86pmol/l。尿素浓度受性别（p=0.039）、年龄（p=0.001）和诊断（p=0.025）的影响。尿酸浓度不受任何分析参数的影响（p>0.056）。催乳素和fT4浓度仅受诊断的影响（p=0.009和p=0.006）。
圆锥角膜患者房水中尿素和催乳素浓度降低，fT4浓度升高，尿酸浓度保持不变。老年患者和男性患者房水中尿素浓度也升高。因此，代谢紊乱和激素平衡可能都对圆锥角膜的发展有影响。需要进一步研究来评估具体影响。
