Hussaini S H, Henderson T, Morrell A J, Losowsky M S
Academic Division of Medicine, St James's University Hospital, Leeds, UK.
Eye (Lond). 1998;12 ( Pt 3a):419-26. doi: 10.1038/eye.1998.99.
The role of vitamin A in early primary biliary cirrhosis (PBC) remains uncertain.
We assessed dark adaptation and assayed vitamin-A-related compounds in 10 patients with early PBC and a group of age- and sex-matched controls.
In patients compared with controls: (i) mean final light threshold value was 11.8% greater (p < 0.004), (ii) time taken to see the first light stimulus was longer (2.8 +/- 0.6 vs 1.4 +/- 0.2 min, mean +/- SEM; p < 0.03) and (iii) sensitivity to light stimuli was impaired after 6 min in the dark (p < 0.03). Three patients had an abnormal final light threshold despite receiving regular vitamin A; two had a low serum vitamin A. Raised serum bilirubin and increased age were the most important determinants of impaired dark adaptation.
Patients with early PBC have modestly impaired dark adaptation, despite standard vitamin A supplementation, although these changes may not have a significant effect on visual function. Vitamin A supplementation should be recommended for older patients with jaundice, but its effect should be carefully monitored.
维生素A在早期原发性胆汁性肝硬化（PBC）中的作用仍不明确。
我们评估了10例早期PBC患者以及一组年龄和性别匹配的对照者的暗适应情况，并检测了与维生素A相关的化合物。
与对照组相比，患者：（i）最终平均光阈值高11.8%（p<0.004），（ii）看到第一个光刺激所需时间更长（2.8±0.6对1.4±0.2分钟，均值±标准误；p<0.03），以及（iii）在黑暗中6分钟后对光刺激的敏感性受损（p<0.03）。3例患者尽管接受了常规维生素A治疗，但最终光阈值仍异常；2例血清维生素A水平低。血清胆红素升高和年龄增加是暗适应受损的最重要决定因素。
尽管补充了标准剂量的维生素A，但早期PBC患者的暗适应仍有轻度受损，尽管这些变化可能对视功能没有显著影响。对于老年黄疸患者，应建议补充维生素A，但其效果应仔细监测。
