Plasma homocysteine and cysteine levels in retinal vein occlusion.
OBJECTIVE
To determine plasma homocysteine and cysteine levels in patients with retinal vein occlusion (RVO) and in healthy subjects and to ascertain whether there are statistically significant differences between patients and control subjects.


METHODS
In this case-control study, the study group consisted of 75 consecutive patients with RVO: 33 had central retinal vein occlusion (CRVO), and 42 had branch retinal vein occlusion (BRVO). Seventy-two apparently healthy age- and sex-matched subjects served as control subjects. Homocysteine and cysteine levels were measured with a new laser-induced fluorescence capillary electrophoresis (CE-LIF) METHOD: Wilcoxon or Student's t-test was used, when appropriate, to determine differences between groups.


RESULTS
There were no significant differences in median plasma homocysteine between patients with RVO and control subjects, nor were there any statistically significant differences when patients were categorized by type of vein occlusion (CRVO or BRVO). Similarly, there were no significant differences in mean plasma cysteine between patients with RVO and control subjects. However, when categorized by type of vein occlusion, mean plasma cysteine was significantly higher in CRVO patients than in control subjects (P = 0.034).


CONCLUSIONS
This study failed to demonstrate an association between increased plasma homocysteine and RVO. Mean plasma cysteine was significantly higher in patients with CRVO, suggesting that hypercysteinemia may contribute to the pathogenesis of this retinal vascular disorder.
Pinna
Antonio
A
Institute of Ophthalmology, University of Sassari, Sassari, Italy. apinna@uniss.it
Carru
Ciriaco
C
Zinellu
Angelo
A
Dore
Stefano
S
Deiana
Luca
L
Carta
Francesco
F
D000368:Aged; D016022:Case-Control Studies; D003545:Cysteine / Q000097:blood*; D019075:Electrophoresis, Capillary / Q000379:methods; D005260:Female; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012170:Retinal Vein Occlusion / Q000097:blood*
D006710:Homocysteine; D003545:Cysteine