Improvement of graft prognosis in penetrating normal-risk keratoplasty by HLA class I and II matching.
BACKGROUND
Owing to contradictory results, HLA matching in penetrating keratoplasty still is equivocal. Different surgical techniques in multicentre studies, missing risk differentiation in high-risk situations, and faulty HLA typing can be identified as main reasons for these contradictory results. In this monocentre study, the value of HLA class I and II matching (A, B, DR loci) was examined in a homogeneous group of 418 normal-risk keratoplasty patients using serological typing techniques for HLA class I and immunogenetic typing techniques for class II.


METHODS
Penetrating normal-risk keratoplasty was performed in two groups of patients (group I with 0-2, group II with 3-6 mismatches in the A/B/DR loci). All surgery was carried out by three experienced surgeons according to a standardized scheme. Furthermore, postoperative therapy and controls were standardized. There were no statistically significant differences between the two study groups with regard to the number of ABO or H-Y compatibilities, patient age, patient gender, ratio of previous intraocular surgery, ratio of triple procedures, indication for surgery, follow-up period, donor age, donor gender, post-mortem time of the graft, and endothelial cell density of the graft at the end of organ culture. All HLA typing was performed in a quality-controlled laboratory, serologically for HLA class I (A and B loci) and immunogenetically for HLA class II (DR locus).


RESULTS
At 4 years postoperatively, the ratio of clear and rejection-free graft survival was 92% in group I and 66% in group II (Kaplan-Meier estimation, log rank test, P=0.03). Monovariate analysis in the Cox model gave no influence of solitary HLA class I or II matching, but only an influence of combined HLA class I and II matching (P=0.03).


CONCLUSIONS
In this monocentre study with proper typing techniques, the beneficial effect of HLA class I plus II matching on clear and rejection-free graft survival could be demonstrated in a homogeneous group of normal-risk keratoplasty patients.
Reinhard
T
T
Eye Hospital, Albert-Ludwigs University Freiburg, Germany. Reinhard@aug.ukl.uni-freiburg.de
Böhringer
D
D
Enczmann
J
J
Kögler
G
G
Mayweg
S
S
Wernet
P
P
Sundmacher
R
R
D000017:ABO Blood-Group System / Q000276:immunology; D000704:Analysis of Variance; D016039:Corneal Transplantation / Q000276:immunology*; D042783:Endothelial Cells / Q000276:immunology; D005260:Female; D006084:Graft Rejection / Q000276:immunology; D006085:Graft Survival / Q000276:immunology*; D006182:H-Y Antigen / Q000276:immunology; D006680:HLA Antigens / Q000276:immunology*; D006650:Histocompatibility Testing / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D011182:Postoperative Care / Q000379:methods; D011379:Prognosis; D012307:Risk Factors
D000017:ABO Blood-Group System; D006182:H-Y Antigen; D006680:HLA Antigens