Activated protein C resistance in anterior ischaemic optic neuropathy.
OBJECTIVE
Protein C is a major component of the natural anticoagulant pathway. Resistance of coagulation factor V (FV) to activated protein C (APC), mostly due to FV Leiden mutation, is the most common cause of inherited thrombophilia. The aim of this retrospective study was to determine the prevalence of APC resistance and Leiden mutation in patients with non-arteritic anterior ischaemic optic neuropathy (NAION).


METHODS
A total of 25 patients with NAION were examined between 1997 and 2002. The patients were screened for APC resistance and FV Leiden mutation as well as for acquired risk factors of vascular disease such as diabetes mellitus, hypercholesterolaemia, hypertonia and ischaemic heart disease. A control group of subjects without ocular vascular disease and with homogenous distribution of the same risk factors was used for comparison.


RESULTS
Six of the 25 patients (24%) with NAION had APC resistance due to the heterozygous Leiden mutation of FV. The frequency of the same genetic mutation in the control group was only 5.9%. Odds ratio calculations showed that patients with the Leiden mutation were at a significantly higher risk of NAION than control patients (p < or = 0.021).


CONCLUSIONS
The high frequency of Leiden mutation in NAION suggests a pathogenic role of the mutation in the disease.
Nagy
Valeria
V
Department of Ophthalmology, Medical and Health Science Centre, University of Debrecen, Debrecen, Hungary. vnagy@jaguar.dote.hu
Facsko
Andrea
A
Takacs
Lili
L
Balazs
Erzsebet
E
Berta
Andras
A
Balogh
Istvan
I
Edes
Istvan
I
Czuriga
Istvan
I
Pfliegler
Gyorgy
G
D020016:Activated Protein C Resistance / Q000150:complications* / Q000235:genetics; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005165:Factor V / Q000235:genetics; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018917:Optic Neuropathy, Ischemic / Q000150:complications* / Q000235:genetics; D017354:Point Mutation; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D013927:Thrombosis / Q000209:etiology
C095381:factor V Leiden; D005165:Factor V