The EOG in rheumatoid arthritis.

In untreated rheumatoid arthritis 20% of the patients has a EOG Lp/Dt ratio lower than the lower 5% limit calculated for normal patients. The EOG is more often disturbed in a long-standing chloroquin-induced retinopathy than in the acute phase of intoxication, the reason being progression from a maculopathy to a tapeto-retinal degeneration. The subnormal EOG in rheumatoid arthritis might be due to an auto-immune process against rhodopsin and uveal pigment. Withdrawal of synthetical antimalarial agents in cases suspected of an early drug-induced retinopathy based on EOG subnormality may enhance the underlying rheumatoid process thus causing a further decrease of the EOG. The EOG therefore is not a method of choice in detecting an early chloroquin-induced retinopathy.