Increased aqueous lactate dehydrogenase in Coats' disease.

A 3-year-old boy had glaucoma and a total left retinal detachment that displayed peripheral intraretinal telangiectasis. The most probable clinical diagnosis was Coats' disease. A suspicion of retinoblastoma also existed, and an aqueous aspirate was assayed for lactate dehydrogenase (LDH) and found to contain three times the level present in a matching sample of serum. We enucleated the eye and verified the diagnosis of Coats' disease pathologically. The results of aqueous LDH determinations in eyes with glaucoma, phthisis, or large numbers of histiocytes, erythrocytes, and polymorphonuclear leukocytes should be interpreted with caution.