Thyroid dysfunction and uveitis.

In 544 patients with uveitis, those with presumptive diagnoses of toxoplasmosis, tuberculosis, sarcoidosis, toxocariasis, and "unknown" had significant hypothyroidism (defined as a thyroxine level below 5.3 microgram/dL). Those with diagnoses of histoplasmosis, syphilis, rheumatoid arthritis, Fuchs'heterochromic iridocyclitis, serpiginious choroiditis, or HLA B27 did not have such low levels. No diagnostic entities showed significant hyperthyroidism (defined as a thyroxine level of 12.0 microgram/dL or more). All results were based on thyroxine levels; further studies should employ more modern techniques.