Subhyaloid hypopyon as a diagnostic cue in syphilitic necrotizing retinitis.

Purpose: To describes one case of syphilitic necrotizing retinitis and one case of presumed syphilitic necrotizing retinitis with presence of subhyaloid hypopyon.
Case Description: We report two cases of necrotizing retinitis, which were noted to have yellow boat-shaped lesions at the inferior edge of retinitis resembling subhyaloid hypopyon. The subhyaloid location was confirmed on optical coherence tomography in one case. Both the cases were positive for venereal disease research laboratory test (VDRL) and Treponema pallidum hemagglutination (TPHA). But in one case, polymerase chain reaction (PCR) of the aqueous humor was positive for Pseudomonas aeruginosa and responded well to piperacillin. As piperacillin is effective against Pseudomonas and the efficacy of piperacillin in the management of syphilis is not studied, we may have to consider it as a case of presumed syphilitic retinitis.
Discussion: Subhyaloid hypopyon is an uncommon presentation and is reported in two cases of syphilitic necrotizing retinitis in literature. Severe infection and necrosis confined to the inner retina leads to collection of white blood cells and necrotic material in the subhyaloid space and would settle down resulting in subhyaloid hypopyon. Two cases of subhyaloid hypopyon reported in literature and 2 cases reported in our article are syphilitic retinitis and is not reported in other entities.
Conclusion: It is possible that subhyaloid hypopyon may serve as a diagnostic cue in syphilitic necrotizing retinitis.