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Editor,—Retinal inflammations generally present in varied but fairly characteristic patterns. The advent of penicillin almost wiped out syphilis; however, there has been an increase in the incidence of syphilitic infections reported over the past decade. This protean infection can mimic many others and produces unusual lesions anywhere in the eye.
A 20-year-old male patient presented with hazy vision and pain in the right eye for 2 weeks. There was no history of similar complaints in the past. The patient did not suffer from oral or genital ulcers or any other systemic illnesses.
On examination, the visual acuity was 20/200 in the right eye and 20/20 in the left. The anterior segment was essentially within normal limits.
On examination of the right fundus (Fig 1) the patient was found to have a yellow-white preretinal exudation and vitritis over 5–6 disc diameters above the macula and over the superotemporal retinal vessels. The inferior part of this exudation was in the form of a preretinal ‘hypopyon’. The surrounding vessels, both arterial and venous, showed active vasculitis, and the disc was congested and full, with peripapillary retinal oedema. There were folds around the macula.
The patient was investigated serologically before starting any medication. His total leucocyte count was 9.7 × 106/l, the differential count had 87% neutrophils and his erythrocyte sedimentation rate was 14 mm in first hour. The Mantoux test and IgG/IgM for Toxoplasma were negative. The fluorescent treponemal antibody absorption test was positive and the VDRL was positive in a titre of 1:16. All tests for HIV were negative. The cerebrospinal fluid analysis was normal. The fluorescein angiogram showed an early and marked leak from the disc. The superotemporal vessels were tortuous and irregular with a perivascular leak which increased over time leading to hyperfluorescence in the area of the preretinal ‘hypopyon’ (Figs2, 3, 4).
The patient was given penicillin G benzathine 2.4 million units intramuscularly on the first day and weekly for 2 weeks. After 2 days of the penicillin therapy the vision in the right eye improved to 20/40 and the vitreous exudation had cleared, revealing extensive sheathing of blood vessels and focal infiltrates in the preretinal region. The preretinal ‘hypopyon’ was also more localised. One week after institution of the penicillin therapy the ‘hypopyon’ had resolved completely leaving the superotemporal retinal oedematous with narrowed and sheathed venules and arterioles. Preretinal focal infiltrates persisted above the macula, temporal to the disc and in the superotemporal retina. The disc oedema had also resolved to a large extent, though the margins were still blurred and minimal peripapillary oedema persisted (Fig 5). After 4 weeks the vision was 20/20 with no deficit on an Amsler grid evaluation and the focal infiltrates had completely resolved, leaving a mottled superotemporal retina, narrowed and sheathed vessels superotemporally, and a pale disc with ill defined margins.
The clinical manifestations of acquired syphilitic neuroretinal involvement are described as a patchy diffuse retinal oedema with associated vitritis, vasculitis (generally arterial), and occasionally haemorrhages.1-5 Preretinal exudates were described by Calmettes and Deodati in 1947, as quoted by Duke-Elder, but are not a common feature of this disease.
Behçet’s disease generally presents with a hypopyon in the anterior chamber but involvement of the posterior segment in the form of an arterial occlusion can lead to infarction of large areas of the retina and is accompanied by intense retinal oedema, haemorrhage, and vitreous opacification which resemble the retinitis and vitritis commonly seen in secondary syphilis.6
A retinal pseudohypopyon-like picture has been described in patients with Best’s vitelliform dystrophy where partial resorption of the premacular yellowish material simulates an exudative reaction. A subretinal hypopyon was reported in a patient with prolymphocytic leukaemia, wherein the contents were presumed to be an accumulation of abnormal lymphocytes.7
Our patient had severe syphilitic retinal vasculitis with a hitherto unreported picture of a preretinal ‘hypopyon’ which cleared dramatically in response to penicillin therapy.