A 45-year-old man with no relevant past medical history presented to the eye casualty service complaining of sudden onset central 'white ring' and decreased vision in the right eye (RE) over the past seven days. Best-corrected visual acuity (BCVA) was 6/12 in the right eye and 6/6 in the left eye (LE). Intraocular pressure was 14 mmHg in both eyes. Examination of the RE showed no cells in the right anterior chamber and 1+ vitreous cells; fundus examination revealed a yellow placoid lesion involving the macular area with no signs of vasculitis or retinal necrosis. Examination of the LE was unremarkable.
MMI of the retina including colour fundus photograph, fundus autofluorescence, SD-OCT, fluorescein angiography and indocyanine green angiography are presented in Figure 1 (Fig. 1), Figure 2 (Fig. 2), and Figure 3 (Fig. 3).
The medical history was carefully reviewed; the patient admitted to be addicted to poppers and cocaine, and reported promiscuous homosexual activity over the last months. He denied intravenous drug use and any systemic symptoms such as headache, skin rash, nausea, weight loss, cough, or night sweats. A complete laboratory work-up was ordered, including TB QuantiFERON-TB testing, syphilis serology and human immunodeficiency virus (HIV) antibodies. Seven days after presentation, the patient reported spontaneous improvement in the vision of the RE, and BCVA improved to 6/9 in the RE and was stable in the LE. Full blood count, liver function test, kidney function, angiotensin-converting enzyme level were within normal range, HIV antibodies were negative. However, results for QuantiFERON-TB testing and syphilis had not been available yet. MMI revealed spontaneous improvement of the placoid lesion (Figure 2 (Fig. 2), Figure 3 (Fig. 3)).
Two weeks after presentation, BCVA further improved to 6/6 in the RE and MMI showed signs of early resolution of the placoid lesion. Laboratory results returned negative for QuantiFERON-TB testing, and positive for venereal disease research laboratory test and fluorescent treponemal antibody testing. Therefore, a definite diagnosis of ASPPC was made, and the patient was promptly referred to the Infectious Disease Department for systemic treatment with penicillin.