A fit-and-well 28-year-old man presented to our emergency room with a 2-day history of blurred vision in his right eye. He mentioned he always had lower VA in his left eye, and no prior history of ocular disease was reported. He had presented with myalgia and headache one week earlier, which resolved spontaneously. His BCVA was 20/40 in the right eye and 20/25 in the left eye. Slit-lamp biomicroscopy was unremarkable. Dilated fundus examination exhibited a hyperemic optic disc, peripapillary edema, and multiple yellowish-white placoid lesions in the posterior pole, some involving the foveal area, bilaterally (Figure 1). General examination was unremarkable.
Fundus autofluorescence (FAF) showed hypoautofluorescent lesions with an area of relative hyperautofluorescence along their edge (Figure 2). Hypofluorescence at the placoid lesions in the early phase that changed to hyperfluorescence at the late phases was evident on fluorescein angiography (FA) (Figures 3(a) and 3(b)). Indocyanine green angiography (ICGA) evidenced hypofluorescence of placoid lesions from early to late phases (Figures 4 and 5(a)). OCT (Avanti RTVue-XR 100, Optovue Inc., Fremont, CA) demonstrated bilateral focal areas of disruption of the ellipsoid layer and hyperreflectivity in the outer retina, primarily localizing to the outer nuclear layer (ONL) but also being seen at the level of the outer plexiform layer (Figure 5(c)). These features were more evident in the right eye. OCTA revealed significant hypoperfusion at the level of the choriocapillaris in the active lesions bilaterally (Figure 5(b)).
Due to the potential association with central nervous system (CNS) abnormalities, the patient was observed by the Department of Neurology. Neurologic examination, cranioencephalic-computerized tomography, and cervical and transcranial Doppler ultrasonography were unremarkable.
Extensive work-up to rule out other pathologies that could mimic APMPPE, including infectious diseases, was performed. This included serology for syphilis, herpes simplex 1 and 2, cytomegalovirus, Epstein-Barr, varicella zoster, Borrelia, HIV 1 and 2, and QuantiFERON-TB Gold test, which were all negative for active infection. Complete blood count, angiotensin conversion enzyme, hepatic enzymes, renal function, and thorax X-ray were unremarkable. C-reactive protein and sedimentation velocity were increased (3.86 mg/dL and 31 mm/h, respectively).
Regarding the differential diagnosis, we excluded syphilis, tuberculosis, other infectious causes, Vogt-Koyanagi-Harada disease, and sarcoidosis, based on the history, the results of laboratory tests, and the lack of systemic findings. The presence of a previous viral prodrome, the young age, and the multiple yellowish-white placoid lesions in the posterior pole pointed to an inflammatory choriocapillaropathy. The morphology of the lesions helped in the discrimination of the white dot syndrome, as the placoid conformation with lesions bigger than 125 mum with a low degree of inflammation was in favor of APMPPE or serpiginous choroiditis. However, the choroiditis' geographical pattern with centrifugal extension from the peripapillary region typical of serpiginous choroiditis was not observed. Instead, the deep multiple yellowish-white placoid lesions in the posterior pole associated with a minimal vitreous inflammation in a young healthy male with a negative QuantiFERON-TB Gold test are favorable of the diagnosis of APMPPE. The fact that the lesions resolved over time without recurrences was also in favor of this diagnosis. There are relentless serpiginous and ampiginous forms that can mimic APMPPE.
The placoid lesions in APMPPE spontaneously resolve in most cases, and VA usually recovers within a few months. However, there are reports of permanent changes and therapy with corticosteroids may have a role when there is foveal involvement, advanced age, unilateral disease, and recurrences or risk of central nervous system vasculitis. Due to centromacular involvement, the patient started treatment with 1 mg/kg/day of methylprednisolone.
After two weeks, the patient presented functional and anatomical improvement. BCVA was 20/30 in his right eye and 20/22 in the left eye. Slit-lamp examination remained unremarkable, and at dilated fundus examination, it was possible to note placoid macular lesions in resolution (Figure 6). No de novo lesions were observed. SD-OCT demonstrated resolution of macular edema and focal atrophy of outer retinal layers corresponding to the previous hyperreflective areas (Figure 7). OCTA showed reperfusion of the choriocapillaris in the affected placoid areas, in both eyes (Figure 8).
At this time, methylprednisolone was tapered off to 48 mg/day and a reevaluation was scheduled to two weeks later. Unfortunately, the patient missed these and the subsequent appointments. A head magnetic resonance imaging requested by the neurology department was also missed.