Acute Posterior Multifocal Placoid Pigment Epitheliopathy Presenting with Multiple Serous Retinal and Bacillary Layer Detachments: A Diagnostic Challenge.

Purpose: To describe a diagnostically challenging case of Acute Posterior Multifocal Placoid Pigment Epitheliopathy (APMPPE) in a young girl, presenting with features mimicking Vogt-Koyanagi-Harada (VKH) syndrome. Methods: An 18-year-old Asian Indian girl presented with sudden bilateral visual diminution and metamorphopsia for three days. Clinical examination and multimodal imaging were performed, including Enhanced Depth Imaging Optical Coherence Tomography (EDI-OCT), Fundus Fluorescein Angiography (FFA), Indocyanine Green Angiography (ICG), and Optical Coherence Tomography Angiography (OCTA). Systemic evaluation included the Mantoux test, QuantiFERON-TB Gold, HRCT of the chest, abdominal ultrasonography, and routine blood work. Results: BCVA was 20/40 in both eyes. Fundus examination revealed mild vitritis, multiple serous retinal detachments (SRD), and yellowish placoid lesions at the posterior pole. EDI-OCT showed SRD with bacillary layer detachment and mild choroidal thickening in both eyes. FFA revealed early hypofluorescence with late staining; ICG showed persistent hypocyanescent lesions localized to the posterior pole. OCTA demonstrated choriocapillaris flow voids. Mantoux and QuantiFERON-TB Gold were strongly positive; other systemic investigations were unremarkable. Given the absence of VKH prodromal features and features on multimodal imaging, a diagnosis of APMPPE was made. The patient was observed without corticosteroid therapy, and complete resolution of SRD and bacillary layer detachment occurred within 1 week. Discussion: The initial presentation with bilateral SRDs and BALADs strongly suggested VKH syndrome. However, the absence of systemic prodromal symptoms, combined with characteristic angiographic features, led to a diagnosis of APMPPE. The rapid, spontaneous resolution of these atypical detachments without corticosteroid therapy further confirmed the self-limiting nature of APMPPE, in sharp contrast to the prompt immunosuppression typically required for VKH. Conclusion: APMPPE can rarely present with atypical clinical features such as SRD and BALAD. Clinicians must integrate multimodal imaging with systemic evaluations to accurately differentiate it from VKH syndrome, thereby preventing misdiagnosis and avoiding unnecessary treatment.