corneal endothelial graft rejection; decrease in visual acuity in the right eye/By day 9, she noticed a decrease in the visual acuity in her left eye; By day 8 postadministration of the vaccine, her symptoms progressed to pain in the right eye; By day 8 postadministration of the vaccine, her symptoms progressed to photophobia in the right eye; the patient felt her driving was now limited by the decrease in vision in both eyes; mild arm soreness  Owing to its rapid development, short-term and long-term effects of the COVID-19 vaccine are still not well understood. This case report highlights bilateral corneal endothelial graft rejection after administration of the Pfizer COVID-19 vaccine. A 73-year-old woman with bilateral Descemet stripping endothelial keratoplasty presented with bilateral decreased visual acuity, ocular pain, and photophobia after her second dose of the Pfizer-BioNTech COVID-19 vaccine. Two weeks after vaccine administration, the uncorrected visual acuity was 20/70 and 20/40. Central corneal thickness as measured by ultrasound was 809 and 825 um and by Scheimfplug imaging was 788 and 751 um at the pupil center. Slit lamp biomicroscopy revealed quiet conjunctiva and sclera but was significant for thickened corneas with Descemet folds in both eyes. The patient was instructed to use prednisolone acetate 1% every 1 to 2 hours with Muro ointment at bedtime.  Follow-up (30Sep2021): This is a follow-up report based on the receipt of the publication; the case has been updated to include additional information identified in the publication.   A 73-year-old woman presented with bilateral decreased visual acuity, ocular pain, and photophobia after her second dose of the Pfizer-BioNTech COVID-19 vaccine. The patient's first dose of the COVID-19 vaccine was similarly the Pfizer-BioNTech vaccine. She denied any known history of infection with SARS-CoV-2. Eight years before presentation, she underwent DSEK in both eyes for Fuchs dystrophy. Postoperatively, the patient followed a topical prednisolone taper that improved her visual acuity within the first year and resolved any postoperative corneal edema. There were no known episodes of rejection in the interim period, although 2 years ago she experienced burning and blurred vision that improved with TobraDex ointment three times a day. Both administrations of the Pfizer-BioNTech COVID-19 vaccine were unremarkable during injection, and the patient reported no immediate symptoms with either dose except for mild arm soreness. Four days after her second dose of the vaccine, she first noted a decrease in visual acuity in the right eye. By day 8 post administration of the vaccine, her symptoms progressed to pain and photophobia in the right eye. By day 9, she noticed a decrease in the visual acuity in her left eye. She initially presented to our practice on day 11 after the vaccine, at which point the visual acuity was 20/200 in the right eye and 20/40 in the left. Slit-lamp examination revealed edema in the right cornea. By day 13, the patient felt her driving was now limited by the decrease in vision in both eyes. Uncorrected visual acuity was 20/ 70 and 20/40, and intraocular pressure was 8- and 9-mm Hg in the right and left eyes, respectively. Central corneal thickness as measured by ultrasound was 809 and 825 mm and by Scheimfplug imaging was 788 and 751 mm at the pupil center. Slit lamp biomicroscopy revealed quiet conjunctiva and sclera but was significant for thickened corneas with Descemet folds in both eyes. No keratic precipitates were present, and no anterior chamber cell was visible, although the view was limited through the cornea. The patient was instructed to use prednisolone acetate 1% four times per day in both eyes for 1 month to address the edema. By day 28, the eyes had become more painful. The visual acuity was 20/150 in the right and 20/80 in the left. Both eyes had 1+ cell in the anterior chamber with mild folds. Prednisolone was increased to every 1 to 2 hours daily, and Muro ointment was added at bedtime. On day 36, the patient reported that her symptoms had greatly improved, although she continued to experience morning vision blurriness in her right eye. Steroid drop frequency was reduced to 4 times per day. Approximately 2 months after graft rejection, visually significant posterior capsular opacification was noted bilaterally (2+ right and 1+ left). The right cornea had areas of superficial punctate keratitis and edema with few folds, although the left cornea had markedly decreased edema. However, the visual acuity was improved bilaterally, with 20/50 in the right eye and 20/ 25 in the left eye. In this case report, the authors present a case of bilateral corneal endothelial rejection in a 73-year-old woman after she received the second dose of the Pfizer-BioNTech SARS-CoV-2 vaccine. Association with the vaccine is suggested by three factors: the temporal association with onset after vaccine administration, the progressive worsening during this time period, and the bilateral nature of the edema. Although the widespread distribution of vaccines implies that some independent cases of graft failure will appear around the same time that patients receive the vaccine, the bilateral nature of this case raises suspicion that a common cause likely precipitated the decline of the grafts, given how infrequently bilateral rejection occurs in practice. The patient in this case report underwent DSEK 8 years before vaccine administration, making the patient's grafts the longest standing to have experienced rejection after COVID-19 vaccine administration. Notably, the patient began to experience symptoms only 4 days after the second dose of the vaccine.; Sender's Comments: Based on possible dose- event relationship post-vaccination  the causal role of BNT162B2 vaccine cannot be excluded for the reported event   The impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified to regulatory authorities, Ethics Committees, and Investigators, as appropriate