Blood clot; Pulmonary embolism that resulted from a DVT in leg; Pulmonary embolism that resulted from a DVT in leg; Shortness of breath; sinus infection; This is a spontaneous report from a contactable nurse (patient). A 74-year-old female patient received second dose of BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE, solution for injection, lot number: EI9266, expiry dates was not reported), via unspecified route of administration, on 12Mar2021, as DOSE 2, SINGLE for COVID-19 immunization. The patient's medical history included hyperthyroidism, blood pressure high and ongoing asthma, all were from unspecified start date and stop date. Concomitant medications included prednisone, levothyroxine sodium (SYNTHROID), amlodipine besilate (NORVASC) and losartan, all were for unspecified indication. The patient historical vaccine included first dose of BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE, solution for injection, lot number: EN6206, expiry dates was not reported), via unspecified route of administration, on 12Feb2021, as a single dose, for COVID-19 immunization. Patient had blood clot, pulmonary embolism that resulted from a DVT in leg, shortness of breath and sinus infection, on an unknown date in Mar2021. Patient stated that, she had blood clot after received the vaccine. Patient got the Pfizer vaccine, first shot on 12Feb2021 and second shot on 12Mar2021 and about two weeks after that patient started getting symptoms shortness of breath and patient was just diagnosed three weeks ago with a pulmonary embolism that resulted from a DVT in leg and they are not sure when that occurred. Patient started with shortness of breath and was an asthmatic, so pulmonologist thought it was the asthma that was acting up then they thought patient had a sinus infection and it just kept getting worse and worse the shortness of breath. Patient stated that, pulmonologist was trying to figure out what could have caused this, they thought it was asthma acting up but apparently shortness of breath kept getting worse and three weeks ago patient was hospitalized and that when they found this large pulmonary embolism and when they did the 'legs' they found the clot in the legs and they could not determine the age of it when that occurred, but it would be before patient had the COVID shot. Patient did not receive any other vaccine administered prior COVID-19 vaccine. Patient was hospitalized from 08Jun2021 to 12Jun2021. Patient was clarified the reason of hospitalized as blood clots. Patient was seeing pulmonologist, they did a CAT scan in Feb2021 and that was clear. They also did a cardiac catheterization in Apr2021, thinking that's why patient was short of breath but that was normal. Patient was in the hospital, they did everything under the 'sun'. When patient was in the hospital, they put on a Heparin drip for two days and now on a blood thinner Eliquis. Outcome of the event shortness of breath was not recovered/not resolved and for other events outcome was unknown.   Information on Lot/Batch number was available. Additional information has been requested.; Sender's Comments: Based on the information in the case report and a plausible temporal relationship, a possible causal relationship between the events Thrombosis, Pulmonary embolism, Deep vein thrombosis, Dyspnoea and Sinusitis and suspect drug BNT162B2 cannot be excluded. 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.