ankylosing spondylitis of his lower back / significant flare; severe SOB; severe 10.10 flank pain put him in bed; severe 10.10 flank pain put him in bed; inflammation; immune reaction flaring his HLA-B27 positive ankylosing spondylitis.; This is a spontaneous report received from a contactable reporter(s) (Physician).  A 32 year-old male patient received bnt162b2 (BNT162B2), intramuscular, administered in arm right, administration date 01Oct2021 (Batch/Lot number: unknown) at the age of 32 years as dose 1, single for covid-19 immunisation. Relevant medical history included: "Ankylosing Spondylitis" (unspecified if ongoing), notes: Other medical history: ankylosing spondylitis, asthma, ADHD; "Asthma" (unspecified if ongoing), notes: Other medical history: ankylosing spondylitis, asthma, ADHD; "Adhd" (unspecified if ongoing), notes: Other medical history: ankylosing spondylitis, asthma, ADHD; "Known allergies: raw tomato" (unspecified if ongoing), notes: Known allergies: raw tomato. Concomitant medication(s) included: VYVANSE; ALBUTEROL [SALBUTAMOL]; IBU; COSENTYX. Past drug history included: Gabapentin, reaction(s): "known allergies: Gabapentin", notes: known allergies: Gabapentin. The following information was reported: ANKYLOSING SPONDYLITIS (medically significant) with onset 01Oct2021, outcome "recovered with sequelae", described as "ankylosing spondylitis of his lower back / significant flare"; DYSPNOEA (non-serious) with onset 01Oct2021, outcome "recovered with sequelae", described as "severe SOB"; FLANK PAIN (non-serious), BEDRIDDEN (non-serious) all with onset 01Oct2021, outcome "recovered with sequelae" and all described as "severe 10.10 flank pain put him in bed"; INFLAMMATION (non-serious) with onset 01Oct2021, outcome "recovered with sequelae", described as "inflammation"; IMMUNE SYSTEM DISORDER (non-serious) with onset 01Oct2021, outcome "recovered with sequelae", described as "immune reaction flaring his HLA-B27 positive ankylosing spondylitis.". The events "ankylosing spondylitis of his lower back / significant flare", "severe sob", "severe 10.10 flank pain put him in bed", "severe 10.10 flank pain put him in bed", "inflammation" and "immune reaction flaring his hla-b27 positive ankylosing spondylitis." were evaluated at the physician office visit and emergency room visit. The patient underwent the following laboratory tests and procedures: sars-cov-2 test: (22Dec2021) negative, notes: Nasal Swab. Therapeutic measures were taken as a result of ankylosing spondylitis, dyspnoea, flank pain, bedridden, inflammation, immune system disorder. Clinical course: Patient had not taken any other vaccine in four weeks. Patient initially had severe shortness of breath and inhaler was helpful, this resolved and now with severe 10.10 flank pain put him in bed. Reporter considering this a true adverse reaction to the covid immunization. This is likely associated with his corresponding ankylosing spondylitis of his lower back. He had to come off of his cosentyx to receive the immunization. Reporter sincerely said this patient is not trying to just skirt around the covid vaccination. He actually wants to receive the covid vaccination and came off of his medicine to do so. He has had little or nothing to do with his mandate. He wanted to do this sooner but it was recommended by his rheumatologist to wait until he could come off of his medication and receive the immunization. He did so by stopping the medication and receive the covid immunization and is having a significant flare. This is likely secondary to the inflammation caused by the immunization and an immune reaction flaring his HLA-B27 positive ankylosing spondylitis. Patient recovered with lasting effects. Adverse event treatment steroid and inhaler was given. Patient had not taken covid prior vaccination. Patient covid tested post vaccination. Covid test type post vaccination was nasal swab.  The lot number for bnt162b2 was not provided and will be requested during follow up.; Sender's Comments: Based on the information provided in the narrative, a causal association between the suspect drug and the events cannot be completely 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.