Pancreatitis in tail of pancreas; fever (101.2F) for four days; left side abdominal pain; diverticulitis; headache; This is a spontaneous report from a contactable physician reporting on behalf of patient. A 66-year-old male patient received BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE) via an unspecified route of administration on 08Apr2021 (Batch/Lot Number: EP7533) as 1st dose single for covid-19 immunisation. Medical history included ongoing high cholesterol which was diagnosed decades ago at least, kidney stone. Concomitant medication included simvastatin (strength: 20mg) from 2011 and ongoing. No additional vaccines administered on same date of the Pfizer suspect. The reporting physician is the patient's primary care physician. The patient came to the physician's office on 16Apr2021 for the fever, left sided abdominal pain, and headache which had been going on for 4 days in Apr2021.  Physician reported that the patient thought his left-sided abdominal pain was caused by a kidney stone. Because of the high fever of 101.2 and the persistence of 4 days of fever, the patient was admitted to the hospital. Patient had an elevated white blood cell count of 13000.  The patient had a very high D-dimer test which kept rising. The patient's C-Reactive Protein was very high. white blood cell count was 12.6 on admission and went to 6.8 after IV antibiotics were administered. The patient's fever resolved within 24 hours of starting IV antibiotics and fluids. When queried for seriousness criteria, physician reported that the patient's headache was just nagging.  Physician reported that he doesn't have the patient's chart, but he is guessing that the patient's headache resolved within 3 days of admission to hospital. Regarding pancreatitis in tail of pancreas, physician reported that there was a possibility that the patient's abdominal pain was diverticulitis, it was unclear if the inflammation was from diverticulitis or the pancreas.  Physician reported that the patient had a GI consult.  Physician reported that the GI provider did an MRI on the patient's abdomen and the final word was pancreatitis. Physician reported that since the patient was hospitalized, all of the inflammatory markers, D-dimer, sed rate, CRP, have come down.  Physician stated something happened.  The patient has no risk factors for pancreatitis. He doesn't drink, isn't on any medications that would cause pancreatitis, doesn't have high triglycerides, and doesn't have gallstones; the Pfizer Covid-19 vaccine was the only variable.  Physician is thinking that the whole inflammatory process was part of a reaction to the Covid-19 vaccine. Patient is clinically recovered, he was hospitalized from 16Apr2021 to 22Apr2021. Physician reported that the patient hasn't been checked radiologically but the physician is hoping to repeat the patient's MRI in a couple of weeks. He eventually got better and went home.  He is now wondering if he should get the second dose of the Covid-19 vaccine. Physician is a little hesitant to tell the patient whether or not the patient should get the second dose of the Covid-19 vaccine.  Physician does not know if the patient's adverse events were related to the Covid-19 vaccine and stated that risking another pancreatitis episode is a big deal. The patient's lipase never went up unless it was high 4 days before admission.  Physician reported that the patient didn't seek attention then. Patient underwent lab tests and procedures which included D-dimer: 416ng/mL (16Apr2021), 959 ng/mL (18Apr2021), 933 ng/mL (19Apr2021), 818 ng/mL (20Apr2021), 842 ng/mL (21Apr2021), 686 ng/mL (22Apr2021); White blood cell count: 12600 (16Apr2021), 6800 (22Apr2021); C-reactive Protein: 148 ng/mL (16Apr2021), 109 ng/mL (18Apr2021), 84 ng/mL (20Apr2021), 73 ng/mL (21Apr2021), 51 ng/mL (22Apr2021), less than 1 ng/mL (12May2021); CT abdomen (16Apr2021): Inflammation in tail of pancreas; Covid-19 test: negative on 16Apr2021 and 18Apr2021; Erythrocyte sedimentation rate: 68 mm/hour (19Apr2021), 20 mm/hour (12May2021); Blood cultures: negative on 16Apr2021; Alk phos: 123 IU/L (26Apr2021), 85 IU/L (12May2021); ALT: 46 IU/L (26Apr2021), 40 IU/L (12May2021); GGT (Normal range: Up to 65 IU/L): 92 IU/L (30Apr2021), 59 IU/L (12May2021); CT angiogram chest, abdomen, pelvis on Apr2021 and revealed negative, no thrombotic event (Apr2021). MRI Abdomen: Pancreatitis localized to tail of pancreas (Apr2021); CT head was Negative (Apr2021). Outcome of diverticulitis was unknown, outcome of other events was recovered in Apr2021.   The reporting physician assessed fever as serious with seriousness criteria hospitalization, left sided abdominal pain is serious with seriousness criteria medically significant and pancreatitis is serious with seriousness criteria medically significant, disabling.   Physician reported that the Covid-19 vaccine potentially yes caused the patient's abdominal pain, but he did not know if the headache and pancreatitis were related or not to the Pfizer Covid-19 vaccine.  Physician reported that in the absence of anything else, he is suspecting that the patient's headache and pancreatitis were caused by the Covid-19 vaccine.   No follow-up attempts are needed. No further information is expected.; Sender's Comments: Based on the information currently available, a contributory role of BNT162B2 to reported events cannot be fully excluded. Case will be reassessed if additional information becomes available.  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.