Chronic Obstructive Pulmonary Disease Exacerbation Following the Administration of a COVID 19-Booster Vaccine; interchange of vaccine products; The initial case was missing the following minimum criteria: unidentifiable patient. Upon receipt of follow-up information on 09Nov2022, this case now contains all required information to be considered valid.  This is a literature report.  A 75-year-old female patient received BNT162b2 (BNT162B2), as dose number unknown (booster), single (Batch/Lot number: unknown) for covid-19 immunisation. The patient's relevant medical history included: "COPD" (unspecified if ongoing); "paroxysmal atrial fibrillation" (unspecified if ongoing), notes: on a direct oral anticoagulant; "hypertension" (unspecified if ongoing); "hyperlipidemia" (unspecified if ongoing); "obstructive sleep apnea" (unspecified if ongoing); "not smoke" (unspecified if ongoing). The patient's concomitant medications were not reported. Past drug history included: Symbicort for COPD, notes: an inhaled corticosteroid; Spiriva for COPD, notes: an inhaled muscarinic antagonist; Albuterol for COPD. Vaccination history included: Johnson & johnson covid-19 vaccine (11 months prior), for COVID-19 Immunization. The following information was reported: INTERCHANGE OF VACCINE PRODUCTS (hospitalization, medically significant, life threatening), outcome "unknown"; CHRONIC OBSTRUCTIVE PULMONARY DISEASE (hospitalization, medically significant, life threatening), 1 day after the suspect product(s) administration, outcome "unknown", described as "Chronic Obstructive Pulmonary Disease Exacerbation Following the Administration of a COVID 19-Booster Vaccine". The events "interchange of vaccine products" and "chronic obstructive pulmonary disease exacerbation following the administration of a covid 19-booster vaccine" required emergency room visit. The patient underwent the following laboratory tests and procedures: Adenovirus test: negative, notes: not detected; Basophil count: 0.1 %, notes: on admission; 0.1 %, notes: 1 day post admission; 0.3 %, notes: 2 days post admission; Basophil count: 0.0, notes: k/uL, on admission; 0.0, notes: k/uL, 1 day post admission; 0.0, notes: k/uL, 2 days post admission; Body temperature: 36.6 Centigrade, notes: afebrile; Bordetella test: negative, notes: not detected; Chest X-ray: demonstrated subtle patchy opacifications, notes: consistent with a COPD exacerbation, and no consolidations or pleural effusions. A normal cardiac silhouette was also observed; had no signs of infection an lacked any signs of, notes: pneumonia or infectious consolidations on chest x-ray; Coronavirus test: negative, notes: not detected; negative, notes: not detected; negative, notes: not detected; Negative, notes: Not detected; C-reactive protein: 58.49 mg/l, notes: elevated, 1 day post admission; Electrocardiogram: within normal limits; Eosinophil count: 1.7 %, notes: on admission; 0 %, notes: 1 day post admission; 2.8 %, notes: 2 days post admission; Eosinophil count: 0.2, notes: k/uL, on admission; 0.0, notes: k/uL, 1 day post admission; 0.2, notes: k/uL, 2 days post admission; Heart rate: 101, notes: beats per minute, upon arrival to ED; Human metapneumovirus test: negative, notes: not detected; Human rhinovirus test: negative, notes: not detected; Immature granulocyte count: 0.2 %, notes: on admission; 0.2 %, notes: 1 day post admission; 0.1 %, notes: 2 days post admission; Influenza A virus test: negative, notes: not detected; negative, notes: not detected; negative, notes: not detected; negative, notes: not detected; Negative, notes: Not detected; Influenza B virus test: negative, notes: not detected; Negative, notes: Not detected; Influenza virus test: negative, notes: not detected,; Negative, notes: Not detected; Negative, notes: Not detected; Negative, notes: Not detected; Negative, notes: Not detected; cardiac silhouette: normal; negative, notes: not detected; 0.02, notes: k/uL, on admission; 0.02, notes: k/uL, 1 day post admission; 0.01, notes: k/uL, 2 days post admission; Lymphocyte count: 22.9 %, notes: on admission; 11.4 %, notes: 1 day post admission; 19.1 %, notes: 2 days post admission; Lymphocyte count: 2.3, notes: k/uL, on admission; 1.0, notes: k/uL, 1 day post admission; 1.3, notes: k/uL, 2 days post admission; Monocyte count: 17.3 %, notes: on admission; 11 %, notes: 1 day post admission; 18 %, notes: 2 days post admission; Monocyte count: 1.7, notes: k/uL, on admission; 0.9, notes: k/uL, 1 day post admission; 1.2, notes: k/uL, 2 days post admission; Mycoplasma test: negative, notes: not detected; Myocardial necrosis marker: within normal limits; Neutrophil count: 57.8 %, notes: on admission; 77.3 %, notes: 1 day post admission; 59.7 %, notes: 2 days post admission; Neutrophil count: 5.8, notes: k/uL, on admission; 6.6, notes: k/uL, 1 day post admission; 4.0, notes: k/uL, 2 days post admission; Oxygen saturation: 95-88 %, notes: from baseline; 82 %, notes: upon arrival to ED,; hypoxic, notes: On arrival to the ED, patient was hypoxic requiring 3L of supplemental oxygen via nasal cannula; physical exam: patient was noted to be wheezing and breathing, notes: with difficulty; On discharge som emild wheezing was appreciated, notes: though decreased in severity; Red blood cell sedimentation rate: 73, notes: mm/hr, elevated, 1 day post admission; Respiratory syncytial virus test: negative, notes: not detected; negative, notes: not detected; Respiratory viral panel: negative, notes: common viral infections were ruled out; SARS-CoV-2 test: negative, notes: not detected; negative, notes: not detected; Sputum culture: after 3 days grew normal upper respiratory flora; White blood cell count: 10, notes: k/uL, on admission; 8.6, notes: k/uL, 1 day post admission; 6.8, notes: k/uL, 2 days post admission. Therapeutic measures were taken as a result of chronic obstructive pulmonary disease.Clinical course: The patient was presented to the Emergency Department (ED) complaining of shortness of breath and a cough producing white sputum for 2 days. The patients son had been monitoring her oxygen status, which showed a drop in her oxygen saturation (SpO2) from her baseline of 95%-88%, prompting him to bring her to the ED. Upon arrival the patient had an SpO2 of 82% and a heart rate of 101 beats per minute. Notably, she was afebrile, with a temperature of 36.6 C. On physical exam the patient was noted to be wheezing and breathing with difficulty. When questioned, the patient denied any fevers, chills, nausea, vomiting, diarrhea, or sore throat. She also denied any recent contactor exposures to someone with COVID-19. She stated that she does not smoke, nor does any one in her household, she was not exposed to any chemical fumes or burnt substances, and there are no pets in her home. There had been no new medications adjustments either. The only recent change that the patient or her son could identify was the administration of a Pfizer COVID19 booster vaccine one day before her symptoms began. Following her arrival to the ED, the patient was hypoxic requiring 3L of supplemental oxygen via nasal cannula. She was also prescribed prednisone, DuoNeb (ipratropium bromide/albuterol combination medication) and a onetime dose of doxycycline. Due to the severity of her symptoms, she was admitted to the hospital for further observation and provided with supplemental oxygen, 40 mg prednisone and DuoNeb daily, and her home medications. Throughout her hospital stay she remained afebrile. She was slowly weaned off supplemental oxygen over the course of her 5-day hospitalization. On discharge some mild wheezing was appreciated during a physical exam, the medical team recommended that she be evaluated by an outpatient pulmonologist to assess lung function, and she was sent home.; Sender's Comments: Based on the current available limited information in the case provided, the causal association between the events and the use of suspect product BNT162B2 cannot be fully 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.