The patient developed  recurrent thrombocytopaenia; This is a literature report for the following literature source(s): Regulatory Authority.  A female patient in her 50's received BNT162b2 (BNT162B2), as dose 2, single (Batch/Lot number: unknown) for covid-19 immunisation. The patient's relevant medical history included: "Immune thrombocytopaenic purpura" (unspecified if ongoing); "ecchymoses" (unspecified if ongoing), notes: atraumatic, bilateral upper and lower extremity ecchymoses; "pulmonary embolism" (unspecified if ongoing). The patient's concomitant medications were not reported. Vaccination history included: Covid-19 vaccine (Dose 1,Single). The following information was reported: THROMBOCYTOPENIA (medically significant, life threatening), outcome "recovered", described as "The patient developed  recurrent thrombocytopaenia". The patient underwent the following laboratory tests and procedures: Alanine aminotransferase: 20, notes: Day 8; Arteriogram: pulmonary embolism; Aspartate aminotransferase: 21, notes: Day 8 07:00 hours; Blood alkaline phosphatase: 100, notes: Day 8 07:00 hours; Blood bilirubin: 1.3 mg/dl, notes: Day 8 07:00 hours; 0.7 mg/dl, notes: Day 8 19:00 hours; 0.6 mg/dl, notes: Day 47; Blood fibrinogen: 287 mg/dl, notes: Day 8 19:00 hours; 377 mg/dl, notes: Day 47; Blood lactate dehydrogenase: 210, notes: Day 8 19:00 hours; 217, notes: day 47; Fibrin D dimer: 1.64 mg/l, notes: Day 8 19:00 hours; 0.21 mg/l, notes: day 47; Hemoglobin: 14.5 dL, notes: Day 8, 7:00 hrs; 13.8 dL, notes: Day 8, 19:00 hrs; 12.8 dL, notes: Day 9; 13.4 dL, notes: Day 10; 14.5 dL, notes: day 16; 14.1 dL, notes: day 33; 14.2 dL, notes: Day 47; 14.5 dL, notes: Day 48; 12.9 dL, notes: Day 49; 14.3 dL, notes: 1 year later; Haptoglobin: 59 mg/dl, notes: Day 8 19:00 hours; 72 mg/dl, notes: day 47; International normalized ratio: 1.0, notes: Day 8 19:00 hours; Mean platelet volume: 12.1; 14.7; 12.9; 11.2; 13.7; 13.2; 12.1; Physical examination: Unremarkable; Platelet count: 21000 /mm3; 255000 /mm3; 3000 /mm3; 55000 /mm3; 101 000 /mm3; 7000 /mm3; 214 000 /mm3; 190 000 to 2 50 000; Prothrombin level: 24.5, notes: Day 8 19:00 hours; 27.3, notes: day 47; Prothrombin time: 10.4 seconds, notes: Day 8 19:00 hours; 10.1 seconds, notes: Day 47; SARS-CoV-2 test: Negative, notes: Day 8 19:00 hours; Smear test: giant platelets; Ultrasound Doppler: negative for thrombosis; Vitamin B12: 1466 pg/mL, notes: Day 8 19:00 hours; White blood cell count: 6.2 /mm3, notes: Day 8 07:00 hours; 8.5 /mm3, notes: Day 8 19:00 hours; 7.8 /mm3, notes: Day 9; 6.1 /mm3, notes: Day 10; 9.1 /mm3, notes: Day 16; 8.9 /mm3, notes: Day 33; 11.10 /mm3, notes: Day 47; 7.9 /mm3, notes: Day 48; 5.6 /mm3, notes: Day 49; 5.8 /mm3, notes: 1 year later. Therapeutic measures were taken as a result of thrombocytopenia.; Sender's Comments: Based on the information provided in the narrative, a causal association between the event and the suspect drug 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.