Thrombotic thrombocytopenic purpura; This literature-non-study case was reported in a literature article and describes the occurrence of THROMBOTIC THROMBOCYTOPENIC PURPURA (Thrombotic thrombocytopenic purpura) in an elderly female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination.       Concurrent medical conditions included Chronic myeloid leukaemia (Patient has a history of chronic myeloid leukaemia (CML), diagnosed 5 years prior. CML is being treated with dasatinib, and patient is currently in molecular remission.) since 2017, Hyperlipidemia and Tobacco user. Concomitant products included DASATINIB for Chronic myeloid leukaemia.   On an unknown date, the patient received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On an unknown date, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form and first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On an unknown date,  after starting mRNA-1273 (Moderna COVID-19 Vaccine), the patient experienced THROMBOTIC THROMBOCYTOPENIC PURPURA (Thrombotic thrombocytopenic purpura) (seriousness criteria hospitalization and medically significant). The patient was treated with METHYLPREDNISOLONE for Thrombotic thrombocytopenic purpura, at a dose of 250 milligram every six hours. At the time of the report, THROMBOTIC THROMBOCYTOPENIC PURPURA (Thrombotic thrombocytopenic purpura) had resolved. Related    DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): In 2018, Biopsy bone marrow: negative for clonal plasma Bone marrow biopsy was negative for clonal plasma cells. In 2018, Haemoglobin (121-150): 15.3 g/dl The most recent blood count 4 years prior showed a haemoglobin of 15.3 g/dL. In 2018, Platelet count (150-400): 312 bil/l (normal) The most recent blood count 4 years prior showed a platelet count of 312 bil/L. On an unknown date, ADAMTS13 activity assay (Unknown->/=70%): 7% (Low) ADAMTS13 level returned at 7%. On an unknown date, ADAMTS13 inhibitor screen assay: negative (Negative) testing was negative for an ADAMTS13 inhibitor.. On an unknown date, Biopsy bone marrow: adequate trilineage haematopoiesi Bone marrow examination of the left iliac crest showed normocellular bone marrow with adequate trilineage haematopoiesis. No overt evidence of marrow involvement by chronic myeloid leukaemia, lymphoma or metastatic malignancy was identified. Severe normocytic anaemia with schistocytes and severe thrombocytopenia were seen, which was consistent with microangiopathic haemolytic anaemia. These findings were consistent with TTP. On an unknown date, Blood creatinine (0.50-1.10): 0.98 mg/dl (normal) 0.98 mg/dL. On an unknown date, Blood fibrinogen (200-400): 444 mg/dl (High) 444 mg/dL. On an unknown date, Blood immunoglobulin A (70-365): 69 mg/dll (Low) IgA was 69 mg/dL. On an unknown date, Blood immunoglobulin G: normal limits (normal) IgG was within normal limits. On an unknown date, Blood immunoglobulin M: normal limits (normal) IgM was within normal limits. On an unknown date, Blood lactate dehydrogenase (100-240): 1381 u/l (High) 1381 U/L. On an unknown date, C-reactive protein (Unknown-<8.0): 28.2 mg/l (High) 28.2 mg/L. On an unknown date, Capillary nail refill test: 23 s prolonged capillary refill at 23 s. On an unknown date, Computerised tomogram head: negative (Negative) CT head was ordered to rule out intracranial bleed, which was negative.. On an unknown date, Coombs test: negative (Negative) negative. On an unknown date, Fibrin D dimer (Unknown-0/499 ng/ml): 5838 ng/ml feu (High) 5838 ng/mL FEU. On an unknown date, Flow cytometry: no evidence of a paroxysmal nocturnal haemoglobin Flow cytometric analysis showed no evidence of a paroxysmal nocturnal haemoglobinuria clone based on analysis of glycosylphosphatidylinositol-linked antibodies.. On an unknown date, Glomerular filtration rate (Unknown->60 ml/min/1.73 m^2): 58 ml/min/1.73 m^2 (Low) 58 mL/min/1.73 m^2. On an unknown date, HIV antigen: non-reactive HIV-1 p24 antigen/HIV-½ antibody screen was non-reactive.. On an unknown date, Haemoglobin (121-150): 78g/l (Low) 78g/L. On an unknown date, Haptoglobin (40-250): less than 8mg/dl (Low) less than 8mg/dL. On an unknown date, Heparin-induced thrombocytopenia test positive (Unknown-<0.400 od): 0.050 od 0.050 OD. On an unknown date, Light chain analysis (0.33-1.94): 5.02 mg/dl (High) Free kappa was slightly elevated at 5.02 mg/dL, 3.44 (High) Free kappa/lambda ratio was elevated at 3.44 and 1.46 mg/dl (normal) free lambda was normal at 1.46 mg/dL. On an unknown date, Physical examination: pertinent only for wheezing Physical exam was pertinent only for wheezing bilaterally on lung exam. There were no gross ecchymoses or petechiae and platelets recovered With initiation of the above treatments, the platelets recovered quickly, increasing to 23 bil/L, followed by 135 bil/L.. On an unknown date, Platelet count (150-400): 10 bil/l (Low) 10 bil/L, platelets recovered With initiation of the above treatments, the platelets recovered quickly, increasing to 23 bil/L, followed by 135 bil/L., 150 bil/l On treatment, the platelet count had recovered to greater than 150 bil/L. and normal range (normal) Platelet count was back to the normal range by the fourth day of treatment.. On an unknown date, Protein total (6.2-8.1): 5.8 g/dl (Low) Monoclonal gammopathy evaluation was only significant for a slightly low total protein level of 5.8 g/dL. No monoclonal proteins were detected. On an unknown date, Red blood cell schistocytes (Unknown-<1, absent): about 35/hpf schistocytes about 35/HPF (normal <1, absent). On an unknown date, Red blood cell sedimentation rate (0-18): 46 mm/hour (High) 46 mm/hour. On an unknown date, Renal function test: nornal Renal function was normal. On an unknown date, SARS-CoV-2 test: negative (Negative) COVID-19 testing was negative. On an unknown date, Urine analysis: significant for 3+blood (abnormal) Urinalysis was significant for 3+blood (normal=absent).. On an unknown date, Vital signs measurement: normal limits (normal) On admission, all vitals were within normal limits. On an unknown date, White blood cell count (3.3-10.7): 7.7 bil/l (normal) 7.7 bil/L.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter considered THROMBOTIC THROMBOCYTOPENIC PURPURA (Thrombotic thrombocytopenic purpura) to be related.    Patient began to develop symptoms 2 days after receiving her Moderna booster vaccine and presented to urgent care with an 8 day history of fatigue, generalised weakness, headache, abdominal pain and haematuria.  Patient was asymptomatic following her first 2 Moderna vaccines. There were no recent medication changes.  Pathologist review of the blood sample showed marked thrombocytopenia,  worrisome for thrombotic microangiopathy. Therefore, further workup was ordered stat.  Genetic testing for congenital TTP was not completed on the patient.  Treatment also included therapeutic plasma exchange which was ordered and initiated within 24 hours of admission after a central line was placed by interventional radiology. She underwent daily therapeutic plasma exchange with 100% plasma volume replacement with 4000 mL of fresh frozen plasma. She completed daily exchanges for 4 days, and then these were stopped.  Three days after treatment was initiated with steroids and plasmapheresis, the diagnosis of TTP was confirmed  The patient recovered well and continues to follow with her haematologist.  Patient had laboratory findings suggesting TTP including: severe thrombocytopenia, microangiopathic anaemia with elevated haemolytic markers, the presence of schistocytes in peripheral blood, and low ADAMTS13 activity, along with typical clinical symptoms. Her PLASMIC score was 7 indicating severe disease, and she also had a negative PF4 antibody arguing against VITT. As completed in our patient, urgent plasmapheresis is the cornerstone of TTP management and should be implemented at the time of suspicion.  The temporal relationship to receiving the Moderna vaccine and development of TTP makes the vaccine more likely the culprit. However, there is no way to prove the vaccine was the cause of TTP and a causal association cannot be established based on a single case. Company comment: This literature-non-study case concerns an elderly female patient.  This literature-non-study case concerns an elderly female patient with relevant Concurrent medical conditions of Chronic myeloid leukaemia (since 5 years) and being treated with dasatinib, and patient is currently in molecular remission (since 2017, who experienced the unexpected, serious ADR event of THROMBOTIC THROMBOCYTOPENIC PURPURA (hospitalization and medically significant) after receiving the unspecified dose of the mRNA-1273 vaccine on an unspecified date. The symptoms developed 2 days after receiving Moderna booster vaccine and presented to urgent care 8 days after receiving it. Patient was asymptomatic after the first 2 Moderna vaccines. There were no recent medication changes and on dasatinib for years. On admission, all vitals were within normal limits. There were no gross ecchymoses or petechiae. COVID-19 testing was negative. laboratory findings suggesting TTP including severe thrombocytopenia, microangiopathic anemia with elevated hemolytic markers, the presence of schistocytes in peripheral blood, and low ADAMTS13 activity, along with typical clinical symptoms. Her PLASMIC score was 7 indicating severe disease, and she also had a negative PF4 antibody arguing against VITT. Additional treatment includes corticosteroids and rituximab. Patient's concurrent condition of CML remains a confounder. The benefit-risk relationship of the mRNA-1273 vaccine is not affected by this report.   Most recent FOLLOW-UP information incorporated above includes: On 12-May-2022: Live follow-up received by safety on 12-MAY-2022 has Email received from a medical team and contains significant information. Reporter information, citation details, patient information (gender, age group), medical history, laboratory data, concomitant drugs, treatment drugs, seriousness criteria of hospitalization and outcome of event updated.; Sender's Comments: This literature-non-study case concerns an elderly female patient with relevant Concurrent medical conditions of Chronic myeloid leukaemia (since 5 years) and being treated with dasatinib, and patient is currently in molecular remission (since 2017, who experienced the unexpected, serious ADR event of THROMBOTIC THROMBOCYTOPENIC PURPURA (hospitalization and medically significant) after receiving the unspecified dose of the mRNA-1273 vaccine on an unspecified date. The symptoms developed 2 days after receiving Moderna booster vaccine and presented to urgent care 8 days after receiving it. Patient was asymptomatic after the first 2 Moderna vaccines. There were no recent medication changes and on dasatinib for years. On admission, all vitals were within normal limits. There were no gross ecchymoses or petechiae. COVID-19 testing was negative. laboratory findings suggesting TTP including severe thrombocytopenia, microangiopathic anemia with elevated hemolytic markers, the presence of schistocytes in peripheral blood, and low ADAMTS13 activity, along with typical clinical symptoms. Her PLASMIC score was 7 indicating severe disease, and she also had a negative PF4 antibody arguing against VITT. Additional treatment includes corticosteroids and rituximab. Patient's concurrent condition of CML remains a confounder. The benefit-risk relationship of the mRNA-1273 vaccine is not affected by this report.