Petechial rash on skin; Petechial hemorrhages in mouth/Blood spots in mouth; Immune thrombocytopenia; This spontaneous case was reported by a physician and describes the occurrence of IMMUNE THROMBOCYTOPENIA (Immune thrombocytopenia), PETECHIAE (Petechial rash on skin) and MOUTH HAEMORRHAGE (Petechial hemorrhages in mouth/Blood spots in mouth) in a 58-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination.    Co-suspect product included non-company product ROMIPLOSTIM (NPLATE) for Immune thrombocytopenic purpura.    The patient's past medical history included COVID-19 in 2020. Previously administered products included for Immune thrombocytopenia: Promacta, IGG and Danazol. Past adverse reactions to the above products included No adverse effect with Danazol, IGG and Promacta. Concurrent medical conditions included Immune thrombocytopenic purpura.   In 2012, the patient started ROMIPLOSTIM (NPLATE) (Subcutaneous) 500 microgram once a week. In May 2021, the patient received dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 04-Jun-2021, ROMIPLOSTIM (NPLATE) (Subcutaneous) dosage was changed to 500 microgram once a week. On 02-Jul-2021, ROMIPLOSTIM (NPLATE) (Subcutaneous) dosage was changed to 600 microgram once a week. On 30-Jul-2021, ROMIPLOSTIM (NPLATE) (Subcutaneous) dosage was changed to 700 microgram once a week. On 19-Aug-2021, ROMIPLOSTIM (NPLATE) (Subcutaneous) dosage was changed to 800 microgram once a week. On 17-Sep-2021, ROMIPLOSTIM (NPLATE) (Subcutaneous) dosage was changed to 900 microgram once a week. In May 2021, the patient experienced IMMUNE THROMBOCYTOPENIA (Immune thrombocytopenia) (seriousness criteria hospitalization and medically significant) and MOUTH HAEMORRHAGE (Petechial hemorrhages in mouth/Blood spots in mouth) (seriousness criteria hospitalization and medically significant). On 31-May-2021, the patient experienced PETECHIAE (Petechial rash on skin) (seriousness criteria hospitalization and medically significant). The patient was hospitalized from 04-May-2021 to 06-May-2021 due to IMMUNE THROMBOCYTOPENIA and MOUTH HAEMORRHAGE, and then from 31-May-2021 to 02-Jun-2021 due to PETECHIAE. The patient was treated with PREDNISONE for Salvage therapy, at an unspecified dose and frequency. At the time of the report, IMMUNE THROMBOCYTOPENIA (Immune thrombocytopenia) and PETECHIAE (Petechial rash on skin) was resolving and MOUTH HAEMORRHAGE (Petechial hemorrhages in mouth/Blood spots in mouth) had resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 06-May-2021, Platelet count: 600,000 (normal) 600,000. In May 2021, Platelet count: 14,000 (abnormal) 14,000 and 53,000. On 30-May-2021, Platelet count: 600,000 (normal) 600,000. On 31-May-2021, Platelet count: 8000 (abnormal) 8000. On 03-Jun-2021, Platelet count: 231,000 (normal) 231,000. On 10-Jun-2021, Platelet count: 261,000 (normal) 261,000. On 16-Jun-2021, Platelet count: elevated (High) Elevated, >200. On 17-Jun-2021, Platelet count: 84,000 (abnormal) 84,000. On 23-Jun-2021, Platelet count: 92,000 (abnormal) 92,000. On 02-Jul-2021, Platelet count: 64,000 (abnormal) 64,000. On 08-Jul-2021, Platelet count: 61,000 (abnormal) 61,000. On 15-Jul-2021, Platelet count: 91,000 (abnormal) 91,000. On 22-Jul-2021, Platelet count: 51,000 (abnormal) 51,000. On 29-Jul-2021, Platelet count: 36,000 (abnormal) 36,000. On 05-Aug-2021, Platelet count: 76,000 (abnormal) 76,000. On 12-Aug-2021, Platelet count: 45,000 (abnormal) 45,000. On 18-Aug-2021, Platelet count: 36,000 (abnormal) 36,000. On 27-Aug-2021, Platelet count: 67,000 (abnormal) 67,000. On 02-Sep-2021, Platelet count: 56,000 (abnormal) 56,000. On 09-Sep-2021, Platelet count: 50,000 (abnormal) 50,000. On 14-Sep-2021, Full blood count: 14000 (abnormal) 14000. On 15-Sep-2021, Platelet count: 18,000 (abnormal) 18,000. On 16-Sep-2021, Platelet count: 49,000 (abnormal) 49,000. On 23-Sep-2021, Platelet count: 106,000 (abnormal) 106,000. On 28-Sep-2021, Platelet count: 73,000 (abnormal) 73,000. On 18-Nov-2021, Antibody test: negative (Negative) Negative. On 18-Nov-2021, Drug specific antibody: negative (Negative) Negative and negative (Negative) Negative.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter considered IMMUNE THROMBOCYTOPENIA (Immune thrombocytopenia) to be related. No further causality assessments were provided for PETECHIAE (Petechial rash on skin) and MOUTH HAEMORRHAGE (Petechial hemorrhages in mouth/Blood spots in mouth).    No concomitant therapy data provided.  Patient was hospitalized from 04-May-2021 to 06may2021 due to reduced platelet count and petechial hemorrhages in mouth. On an unknown date, treatment included Prednisone, which was administered on first hospitalization, on 15-SEP-2021, platelets were 18,000 and therefore Prednisone rescue therapy was started on 15-SEP-2021 and did a prednisone taper.   Post administration of Nplate, patient had 80 immune thrombocytopenia exacerbations throughout the treatment with Nplate.  Company comment: This case concerns a 58-year-old male patient with medical history of immune thrombocytopenic purpura, who experienced the unexpected, serious (hospitalization) events of immune thrombocytopenia, petechiae and mouth haemorrhage. The events occurred an unknown time after a dose of mRNA-1273. The medical history of immune thrombocytopenia purpura is a confounding factor. Hospitalization lasted 2 days. Treatment included prednisone taper which improved platelet count from 14,000 to 600,000. Previously, the patient refers having 79 episodes of immune thrombocytopenia flares caused by infections such as influenza, viral bronchitis, and COVID-19. The benefit-risk relationship of mRNA-1273 is not affected by this report.; Sender's Comments: This case concerns a 58-year-old male patient with medical history of immune thrombocytopenic purpura, who experienced the unexpected, serious (hospitalization) events of immune thrombocytopenia, petechiae and mouth haemorrhage. The events occurred an unknown time after a dose of mRNA-1273. The medical history of immune thrombocytopenia purpura is a confounding factor. Hospitalization lasted 2 days. Treatment included prednisone taper which improved platelet count from 14,000 to 600,000. Previously, the patient refers having 79 episodes of immune thrombocytopenia flares caused by infections such as influenza, viral bronchitis, and COVID-19. The benefit-risk relationship of mRNA-1273 is not affected by this report.