Approximately 13 hours after receiving dose 1 her platelet count fell; Exacerbation of preexisting ITP can sequentially increase in severity with each of the 2 doses; This literature-non-study case was reported in a literature article and describes the occurrence of IMMUNE THROMBOCYTOPENIA (Approximately 13 hours after receiving dose 1 her platelet count fell) in a 72-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.    Concurrent medical conditions included Immune thrombocytopenia. Concomitant products included ELTROMBOPAG for Immune thrombocytopenia.   On an unknown date, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On an unknown date, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On an unknown date, the patient experienced IMMUNE THROMBOCYTOPENIA (Approximately 13 hours after receiving dose 1 her platelet count fell) (seriousness criterion medically significant) and CONDITION AGGRAVATED (Exacerbation of preexisting ITP can sequentially increase in severity with each of the 2 doses). The patient was treated with ELTROMBOPAG for Adverse event, at a dose of 50 milligram once a day and ELTROMBOPAG for Adverse event, at a dose of 75 milligram once a day. At the time of the report, IMMUNE THROMBOCYTOPENIA (Approximately 13 hours after receiving dose 1 her platelet count fell) and CONDITION AGGRAVATED (Exacerbation of preexisting ITP can sequentially increase in severity with each of the 2 doses) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): In 2021, Platelet count: 65-80 10^9/L (Inconclusive) before dose 1 of Moderna SARS-CoV-2 vaccine, 45 10^9/L (Low) Approximately 13 hours after receiving dose 1 of the Moderna SARS-CoV-2 vaccine platelet count fell to 45 x10^9/L.(42% decrease), 298 10^9/L (High) After eltrombopag dose was increased to 50 mg daily with an increase in platelet count to a peak of 298 x 3 10^9/L., 193 10^9/L (Inconclusive) Approximately 1 hour before receiving dose 2, the platelet count was 193 x 10^9/L and 205 10^9/L (High) In response to 3 doses, the platelet count increased to 205 x10^9/L. In 2021, SARS-CoV-2 antibody test: negative (Negative) Negative.     mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosing remained unchanged.   For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter considered IMMUNE THROMBOCYTOPENIA (Approximately 13 hours after receiving dose 1 her platelet count fell) and CONDITION AGGRAVATED (Exacerbation of preexisting ITP can sequentially increase in severity with each of the 2 doses) to be possibly related.    It was reported that the eltrombopag daily dose was adjusted to compensate for dynamic platelet destruction. The platelet count fell to 42% with the first, consistent with a cumulative effect on the underlying humoral response.  Although the patient has a history of chronic ITP, based on a strong relationship as the event is reported to have an onset latency of 13 hours after administration of mRNA-1273, a causal relationship between the product use and the event cannot be excluded. Some vaccines have been shown to be associated with both reactivation of immune mediated diseases such as immune thrombocytopenia purpura   This case was linked to MOD-2021-263965, MOD-2021-263970, MOD-2021-264203 (Patient Link).; Sender's Comments: Although the patient has a history of chronic ITP, based on a strong relationship as the event is reported to have an onset latency of 13 hours after administration of mRNA-1273, a causal relationship between the product use and the event cannot be excluded. Some vaccines have been shown to be associated with both reactivation of immune mediated diseases such as immune thrombocytopenia purpura