platelet counts were low; lost 5 lbs; Angry, hurt; tired; This spontaneous case was reported by a consumer and describes the occurrence of PLATELET COUNT DECREASED (platelet counts were low) in a 67-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 021B21A and 031M20A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     Concurrent medical conditions included Type 1 diabetes mellitus and Blood pressure high. Concomitant products included INSULIN for an unknown indication.   On 11-Mar-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 08-Apr-2021, 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 PLATELET COUNT DECREASED (platelet counts were low) (seriousness criterion hospitalization), WEIGHT DECREASED (lost 5 lbs), FEELING ABNORMAL (Angry, hurt) and FATIGUE (tired). The patient was hospitalized for 5 days due to PLATELET COUNT DECREASED. The patient was treated with AVATROMBOPAG MALEATE (DOPTELET) for Platelets decreased, at an unspecified dose and frequency. At the time of the report, PLATELET COUNT DECREASED (platelet counts were low), WEIGHT DECREASED (lost 5 lbs), FEELING ABNORMAL (Angry, hurt) and FATIGUE (tired) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Blood test: normal (normal) had blood work done one month before and it was fine. On an unknown date, Platelet count: low (Low) platelet counts were low between 8,000 and 9,000. On an unknown date, Weight decreased: low (Low) lost 5 lbs.         Additional concomitant medication includes low dose blood pressure medicine and cholesterol medication. Treatment medications includes Treatment Steroids, IVIG Therapy.Two weeks after the second dose,  she experienced some bruising on the sides of legs and waist, abdomen and arms. She reported that she went to her doctor and blood work was performed.  Her platelet counts were low between 8,000 and 9,000. Patient reported that she stayed in the hospital for 5 days on Memorial Day weekend and was given steroids and IVIG therapy. The caller reported it brought her platelets up for 2 weeks, but the steroids affected her sugar levels. After two weeks her platelets dropped again. She was given steroid again and IVIG therapy as outpatient. A couple of weeks later her platelets dropped again and she was placed on Doptelet by a hematologist. On unknown date in Apr 2021, the patient experienced bruising on the sides of legs/bruising on the waist/bruising on the abdomen/bruising on the arms. Company comment: This case concerns a 67 year-old, female patient with a history of Type 1 diabetes mellitus, who experienced the serious (due to hospitalization) unexpected AESI of Platelet count decreased. The event occurred after the second dose of Moderna COVID-19 vaccine, exact date not provided. The rechallenge was not applicable, as the event was reported exclusively after the second dose. The patient was hospitalized for 5 days and treated with steroids and intravenous immunoglobulins therapy. The medical history, of Type 1 diabetes mellitus, remain a confounder. The benefit-risk relationship of Moderna COVID-19 vaccine is not affected by this report.   Most recent FOLLOW-UP information incorporated above includes: On 02-Nov-2021: Significant Follow-up received - Patient demographics, medical history, lab test details, suspect product dose details, concomitant medication details updated and new serious events platelet count low, illness, bruising, weight loss, feeling abnormal and fatigue added and case upgraded to serious.; Sender's Comments: This case concerns a 67 year-old, female patient with a history of Type 1 diabetes mellitus, who experienced the serious (due to hospitalization) unexpected AESI of Platelet count decreased. The event occurred after the second dose of Moderna COVID-19 vaccine, exact date not provided. The rechallenge was not applicable, as the event was reported exclusively after the second dose. The patient was hospitalized for 5 days and treated with steroids and intravenous immunoglobulins therapy. The medical history, of Type 1 diabetes mellitus, remain a confounder. The benefit-risk relationship of Moderna COVID-19 vaccine is not affected by this report.