doctors told her probably she was immunocompromised due to the vaccine; experiencing ulcers or blisters in her mouth/blisters came back really bad; tongue and cheeks; blisters in her mouth, tongue; blisters in her mouth, tongue; ulcers were bleeding; This spontaneous case was reported by a consumer and describes the occurrence of ULCER HAEMORRHAGE (ulcers were bleeding) and IMMUNODEFICIENCY (doctors told her probably she was immunocompromised due to the vaccine) in a 72-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 002M21A, 020F21A and 011H21A) for COVID-19 prophylaxis. The occurrence of additional non-serious events is detailed below.     Question:Describe relevant medical history/conditions, allergy, concomitant diseases and risk factor.Answer:achalasia, recently her rheumatologist told her that the immune system could be compromised.  The patient's past medical history included Achalasia. Concurrent medical conditions included Immune imbalance (recently her rheumatologist told her that the immune system could be compromised).   On 05-Feb-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 07-Feb-2021, received fourth dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 05-Mar-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 22-Oct-2021, received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 07-May-2022, received fifth dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 17-May-2022, the patient experienced ULCER HAEMORRHAGE (ulcers were bleeding) (seriousness criterion medically significant), MOUTH ULCERATION (experiencing ulcers or blisters in her mouth/blisters came back really bad), TONGUE ULCERATION (tongue and cheeks), TONGUE BLISTERING (blisters in her mouth, tongue) and ORAL MUCOSAL BLISTERING (blisters in her mouth, tongue). On an unknown date, the patient experienced IMMUNODEFICIENCY (doctors told her probably she was immunocompromised due to the vaccine) (seriousness criterion medically significant). The patient was treated with PREDNISONE at an unspecified dose and frequency; PREDNISONE at an unspecified dose and frequency; PREDNISONE at an unspecified dose and frequency and PROCAINE (NOVOCAINE [PROCAINE]) at an unspecified dose and frequency. At the time of the report, ULCER HAEMORRHAGE (ulcers were bleeding), IMMUNODEFICIENCY (doctors told her probably she was immunocompromised due to the vaccine), MOUTH ULCERATION (experiencing ulcers or blisters in her mouth/blisters came back really bad) and TONGUE ULCERATION (tongue and cheeks) was resolving and TONGUE BLISTERING (blisters in her mouth, tongue) and ORAL MUCOSAL BLISTERING (blisters in her mouth, tongue) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Computerised tomogram: Negative.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments.   No concomitant medications were reported. The patient did not receive any other vaccines in the 4 weeks prior to COVID-19. It was reported that after 1st and 3 doses patient did not experienced any symptoms. The patient went to the dermatologist and they prescribed Prednisone, it got better but a couple months later blisters came back really bad and she went to the dermatologist again and the rheumatologist, doctors prescribed antibiotics and antiviral treatment but it did not work, they prescribed another 2 rounds of Prednisone plus antiviral and antibiotic, rheumatologist told her she probably experienced this reaction due to Moderna COVID-19 Vaccine. On 19-Aug-2022 the day after she got another appointment with her dermatologist and they prescribed Novocaine it started going really bad again, and the doctors told her probably she was immunocompromised due to the vaccine.  Company comment: This spontaneous case concerns a 72-year-old, female patient with relevant medical history of immune imbalance, who experienced the serious (medically significant) unexpected events of Ulcer haemorrhage after about 10 days and Immunodeficiency which occurred unknown days after administration of fifth dose of mRNA-1273 vaccine. She experienced ulcers or blisters in her mouth, tongue and cheeks and ulcers were bleeding. She received prednisolone for treatment and symptoms got better but recurred after about 2 months. Then she received prednisone plus antiviral and antibiotic (unspecified) for treatment. A CT scan was done to search for cancer, but it came negative. Doctors told her probably she was immunocompromised due to the vaccine. The event was resolving at the time of the report. Medical history of immune imbalance remains confounding for the events. The benefit-risk relationship of mRNA- 1273 vaccine is not affected by this report.