Symptoms from Chron's/ Crohn's disease flare up; Tightness in lower abdomen/gurgling; Tightness in lower abdomen/gurgling; Bloating; Inflammed; Cramps; This spontaneous case was reported by a consumer and describes the occurrence of CROHN'S DISEASE (Symptoms from Chron's/ Crohn's disease flare up) in a 28-year-old male patient who received mRNA-1273 (Spikevax) (batch no. 027L21A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.    Co-suspect product included non-company product ADALIMUMAB (HUMIRA) for Crohn's disease.    The patient's past medical history included Ex-tobacco user (A pack of cigarette per week or every two weeks) from 2019 to January 2022 and COVID-19 (COVID-19 positive) in January 2022. Concurrent medical conditions included Crohn's disease (Moderate to severe adult Crohn's disease), Abstains from alcohol, Peanut allergy (manifested by moderate to severe break out in hives), Allergy to nuts (manifested by moderate to severe outbreak in hives), Pollen allergy (skin and respiratory related), Airway secretion excessive since January 2022, Chest pain since January 2022, Back pain since January 2022, Vitamin D decreased since December 2021 and Blood iron decreased since December 2021.   In June 2020, the patient started ADALIMUMAB (HUMIRA) (Subcutaneous) 1 dosage form. On 17-Feb-2022, the patient received first dose of mRNA-1273 (Spikevax) (Intramuscular) 1 dosage form. In February 2022, the patient experienced CROHN'S DISEASE (Symptoms from Chron's/ Crohn's disease flare up) (seriousness criterion medically significant), GASTROINTESTINAL SOUNDS ABNORMAL (Tightness in lower abdomen/gurgling), ABDOMINAL RIGIDITY (Tightness in lower abdomen/gurgling), ABDOMINAL DISTENSION (Bloating), INFLAMMATION (Inflammed) and MUSCLE SPASMS (Cramps). The patient was treated with PREDNISONE at an unspecified dose and frequency. At the time of the report, CROHN'S DISEASE (Symptoms from Chron's/ Crohn's disease flare up), GASTROINTESTINAL SOUNDS ABNORMAL (Tightness in lower abdomen/gurgling), ABDOMINAL RIGIDITY (Tightness in lower abdomen/gurgling), ABDOMINAL DISTENSION (Bloating) and INFLAMMATION (Inflammed) was resolving and MUSCLE SPASMS (Cramps) outcome was unknown.        The action taken with mRNA-1273 (Spikevax) (Intramuscular) was unknown.    Company comment : This spontaneous case concerns a 28-year-old, male patient with relevant medical history of Moderate-to-severe Crohn's disease previously treated with the co-suspect product Humira (adalimumab) which was discontinued in Feb2021, who experienced the unexpected, serious (medically significant) event of Crohn's disease (Crohn's disease aggravated) and other unexpected, non-serious events. The events occurred unknown number of days after receiving the first dose of the mRNA-1273 vaccine. Of note, the onset dates were reported as unspecified dates in Feb2022, hence, the onset latency could not be assessed. It was reported that the patient experienced tightness in the lower abdomen with gurgling, bloating, symptoms of Crohn's disease flare-up (bloody stools), inflammation and cramps. The patient was treated with prednisone (unspecified dose, frequency and duration). The reporter stated that the alternative etiology for the patient's symptoms was due to being off of Humira. The medical history of Crohn's disease remains a confounder for the event Crohn's disease aggravated since waxing and waning of symptoms is part of the natural course of the disease. The discontinuation of Humira also remains a confounder. The benefit-risk relationship of the mRNA-1273 vaccine is not affected by this report.   No concomitant medication was reported.  The reporter alternate etiology for events of cramping, bloating, gurgling, tightness in lower abdomen and bloody stools were reported as off Humira and for the events of chest pain and chest with mucus were reported as after stopped smoking.  It was unknown if patient was enrolled in a COVID-19 vaccine trial.  The reporter's causality for the events of tightness in lower abdomen/gurgling, bloating, symptoms from Crohn's/ Crohn's disease flare up, inflamed and cramps with Humira (adalimumab) was no reasonable possibility.  Patient had some lab data: BONE DENSITY SCAN -  ??-Dec-2021 COVID-19 ANTIBODY SWAB TEST - ??-Jan-2022 IRON -  ??-Dec-2021 STOOL TEST -  ??-Dec-2021 VITAMIN D - ??-Dec-2021   This case was identified as part of a retrospective clean-up activity where certain emails received in the Moderna mailbox were missed to be booked-in.   Most recent FOLLOW-UP information incorporated above includes: On 10-Aug-2022: Follow-up received: Event "cramp" was added. Update product dose no, Current condition added and lab data removed inarrative supplement updated.; Sender's Comments: This spontaneous case concerns a 28-year-old, male patient with relevant medical history of Moderate-to-severe Crohn's disease previously treated with the co-suspect product Humira (adalimumab) which was discontinued in Feb2021, who experienced the unexpected, serious (medically significant) event of Crohn's disease (Crohn's disease aggravated) and other unexpected, non-serious events. The events occurred unknown number of days after receiving the first dose of the mRNA-1273 vaccine. Of note, the onset dates were reported as unspecified dates in Feb2022, hence, the onset latency could not be assessed. It was reported that the patient experienced tightness in the lower abdomen with gurgling, bloating, symptoms of Crohn's disease flare-up (bloody stools), inflammation and cramps. The patient was treated with prednisone (unspecified dose, frequency and duration). The reporter stated that the alternative etiology for the patient's symptoms was due to being off of Humira. The medical history of Crohn's disease remains a confounder for the event Crohn's disease aggravated since waxing and waning of symptoms is part of the natural course of the disease. The discontinuation of Humira also remains a confounder. The benefit-risk relationship of the mRNA-1273 vaccine is not affected by this report.