Active IgA nephropathy; Gross hematuria; This case was reported in a literature article and describes the occurrence of IGA NEPHROPATHY (Active IgA nephropathy) in a 50-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 Hypertension, Antiphospholipid syndrome and Obesity. Concomitant products included AMLODIPINE, FUROSEMIDE, OLMESARTAN, WARFARIN and ENOXAPARIN for an unknown indication.   On an unknown date, the patient received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On an unknown date, received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On an unknown date, the patient experienced IGA NEPHROPATHY (Active IgA nephropathy) (seriousness criterion medically significant) and HAEMATURIA (Gross hematuria). At the time of the report, IGA NEPHROPATHY (Active IgA nephropathy) outcome was unknown and HAEMATURIA (Gross hematuria) had resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): In 2021, Antibody test: negative (Negative) negative. In 2021, Antineutrophil cytoplasmic antibody: negative (Negative) negative. In 2021, Antinuclear antibody: negative (Negative) negative. In 2021, Biopsy: abnormal (abnormal) IgA nephropathy among 12 glomeruli samples, 3 were globally sclerotic and 1 contained a segmental scar. The remainder had mild diffuse mesangial hypercellularity and 1 glomerulus displayed active segmental fibrinoid necrosis with mild leukocyte infiltration, rupture of glomerular basement membrane and an overlying segmental cellular crescent. their was 30% tubulointerstitial scarring and moderate arterio- and arteriosclerosis.. In 2021, Blood creatinine: 1.7 (High) 1.7 mg/dl. In 2021, Complement factor C3: negative (Negative) negative. In 2021, Complement factor C4: negative (Negative) negative. In 2021, Hepatitis B surface antigen: negative (Negative) negative. In 2021, Hepatitis C antibody: negative (Negative) negative. In 2021, IgA nephropathy: abnormal (abnormal) M1E0S1T1C1. In 2021, Immunology test: positive (Positive) global granular mesangial staining for IgA (3+), C3 (1+), kappa (2-3+), and lambda (3+). In 2021, Urine analysis: >50 (High) red blood cells per high-power field, baseline of 10-20 rbcs 7 months prior to presentation. In 2021, Urine protein/creatinine ratio: 2 (High) g/g; baseline values of 1.3mg/dl and 1.3g/g 7 months prior to presentation.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter considered IGA NEPHROPATHY (Active IgA nephropathy) and HAEMATURIA (Gross hematuria) to be possibly related.    Treatment medication not provided. Follow up received by safety on 8-Jul-21 contains no new information. Based on the current available information and temporal association between the use of the product and the start date of the events, a causal relationship cannot be excluded.   This case was linked to MOD-2021-249638, MOD-2021-249639 (Patient Link).   Most recent FOLLOW-UP information incorporated above includes: On 07-Jul-2021: Full text article received; Sender's Comments: Based on the current available information and temporal association between the use of the product and the start date of the events, a causal relationship cannot be excluded.