admitted for further management of a PNH flare; severe hemolysis; heme pigment-associated acute kidney injury; Condition aggravated; Approximately 8 hours after receiving dose 2 she developed Flu-like symptoms; One day after dose 2, she developed dark urine; One day after dose 2, she developed generalized weakness; One day after dose 2, she developed abdominal pain; One day after dose 2, she developed odynophagia; This literature-non-study case was reported in a literature article and describes the occurrence of PAROXYSMAL NOCTURNAL HAEMOGLOBINURIA (admitted for further management of a PNH flare), ACUTE KIDNEY INJURY (heme pigment-associated acute kidney injury), HAEMOLYSIS (severe hemolysis), and CONDITION AGGRAVATED (Condition aggravated) in an 81-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.   LITERATURE REFERENCE: Autoimmune- and complement-mediated hematologic condition recrudescence following SARS-CoV-2 vaccination. Blood Adv. 2021;5(13):2794-8     Previously administered products included for an unreported indication: SHINGRIX (Flare 2 years earlier which was triggered by her second Shingrix vaccine. She had never been treated with terminal complement inhibition.). Concurrent medical conditions included Paroxysmal nocturnal haemoglobinuria (long-standing history of steroid-responsive granulocyte clone size, 98%).   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 PAROXYSMAL NOCTURNAL HAEMOGLOBINURIA (admitted for further management of a PNH flare) (seriousness criteria hospitalization and medically significant), ACUTE KIDNEY INJURY (heme pigment-associated acute kidney injury) (seriousness criteria hospitalization), HAEMOLYSIS (severe hemolysis) (seriousness criteria hospitalization), CONDITION AGGRAVATED (Condition aggravated) (seriousness criterion hospitalization), INFLUENZA LIKE ILLNESS (Approximately 8 hours after receiving dose 2 she developed Flu-like symptoms), CHROMATURIA (One day after dose 2, she developed dark urine), ASTHENIA (One day after dose 2, she developed generalized weakness), ABDOMINAL PAIN (One day after dose 2, she developed abdominal pain) and ODYNOPHAGIA (One day after dose 2, she developed odynophagia). The patient was treated with METHYLPREDNISOLONE for Adverse event, at a dose of 1 gram; ECULIZUMAB (intravenous) for Adverse event, at a dose of 600 milligram and RAVULIZUMAB for Adverse event, at an unspecified dose and frequency.  At the time of the report, PAROXYSMAL NOCTURNAL HAEMOGLOBINURIA (admitted for further management of a PNH flare), ACUTE KIDNEY INJURY (heme pigment-associated acute kidney injury), HAEMOLYSIS (severe hemolysis),  CONDITION AGGRAVATED (Condition aggravated), INFLUENZA LIKE ILLNESS (Approximately 8 hours after receiving dose 2 she developed Flu-like symptoms), CHROMATURIA (One day after dose 2, she developed dark urine), ASTHENIA (One day after dose 2, she developed generalized weakness), ABDOMINAL PAIN (One day after dose 2, she developed abdominal pain) and ODYNOPHAGIA (One day after dose 2, she developed odynophagia) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): In 2021, Antibody test: negative (Negative) Negative. In 2021, Blood bilirubin: 1.8 mg/dl (Inconclusive) 1.8. In 2021, Blood creatinine: 0.91 mg/dl (Inconclusive) 0.91 and 1.69 mg/dl (Inconclusive) heme pigmentassociated acute kidney injury (baseline: 0.79 mg/dL). In 2021, Blood lactate dehydrogenase: 1272 (Inconclusive) 1272 U/L and 3282 (High) On day 2 after admission to the emergency department. In 2021, Haematocrit: 30 percent (Inconclusive) 30. In 2021, Haemoglobin: 10.0 g/dL (Inconclusive) 10.0. In 2021, Laboratory test: demonstrated severe hemolysis (abnormal) demonstrated severe hemolysis. In 2021, SARS-CoV-2 test: negative (Negative) after admission to the emergency department.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter considered PAROXYSMAL NOCTURNAL HAEMOGLOBINURIA (admitted for further management of a PNH flare), CONDITION AGGRAVATED (Condition aggravated), INFLUENZA LIKE ILLNESS (Approximately 8 hours after receiving dose 2 she developed Flu-like symptoms), CHROMATURIA (One day after dose 2, she developed dark urine), ASTHENIA (One day after dose 2, she developed generalized weakness), ABDOMINAL PAIN (One day after dose 2, she developed abdominal pain) and ODYNOPHAGIA (One day after dose 2, she developed odynophagia) to be possibly related.    Concomitant medications were not provided.  The patient received a transfusion of 2 U red blood cells (RBCs) as a treatment and received a transfusion of 1 additional unit of RBCs after admission to the emergency unit. On day 2, the patient received a transfusion of 1 additional unit of RBCs to suppress erythropoiesis. The patient received meningococcal prophylaxis with meningococcal B and ACWY vaccines without complications and was discharged on day 6 and continued on terminal complement inhibition with ravulizumab in the outpatient setting.   This case was linked to MOD-2021-263889, MOD-2021-263970, MOD-2021-264203 (Patient Link).; 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. However, the patient's medical history of paroxysmal nocturnal haemoglobinuria (including flare ups) is a confounder.