Acute focal segmental necrotizing crescentic GN, Granulomatosis with Polyangiitis; This literature case was received on 08-May-2023, reported by other healthcare professional and concerned a patient of a 45-year-old, male patient.   The patient's medical history and concomitant medications were not reported.   On an unspecified date, the patient was vaccinated with influenza vaccine (brand not specified; dose, route of administration, anatomical location, and indication: not reported). The batch number was not reported.  On an unspecified date, four weeks after receiving influenza vaccine, the patient presented with subacute onset pleuritic chest pain and shortness of breath. The patient was feeling weak. On presentation, the patient was hemodynamically stable. The patient's exam was notable for bibasilar crackles. The patient had positive rheumatoid factor. The patient's computerised tomogram (CT) chest was notable for multiple ground glass nodules at the right upper lobe. The patient's creatinine was 1.64 mg/dL. The patient's urine albumin to creatinine ratio was 225 mg/gm creatinine and urine protein to creatinine ratio was 500 mg/gm creatinine. The patient had 25-30 red blood count (RBC)/HPF with no dysmorphic RBCs. The patient had strongly positive antineutrophil cytoplasmic antibody (PR3-ANCA) antibody (>8 AI). The patient's kidney biopsy revealed acute focal segmental necrotizing crescentic glomerulonephritis (GN), pauci-immune type. The patient was treated with pulse intravenous (IV) methylprednisolone and rituximab at a dose of 375 mg/m2 weekly for four doses. Three months following induction therapy the patient's creatinine improved from a peak of 3.6 mg/dL to 1.4 mg/dL. The patient's CT findings and haematuria resolved. The patient's PR3- ANCA slowly decreased and became negative six months after induction. This patient's presentation with lung nodules on chest CT, necrotizing crescentic GN on kidney biopsy and high serum level of PR3-ANCA support a diagnosis of Granulomatosis with Polyangiitis with a strong temporal relationship to vaccination against influenza.  The outcome of the event was not reported.   The reporter assessed the events to be possibly related to influenza vaccine. As reported, the patient was diagnosed with Granulomatosis with Polyangiitis with a strong temporal relationship to vaccination against influenza. This was the nineth case of ANCA associated vasculitis following influenza vaccination reported in the literature. Clinicians should be aware of the possible association between systemic vasculitis and influenza vaccination.  The event of 'necrotizing granulomatous vasculitis' was considered to be medically significant by a Physician within Seqirus's Pharmacovigilance and Risk Management Department.  The literature reference is   Company comment: On an unspecified date, four weeks after receiving influenza vaccine, the patient presented with weakness, pleuritic chest pain and shortness of breath. The diagnostic findings, lung nodules on chest CT, necrotizing crescentic glomerulonephritis (GN) on kidney biopsy and high serum level of positive antineutrophil cytoplasmic antibody (PR3-ANCA) antibody support a diagnosis of granulomatosis with polyangiitis. The patient's medical history and concomitant medications were not reported. Causal role of the suspect vaccine is assessed as possibly related for granulomatosis with polyangiitis, due to plausible chronology and no alternative aetiology provided.; Reporter's Comments: As reported, the patient was diagnosed with Granulomatosis with Polyangiitis with a strong temporal relationship to vaccination against influenza.; Sender's Comments: On an unspecified date, four weeks after receiving influenza vaccine, the patient presented with weakness, pleuritic chest pain and shortness of breath. The diagnostic findings, lung nodules on chest CT, necrotizing crescentic glomerulonephritis (GN) on kidney biopsy and high serum level of positive antineutrophil cytoplasmic antibody (PR3-ANCA) antibody support a diagnosis of granulomatosis with polyangiitis. The patient's medical history and concomitant medications were not reported. Causal role of the suspect vaccine is assessed as possibly related for granulomatosis with polyangiitis, due to plausible chronology and no alternative aetiology provided.