Acute Respiratory Distress Syndrome Requiring Extracorporeal Membrane Oxygenation as the Initial Presentation of Anti-neutrophillic Cytoplasmic Auto-antibody Positive Vasculitis.

Acute respiratory distress syndrome (ARDS) is a life-threatening inflammatory state of lung injury that can require acute interventions including mechanical ventilation as well as emergent veno-venous extracorporeal membrane oxygenation (VV-ECMO) for management. Etiologies of ARDS are not clearly discernible in certain cases and can vary from sepsis, pneumonia, trauma and intoxication. Anti-nuclear cytoplasmic auto-antibody (ANCA)-associated vasculitis (AAV) is a group of several conditions that can have pulmonary complications including ARDS. We present a case where the primary manifestation of myeloperoxidase (MPO)-ANCA positive vasculitis was ARDS, in order to highlight the importance of investigating rare vasculitides as the underlying cause of ARDS and the importance of ECMO as an early life-saving intervention for the management of ARDS.

Pulmonary fibrosis and microscopic polyangiitis in a 75-year-old woman.

We present a case of a 75-year-old woman who admitted in the internal medicine department for a recent onset of persisting moderate daily fever and fatigue that started 30 days prior to her hospitalization. Her past medical history is remarkable for mild pulmonary fibrosis, megaloblastic anaemia, and hypergammaglobulinaemia of no obvious causes. On presentation, she was febrile (38°C) and had high ESR and CRP levels, but most of her laboratory tests were within normal levels and had no signs of arthritis or rash. She was hospitalized for suspected lower urinary tract infection and started on antibiotics. During hospitalization, her renal function deteriorated together with microscopic haematuria, proteinuria and granular urine casts in urine analysis and her inflammation markers raised further. A renal biopsy revealed glomerulonephritis with pauci-immune crescents, and serology tests were positive for anti-MPO p-ANCA, both suggesting a diagnosis of microscopic polyangiitis (MPA). While high-dose methylprednisolone pulses and cyclophosphamide were introduced intravenously, there was no remission, but respiratory failure occurred that led to patient's intubation and transfer to the ICU. She died a few days later due to septic shock. Asymptomatic pulmonary fibrosis can precede microscopic polyangiitis for several years and is associated with a poor prognosis.