Case description:
Seventeen-year-old male with a past medical history (PMH) of obesity and persistent asthma was hospitalized due to COVID-19 pneumonia with hypoxemia, requiring respiratory support via High Flow Nasal Cannula (HFNC). He was treated with a 5-day course of Remdesivir, Dexamethasone, Azithromycin, and was placed on Beclomethasone Inhaled 80mcg (2 puffs) twice daily. Moderate bilateral infiltrates on chest x-ray improved upon discharge. One month later, the patient was readmitted with elevated blood pressure, hematuria, proteinuria and diagnosed with acute kidney injury (AKI). AKI was thought to be due to dehydration, with improvement observed after a few days of fluid management and subsequent normalization of blood pressure. He was subsequently discharged.
One month following the second hospital admission, he presented to ER with worsening cough and amber colored urine. He reported fatigue, dry cough, and dyspnea with exertion since initial hospitalization. He also revealed that he had long standing knee, lower back pain, and overall body aches, which were intensified after initial COVID infection. He developed respiratory insufficiency requiring HFNC and was revealed to have anemia (hemoglobin of 5.9). Computed Tomography Angiography (CTA) showed no evidence of pulmonary embolus but did show extensive heterogeneous infiltrates in both lungs with an unusual fluffy central distribution concerning for diffuse alveolar hemorrhage (DAH) (Figure 1). Flexible Fiberoptic Bronchoscopy with Broncho-Alveolar Lavage (FFB/BAL) demonstrated DAH as evidenced by the BAL return color and RBC presence, along with positive hemosiderin-laden macrophages. Respiratory culture and PCR respiratory panel from BAL were negative for an infectious etiology. Rheumatologic evaluation revealed ANA, P-ANCA, and MPO antibody positivity, leading to a diagnosis of ANCA positive vasculitis. Renal biopsy revealed necrotizing glomerulonephritis with limited immune complex deposition.
The patient was initially treated with 3 days of pulse methylprednisolone (1 gram per day, divided every 6 hours) and underwent 5 days of plasmapheresis. Steroids were subsequently decreased to 30 mg every 8 hours (~0.85mg/kg/day) of Methylprednisolone, and prior to discharge were transitioned to oral prednisone. Following plasmapheresis, he was started on Cyclophosphamide infusions 10 mg/kg IV every 2 weeks. His respiratory status improved, acute renal failure resolved, and he was discharged on room air without need for outpatient dialysis.