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.