P2.M254: Small Vessels, Big Impact: A Patient with Granulomatosis with Polyangiitis

Introduction: Granulomatosis with polyangiitis (GPA) is an ANCA-associated small vessel vasculitis characterized by granulomatous inflammation of the upper and lower respiratory tracts, necrotizing glomerulonephritis, and involvement of other organs. Due to the rarity of this condition in children, diagnosis can be challenging and may be delayed.

Case Description: A 12-year-old male with previously well-controlled asthma, severe obesity, and type 2 diabetes mellitus presented with fevers, respiratory distress, worsening cough, chest pain, abdominal pain, peripheral edema, acute kidney injury, and dark urine. In the three months prior to his prolonged hospitalization, he had multiple pediatric intensive care unit (PICU) admissions for status asthmaticus in the setting of viral illness and recurrent emergency department visits for fever, sore throat, and ear pain with subsequent hearing loss treated as sinusitis, acute otitis media, and parotitis. He received multiple courses of steroids and antibiotics leading to transient improvement of symptoms. During this admission, he was initially managed with albuterol and steroids for status asthmaticus, alongside fluid restriction and furosemide due to suspected nephrotic syndrome. On hospital day 3, he was transferred to the PICU for worsening pulmonary edema and acute hypoxic respiratory failure requiring BiPAP. Chest and abdomen computerized tomography (CT) demonstrated bilateral pulmonary nodules and ground glass opacities (Figure 1). Renal ultrasound showed echogenic kidneys. His work up for immune mediated renal parenchymal disorders was unremarkable except for positive Proteinase 3 (PR3) antibody. Urinalysis showed nephrotic range proteinuria and hematuria. On hospital day 12, hemodialysis catheter was placed due to worsening renal function (creatinine > 7 mg/dl, urea > 170 mg/dl). He developed hemoptysis requiring massive transfusion protocol, intubation, and extracorporeal membrane oxygenation (ECMO). He was extubated on hospital day 30. He received multiple courses of IV methylprednisolone, plasmapheresis, rituximab, and cyclophosphamide for severe PR3-ANCA positive GPA manifesting with alveolar hemorrhage and rapidly progressive glomerulonephritis, with subsequent improvement in clinical course.

Discussion: This patient’s case posed a challenge due to multiple comorbidities and nonspecific symptoms which were misdiagnosed as asthma exacerbations during several visits but indicative of progressive disease. Repeated steroid courses for asthma may have contributed to delays in diagnosis by partially treating symptoms. A higher index of suspicion is warranted in pediatric patients due to the documented poorer outcomes, including greater disease severity, a higher percentage of renal impairment at disease onset, increased relapse rates, and a higher likelihood of requiring prolonged corticosteroid and immunosuppressant therapy compared to adults.

Conclusion: This case highlights the challenge and importance of timely diagnosis of GPA to decrease morbidity and mortality in children. Severe refractory asthma exacerbations, numerous ENT symptoms, renal disease, and detection of specific antibodies served as key indicators for diagnosing GPA. Timely initiation of treatment with immunosuppressive medications and utilization of ECMO proved to be lifesaving interventions.