PC3063: COVID-19 Triggered Fatal Pneumocystis Jiroveci (PJP) Infection in a Pediatric Patient with Anti-melanoma Differentiation Associated Gene 5 (anti-MDA5) Juvenile Dermatomyositis (JDM)

Introduction: Anti-melanoma differentiation associated gene 5 (Anti-MDA5) juvenile dermatomyositis (JDM) is frequently associated with rapidly progressive interstitial lung disease (RP-ILD) resulting in high mortality. With the COVID-19 pandemic, a surge in JDM incidence has been observed. We present a 20 month-old male with undiagnosed anti-MD5 JDM presenting with fever, rash, jaundice, cholestasis and refusal to bear weight in the setting of a COVID-19 infection. His hospital course was complicated by a PJP infection leading to a fatal outcome.

Case Description: A previously healthy 20 month-old male presented with one month of fever, rash, jaundice and acholia. An extensive workup for transaminitis and hyperbilirubinemia done during a previous admission was inconclusive. Symptoms worsened with development of respiratory distress, refusal to ambulate, and fatigue, prompting further evaluation where he tested positive for COVID-19.

On admission, hyperpigmented, scaly ulcerated lesions were noted overlying bilateral patellas, elbows, several metacarpal and interphalangeal joints, consistent with Gottron papules. Initial studies revealed cholestatic liver dysfunction, hypocomplementemia, and positive anti-smooth muscle antibodies. A comprehensive, multispecialty workup was undertaken, including liver biopsy which demonstrated non-specific findings, ruling out malignancy and hemophagocytic lymphohistiocytosis. His worsening respiratory distress prompted escalation of respiratory support, broad-spectrum antibiotics, antifungals and systemic steroids.

The chest CT revealed bilateral lower lobe infiltrates. Despite aggressive pulmonary toilet, his respiratory status worsened requiring intubation and mechanical ventilation. CT angiogram ruled out pulmonary embolism. Empiric treatment for PJP was started; however, he continued to deteriorate developing ARDS with shock and candidemia. Intensification of care included inhaled nitric oxide, high frequency oscillatory, prone positioning, and vasoactive medications. Endotracheal aspirate testing confirmed PJP infection. Immunological evaluation confirmed JDM with strongly positive anti-MDA5 antibodies for which pulse steroids were prescribed. Extracorporeal membrane oxygenation therapy was considered, however, parents declined. Unfortunately, his clinical condition progressively deteriorated to multi-organ failure and death.

Discussion: JDM is an acquired inflammatory myopathy with low incidence in the pediatric population. As with many autoimmune conditions, its presentation can be triggered or altered by viral infections. Since the COVID-19 pandemic started, a significant surge in its incidence of autoimmune conditions has been noted. Acute SARS-CoV-2 illness most commonly causes respiratory symptoms, which in patients with anti-MDA5 JDM can result in a severe RP-ILD. Viral infections are presumed to cause immunologic dysregulation, increasing the risk of opportunistic infections, especially in patients with underlying autoimmune diseases resulting in higher morbidity and mortality.

Conclusion: MDA5 JDM is an uncommon diagnosis in pediatrics. The initial presentation can be challenging given symptoms are nonspecific. Since the start of the COVID-19 pandemic, an unexpected number of new cases of JDM have been observed. We present the case of a pediatric patient with underlying anti-MDA5 JDM disease who developed rapidly progressive respiratory failure and cholestasis with co-existing SARS-CoV2 infection.