P2.021: A Breath of Fresh Air: A Systematic Approach to Pediatric Pulmonary Hypertension

Introduction: Pediatric pulmonary hypertension comprises of a variety of etiologies across different age groups. This case reiterates a systematic approach to pulmonary hypertension in children.

Case Description: A 7-year-old male with history of non-verbal autism and ventricular septal defect was admitted after a 2-month period of difficulty ambulating and orthopnea with concerns for myocarditis following a positive Rhinovirus test. Physical exam was notable for hepatomegaly and gingival bleeding/swelling. Echocardiogram on admission revealed near-systemic right sided pressures with no VSD, the tricuspid valve regurgitation velocity was recorded at 4.95 m/s, PG 98 mmHg, pulmonary valve insufficiency jet of 3.1 m/s, PG 39 mmHg, a dilated right ventricle with inversion of the ventricular septum in systole, and right to left shunting across a PFO. CT angiogram showed possible bilateral distal non-occlusive pulmonary emboli and left upper PAPVR. His clinical status deteriorated requiring intubation and PH vasodilator therapy as well as systemic tPA for possible chronic thromboembolic PH (CTEPH). Being a rare entity in pediatrics, the CT images were reviewed with international CTEPH specialists who disagreed with the emboli diagnosis. Workup for other secondary causes of PH including autoimmune, infectious, coagulation, and nutritional deficiencies revealed no abnormalities except for undetectable Vitamin C levels necessitating IV Vitamin C. Repeat CTA showed no evidence of pulmonary emboli, and cardiac catheterization showed normal hemodynamics and no significant shunting. He continued to improve, was de-escalated off all pulmonary vasodilator therapy, continued thrombus prophylaxis, and received a G-tube for continued Vitamin C supplementation and nutritional support.

Discussion: Chronic vitamin C deficiency in children can present as a constellation of exam findings such as gingival hyperplasia/bleeding, petechiae, and gait disturbances. It can occasionally cause pulmonary hypertension, as reported in a few case reports. Ascorbic acid plays an essential role in smooth muscle-mediated vasodilation as it enhances the production of endothelial cell nitric oxide, as well as it improves the overall bioactivity of nitric oxide. Though known to be a historic disease, neurodevelopment disorders in pediatric patients put them at risk for malnutrition leading to scurvy. After replacement of vitamin C in this patient, his pulmonary hypertension resolved, as well as his physical exam findings improved.

Conclusion: This case emphasizes the importance of having a broad differential for pulmonary hypertension with a systematic approach to thinking beyond congenital heart disease, autoimmune, and idiopathic pulmonary hypertension in children. With the rise in autism spectrum diagnosis across the country, physicians should attentively consider nutritional deficiencies as underlying causes for atypical diagnoses.