Winning Abstracts from the 2011 Medical Student Abstract Competition: A Matter of Life and Breath: A Rare Case of Pulmonary Hypertension
Author: Allison K. Nitsch, Texas A&M Health Science Center - College of Medicine, Class of 2011
Introduction: Pulmonary hypertension (PH) is a progressive disease with multiple etiologies. Management of PH is tailored to the origin of the disease, with therapy for some forms actually worsening the clinical manifestations of other subtypes. Pulmonary capillary hemangiomatosis (PCH) is a rare, but rapidly fatal cause of PH. Our case highlights how PH due to PCH is often misdiagnosed until autopsy.
Case Presentation: A 40-year-old African American female presented to the emergency department with complaints of worsening chronic dyspnea over the previous week. Her past medical history was significant for dermatomyositis and PH diagnosed with echocardiogram, which demonstrated right ventricular systolic pressures of 40 mmHg. Her PH had previously been attributed to her connective tissue disease. Her condition had continued to progress despite therapy with bosentan and sildenafil. Previous right heart catheterization revealed pulmonary artery systolic pressure of 81 mmHg, diastolic pressure 33 mmHg, and capillary mean pressure of 10 mmHg. On admission, CT scan of the chest demonstrated bilateral ground glass opacities with diffuse interlobular septal thickening and mediastinal adenopathy. The patient's condition rapidly deteriorated with increasing dyspnea and hypoxia. The patient required transfer to the ICU where she succumbed to her illness within 24 hours of admission. Autopsy ruled the primary cause of death to be progressive PH secondary to PCH. Microscopic analysis of lung tissue revealed pulmonary vaso-occlusive disease.
Discussion: Pulmonary capillary hemangiomatosis (PCH) is a rare cause of PH with fewer than 50 cases reported in the literature. PCH is marked by capillary proliferation within the alveolar walls and respiratory epithelium leading to PH. Other pathological findings include interstitial lymphocytic infiltrate, capillary proliferation and interlobular septal thickening. Etiology of PCH is unknown. PCH is similar to pulmonary vaso-occlusive disease (PVOD) clinically and pathologically. Consequently, some have suggested that PVOD and PCH are two diseases in the same spectrum or that PCH develops secondary to the congestion caused by PVOD. Clinically, PVOD and PCH are indistinguishable from primary pulmonary arterial hypertension. However, delineating PCH from other causes of PH is important as treatment of PCH with IV vasodilators in some case reports have worsened patients' clinical condition and led to pulmonary edema. Definitive diagnosis of PCH is made through lung biopsy. Successful outcomes have been reported with doxycycline, imatinib mesylate and interferon-a2 treatments in the literature. However, no treatment has been shown to improve morbidity and mortality except for lung transplantation. The imaging and right heart catheterization findings associated with PCH can facilitate rapid lung biopsy, lung transplantation and perhaps cure of these patients.