Summary

The authors discuss the case of a 7-year-old female who presented with exertional cyanosis and was found to have pulmonary arterial hypertension. Despite normal left-sided heart function, the patient developed pulmonary oedema in response to pulmonary vasodilator therapy, increasing suspicion for pathology in the pulmonary capillaries and veins. Lung biopsy confirmed a diagnosis of pulmonary capillary haemangiomatosis (PCH), a rare cause of pulmonary hypertension in both children and adults. The diagnosis requires lung biopsy and is often made postmortem. She was treated with interferon α-2a and doxycycline for their antiangiogenic properties and reports of disease regression. Although she initially demonstrated improvement in her pulmonary hypertension in response to these medications, she succumbed to the disease within the time frame previously reported for PCH.