<prompt> Which of the following does not cause pulmonary hypertension?Sickle cell anemiaFenfluramineHyperventilationScleroderma  <response>: ANSWER: C HyperventilationREF: Harrison 17th ed chapter 244Fenfluramine is known to cause PAHPulmonary arterial hypertension PAHIdiopathic IPAH formerly PPHFamilial FPAHAssociated with APAH:C ollagen vascular diseas eCongenital systemic-to- pulmonary shuntsPortal hypertensionHIV infectionDrugs and toxinsOther thyroid disorders, glycogen storage disease, Gaucher disease, hereditary hemorrhagic telangiectasia, hemoglobinopathies, myeloproliferative disorders, splenectomyAssociated with significant venous or capillary involvementPulmonary veno-occlusive disease PVODPulmonary capillary hemangiomatosis PCHPersistent pulmonary hypertension of the newbornPulmonary hypertension with left heart diseaseLeft-sided atrial or ventricular heart diseaseLeft-sided valvular heart diseasePulmonary hypertension associated with lung diseases andor hypoxemiaChronic obstructive pulmonary diseaseInterstitial lung diseaseSleep-disordered breathingAlveolar hypoventilation disordersChronic exposure to high altitudeDevelopmental abnormalitiesPulmonary hypertension due to chronic thrombotic andor embolic diseaseThromboembolic obstruction of proximal pulmonary arteriesThromboembolic obstruction of distal pulmonary arteriesNonthrombotic pulmonary embolism tumor, parasites, foreign materialMiscellaneousSarcoidosis, histiocytosis X, lymphangiomatosis, compression of pulmonary vessels adenopathy, tumor, fibrosing mediastinitis 