“…The differential diagnosis of PH also includes obstructive processes of the intrapulmonary vessels, such as peripheral arterial stenoses, recurrent thromboembolism, stenoses of the terminal preatrial veins, vasculitides, veno-occlusive disease, and others (2,10,14). For evaluation for these conditions, a gradual use of the following investigations is nesessary: thorough laboratory tests for infections, inflammation, coagulation, and immunologieal processes; chest radiography and CT, pulmonary perfusion scintigraphy and angiography (4,10,14). All these investigations were normal in our patient.…”