In search of markers of treatment failure and poor prognosis in IPAH - the value of mosaic lung attenuation pattern on thin-section CT scans

Table 2 Differential diagnosis of idiopathic PAH and idiopathic PVOD

	IPAH	PVOD
Genetic mutations	BMPR2 mutations 10-40%	Cases of BMPR2 mutation
Epidemiology
Sex	F:M = 2	F:M = 1
Tobacco exposure	Unrelated	More frequent than in IPAH
Chemotherapy	Case reports	Case reports
Clinical examination
Auscultatory crackles	No	Possible
Clubbing	Possible	Possible
Hemoptysis	Possible	Possible
Pulmonary function tests	Normal (possible mild restrictive)	Normal (possible mild restrictive)
DL _CO and DL _CO /VA	Often reduced	Reduced, lower than IPAH
PaO ₂ at rest	Often reduced	Reduced, lower than IPAH
HRCT	Mild abnormalities	Frequent abnormalities: Centrilobular ground-glass opacities Septal lines Lymph node enlargement
BAL	Normal	Possible occult alveolar hemorrhage
Acute NO testing	Positive: predictive of CCB response and better prognosis	Not a predictor of CCB response (risk of pulmonary edema after initiation of CCB)
Response to PAH therapy	Improved hemodynamics, functional status and outcome	PVOD may deteriorate with a risk of pulmonary edema

Definition of abbreviations: BAL, bronchoalveolar lavage; CCB, calcium channel blockers; DLCO, diffusing lung capacity for carbon monoxide; HRCT, high resolution computerized tomography; IPAH, idiopathic pulmonary arterial hypertension; NO, nitric oxide; PaO2, partial pressure of arterial oxygen; PAH, pulmonary arterial hypertension; PVOD, pulmonary veno-occlusive disease; VA, alveolar ventilation.
From [38] mod.

ISSN: 2049-6958