A case of interferon-α-induced pulmonary arterial hypertension after living donor liver transplantation.

Pulmonary arterial hypertension (PAH) is a progressive and life-threatening disease characterized by elevated pulmonary vascular resistance, which results in right-heart failure. We present a case of interferon (IFN)-α-induced PAH developed after living donor liver transplantation. Although IFN is categorized as a "possible" risk factor for PAH in the current international classification, it is still under recognized. Moreover, the prognosis of IFN-induced PAH is poor in the limited number of published cases. In our case, we achieved good outcome by the withdrawal of IFN and administration of combination therapy using tadalafil, beraprost, and treprostinil. Since IFN is an important treatment option in current medical therapy, its contribution to the pathogenesis of PAH should be taken into consideration. In conclusion, our case suggests the importance of PAH screening in patients treated with IFN.