抄録
Severe pulmonary arterial hypertension (PAH) is a fatal disease, although lung transplantation is an option when medical therapy is exhausted. In Japan, the most common approach is living-donor lobar lung transplantation (LDLT). Outcomes after LDLT are steadily improving but remain poorer than those for heart transplantation, mainly because of the high incidence of post transplant bronchiolitis obliterans syndrome (BOS), which sometimes occurs later than 10 years after surgery. BOS is rare in LDLT, and the symptoms are milder than those associated with cadaveric lung transplantation as a result of hemilateral lung rejection of donor tissue. Furthermore, onset is usually insidious.
Here, we report a case of a 27-year-old woman with BOS that developed 15 years after LDLT for severe heart failure (New York Heart Association functional class IV) caused by idiopathic PAH. The ABO blood type-compatible donors were the parents of the patient, who received subsequent treatment with cyclosporin A, mycophenolate mofetil, and low-dose prednisolone. She had been well and working full-time, but her trough cyclosporin A level had decreased to ＜150 mg/dL because of poor drug compliance 1 year before admission. Fifteen years after transplantation, the patient reported mild dyspnea while walking up stairways. A pulmonary function test showed reductions in forced expiratory volume in one second (FEV1) (＜70%) and maximum midexpiratory flow (＜25%). Lung perfusion scintigraphy revealed BOS of the right lung (her father's right lower lung). Aggressive treatment included intravenous methylprednisolone, oral azithromycin, inhalation of bronchodilators, tiotropium bromide, and beclomethasone as well as dose adjustment of cyclosporin A and mycophenolate mofetil. Because of these treatment modifications, her status remained unchanged (Hugh-Jones I) and did not worsen. In conclusion, even 15 years after LDLT, BOS manifesting as chronic allograft rejection may occur if anti–graft rejection medication is not properly administered.
