Clinical study of sirolimus-associated interstitial pneumonitis in kidney transplant recipients

Objective To study the sirolimus (SRL)-associated interstitial pneumonitis,which is a severe side effect of sirolimus therapy. Methods In 7 renal grafts treated with SRL, interstitial pneumonitis (8 times) was diagnosed. One patient suffered a relapse after sirolimus treatment was given again. Two patients received de novo sirolimus treatment, and rest 5 patients were switched from a calcineurin inhibitor-containing regimen to a SRL-based protocol for various indications: chronic allograft nephropathy (n = 4) and cancer (n = 1 ). The patients presented with fever, dyspnea on exertion and the chest X-ray or computed topographic (CT) scan on admission showed bilateral mostly peripheral interstitial infiltrates. Results SRL was discontinued in 4 patients and the dose was reduced in the remaining 3 patients. Symptoms were improved within 3-14 days in all patients, the radiographic findings improved within 2-4 weeks, and the lesions were absorbed completely in 2-6 months.Conclusion The frequency of interstitial pneumonitis appears to be increased in renal transplant patients receiving SRL. Discontinuation or reduced dose of SRL appears to be the safest treatment option for the patients with interstitial pneumonitis. Key words: Kidney transplantation;  Sirolimus;  Lung diseases, interstitial