en Pulmonology Pulmonology Original Article Original Article <span style="font-size:14px;"><span style="font-family:times new roman;"><span style="color:#0000FF;"><strong><em>Background</em></strong><em>:</em></span> Lymphangioleiomyomatosis (LAM) is a progressive lungs disease that affects women at reproductive years. Sirolimus inhibits mammalian target of rapamycin (mTOR) and its administration in past studies was hopeful in treatment of patients with LAM. The aim of this study was to evaluate sirolimus therapy on lung function in LAM patients.<br> <span style="color:#0000FF;"><strong><em>Methods</em></strong><em>:</em></span> We conducted a trial to evaluate the effect of sirolimus on six patients with LAM who had severe or very severe obstructive lung disease, and one-year follow up. Maintenance level of Sirolimus was 10-15 ng/ml. Serial visits (including physical examination, evaluation of signs and symptoms of disease and adverse events due to treatment), spirometry, 6MWT done at baseline 3, 6, 9 and 12 months after. Spirometric parameters walk distance and O₂ saturationbefore and after exercise at first and the end of treatment were measured.<br> <span style="color:#0000FF;"><strong><em>Results</em></strong><em>:</em></span> Four patients had TSC-LAM while the other 2 patients had S-LAM. The mean level of sirolimus was 13 ng/ml after one-year treatment. Mean FEV1 at enrollment and end of study was 1000cc (33% predict) and 1228cc (42% predict) respectively (P=0.674). The mean FVC at baseline and end of study was 1648cc (49% predict) and 1866cc (55% predict) (P=0.996). The mean FEV1/FVC at enrollment and the end of treatment was 58% and 62% respectively (P=0.753). The mean FEF25-75 at first and at the end of treatment was 16% and 26%, respectively (P=0.028). The mean walk distance in 6MWT at first and at the end of study was 315 meters (P=0.9). The mean percentage of O₂ saturation at rest was 84% and 92% at first and at the end of study (P=0.104).<br> <span style="color:#0000FF;"><strong><em>Conclusion</em></strong><em>:</em></span> In LAM patients, sirolimus has been shown stabilizeto or improve lung function, rest and exertional O₂ saturation. Sirolimus was effective in LAM patients who had severe or very severe physiological disorders.</span></span> Sirolimus, Lymphangioleiomyomatosis, lung function 7 10 http://caspjim.com/browse.php?a_code=A-10-1041-1&slc_lang=en&sid=1 Fatemeh Aghaeimeybodi dr.meybodi@gmail.com 100319475328460015106 100319475328460015106 No Department of Internal Medicine, Shaheed Sadoughi University of Medical Sciences, Yazd, Iran katayoun Najafizadeh Katynajafi@nritld.ac.ir 100319475328460015107 100319475328460015107 No National research institute of Tuberculosis and Lung Disease, Masih Daneshvari Hospital, Tehran, Iran seid kazem razavi ratki razavi822@gmail.com 100319475328460015108 100319475328460015108 No Department of radiology, Shahid Sadoughi University of medical sciences, Yazd, Iran nasim namiranian namiranian.nasim@gmail.com 100319475328460015109 100319475328460015109 Yes Yazd Diabetes Research Center, Shaheed Sadoughi University of Medical Sciences, Yazd, Iran