Background Acute-onset diffuse interstitial lung diseases (AoDILD) are highly mortal condition and their cause are often difficult to discriminate. Trimethoprim 80mg/sulfamethoxazole 400mg single strength (TMP-SMX SS) has been used for Pneumocystis Pneumonia (PCP) prophylaxis and highly effective but the dose was originally developed in pediatric cancer patient's study and there is possibility that in connective tissue disease (CTD) patients, less dose can be as effective.
Objectives The aim of this study is to examine hypothesis that taking TMP-SMX for PCP prophylaxis with CTD also have prophylactic effect against AoDILD and how about those effect in under dose patients for some reason
Methods We retrospectively investigated data from 621 patients with TMP-SMX for PCP prophylaxis during and 43 patients who admitted for either acute respiratory failure/acute interstitial pneumonia/PCP/drug induced pneumonitis during 2004–2016 in our department.
Results There was no single case who admitted to hospital due to AoDILD with TMP-SMX for PCP prophylaxis. There were 34 cases admitted for AoDILD and 9 cases (26%) were dead. Among 25 cases, 5 cases developed AoDILD after TMP-SMX cessation. 70 cases ware taking under dose prophylaxis for some reasons but there was also no AoDILD case.
Conclusions Taking TMP-SMX for PCP prophylaxis may also have prophylactic effect against AoDILD. And those effect may also exist even under dose.
Hughes WT, et al.: N Engl J Med 1977;297:1419–26.
Disclosure of Interest None declared