TY - JOUR T1 - Methotrexate and Trimethoprim-Sulfamethoxazole for <em>Pneumocystis pneumonia</em> Prophylaxis JF - The Journal of Rheumatology JO - J Rheumatol SP - 777 LP - 777 DO - 10.3899/jrheum.100858 VL - 38 IS - 4 AU - HAYATO YAMAZAKI AU - TOSHIHIRO NANKI AU - NOBUYUKI MIYASAKA AU - MASAYOSHI HARIGAI Y1 - 2011/04/01 UR - http://www.jrheum.org/content/38/4/777.abstract N2 - To the Editor:We read with interest the recent article by Katchamart, et al1 about Canadian recommendations for the use of methotrexate (MTX) in patients with rheumatoid arthritis (RA). The authors conclude that trimethoprim-sulfamethoxazole (TMP-SMX) should be avoided in RA patients treated with MTX. This recommendation was based on several case reports and a retrospective case-control study in which concomitant use of TMP-SMX and MTX was associated with blood dyscrasias1. In their cases, therapeutic doses of TMP-SMX were prescribed to treat urinary tract infection or other infectious diseases, but chemoprophylactic doses of TMP-SMX for Pneumocystis pneumonia (PCP) were not included. We believe that these 2 clinical indications for treatment with TMP-SMX should be considered separately. In fact, the contraindication for TMP-SMX use for … Address correspondence to Prof. M. Harigai, Department of Pharmacovigilance, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, Japan. E-mail: mharigai.mpha{at}tmd.ac.jp ER -