The aim of this study was to compare the clinical characteristics of pneumocystis pneumonia (PCP) between patients with rheumatoid arthritis (RA) being treated with biologics and those being treated without biologics.
From 8,630 patients with RA in our institution, we enrolled 24 patients who had developed PCP during the course of their treatment. They were divided into two groups according to the treatment they were receiving for RA: the biologics group (
At PCP diagnosis, the biologics group showed significantly lower serum levels of 
The finding that RA patients being treated with biologics developed PCP with relatively normal lymphocyte counts and lower 