In addition to clinical factors such as a shorter median course (2 months vs 6 months), interstitial lung disease (92.9% vs 70.4%), presence of diabetes (42.9% vs 13.6%), and higher prednisone exposure (50 mg vs 30 mg), we also found that laboratory parameters such as higher erythrocyte sedimentation rate and ferritin value, lower serum albumin, CD4+ T lymphocyte count, and overall lymphocyte count were all significantly different between PJP− and PJP+ IIM patients (P < 0.05). Here, CD4 is linked to pneumocystosis.