Abstract
Methotrexate has immunosuppressive effects and is administered for refractory
chronic urticaria. We present a case of
Pneumocystis jirovecii pneumonia in a
patient with refractory
chronic urticaria managed by low-
dose weekly
methotrexate treatment (total cumulative
dose 195mg). Our study highlights the importance of providing prompt
diagnosis and
treatment of
Pneumocystis jirovecii pneumonia in
patients with
chronic urticaria under
methotrexate therapy.