<prompt> About Pneumocystis pneumonia the true statement is:The causative organism is a protozoanDrug of choice is Trimethoprim-Sulfamethoxazole CotrimoxazoleMost common radiological appearance is a bat wing distribution of infiltrates with pneumocysts in peripheral fieldsSteroids have no role in the therapy of Pneumocystis pneumonia  <response>: Pneumocystis jirovecii is a fungus responding to Cotrimoxazole. It causes opportunistic pneumonia in patients with HIV infection. The most common radiology finding is a normal X-ray chest. However, the most typical X-ray is a bat wing distribution of infiltrates with pneumocysts in peripheral fields. Steroids are combined with Cotrimoxazole in treatment of severe Pneumocystis jirovecii pneumonia. 