Final answer:
The appropriate treatment for Pneumocystis pneumonia (PCP) caused by Pneumocystis jirovecii in an immunocompromised patient is the combination drug trimethoprim-sulfamethoxazole (TMP/SMZ), commonly known as Bactrim.
Step-by-step explanation:
The student is inquiring about the appropriate treatment for a febrile patient on high-dose immunosuppressants with a chest X-ray (CXR) showing diffuse bilateral (B/L) ground glass infiltrates, indicative of Pneumocystis pneumonia (PCP), which is caused by Pneumocystis jirovecii. This condition is particularly concerning in immunocompromised individuals, such as those with AIDS or those undergoing immunosuppressive treatments. The recommended treatment for PCP is the combination drug trimethoprim-sulfamethoxazole (TMP/SMZ), commonly known as Bactrim. While this sulfa drug can have adverse effects, it is often lifesaving, and the risks are generally outweighed by the benefits. In severe cases or in patients with intolerance to sulfa drugs, alternative treatments such as pentamidine, atovaquone, or clindamycin in combination with primaquine may be used.