Pneumocystis Jirovecii Pneumonia in Two Immunosuppressed Non-HIV Infected Patients: A Clinical and Therapeutic Analysis.

Pneumocystis jirovecii pneumonia (PJP) is an opportunistic fungal infection that often occurs secondary to human immunodeficiency virus (HIV) infection. However, for non-HIV immunocompromised patients, such as those undergoing novel immunosuppressive treatments to manage malignancies, organ transplants, or connective tissue diseases, PJP is emerging as an increasing threat. The clinical manifestations of PJP in HIV-infected and non-HIV-infected patients differ significantly. In non-HIV-infected patients, PJP progresses rapidly and is challenging to diagnose, resulting in severe respiratory failure and a poor prognosis. We describe lymphocytopenia in two women who were recently treated with methotrexate, tacrolimus, and corticosteroids for immunosuppressive therapy following adjuvant chemotherapy for breast cancer and kidney transplantation. The initial examination included a high-resolution chest CT indicating atypical pneumonia, and treatment was initiated with trimethoprim - sulfamethoxazole and oxygen support. Subsequently, bronchoscopy and bronchoalveolar lavage with mNGS detected Pneumocystis jirovecii. After 3 weeks of treatment with cotrimoxazole, the two patients recovered significantly and their condition was stable.