Detection of Pneumocystis Jirovecii by PCR in Patients with Lung Cancer: A Preliminary Study

Introduction: Infection complications in lung cancer (LC), one of the most common cancers in the world, are still among the most important causes of death. Of them, P. jirovecii, which is as an opportunistic infection, causes a life-threatening type of pneumonia in cancer patients. This preliminary study aimed to determine the incidence and clinical status of P. jirovecii by PCR in lung cancer patients compared to the conventional method. Material and methods: Sixty-nine lung cancer patients and fSorty healthy individuals were included in the study. After sociodemographical and clinical features were recorded, sputum samples were collected from attenders. Firstly, microscopic examination was made with Gomori's methenamine silver stain and then PCR was performed.Results: P. jirovecii was detected in three of 69 lung cancer patients by PCR (4.3%), but not by microscopy. However, healthy individuals were negative for P. jirovecii by both methods. Based on clinical and radiologi-cal findings, P. jirovecii was evaluated as probable infection in one patient and colonization in the other two patients. Although PCR is more sensitive than conventional staining methods, it cannot distinguish probable and proven infections from pulmonary colonization.Discussion: It is important to evaluate the decision of infection together with laboratory, clinical and radiolog-ical findings. Moreover, PCR may enable to know the colonization and to take precautions such as prophy-laxis, due to the risk of colonization turning into an infection in immunocompromised patient groups. Further studies involving larger populations and evaluating the colonization-infection relationship in patients with solid tumors are needed.(c) 2023 SFMM. Published by Elsevier Masson SAS. All rights reserved.