Pneumocystis pneumonia in children – the relevance of chemoprophylaxis in different groups of immunocompromised and immunocompetent paediatric patients

INTRODUCTION: Pneumocystis jirovecii is an opportunistic pathogen causing pneumocystis pneumonia (PCP), a life-threatening infection, in immunocompromised patients. In this study, retrospective analysis of the presence of P. jirovecii DNA in different samples collected from children with suspected PCP was carried out. MATERIAL AND METHODS: Three hundred and six specimens [152 bronchoalveolar lavage (BAL) specimens, 80 blood specimens, 18 bronchial secretions (BS), 34 induced sputum samples, 10 endotracheal aspirates (ETA), and 12 other type samples] obtained from patients with suspected PCP were examined by real-time PCR. RESULTS: Forty (13.1%) patients were positive for P. jirovecii: 4 (7.7%) patients with malignancies, 3 (6.8%) transplant recipients, 15 (23.1%) other immunocompromised patients, and 18 (12.4%) immunocompetent patients. Pneumocystis jirovecii DNA was detected in 20.4% of BAL specimens, 11.1% of BS samples, 10% of ETA sample, 8.8% of induced sputum samples, and in 3.7% of blood samples. Comparing the frequency of the presence of P. jirovecii DNA between the group of children treated with PCP chemoprophylaxis (malignancy patients and transplant recipients) and a group of children not receiving this prophylaxis (other immunocompromised and immunocompetent children), we found that the occurrence of PCP was twice as high in the latter group of children (7.3% and 15.7%, respectively). CONCLUSIONS: Respiratory samples, such as BS, BAL, or ETA specimens, are the material of choice for the diagnosis of PCP. Due to high incidence of PCP in certain groups of immunocompetent and immunocompromised patients, besides cancer patients and transplant recipients, consideration of PCP prophylaxis is required in these groups as well.