Comparison between giemsa staining, toluidine blue o (TBO) staining, direct immunofluorescent monoclonal antibody (DFA) staining and real-time polymerase chain reaction (PCR) methods for diagnosing Pneumocystis jiroveci

Pneumcystis jiroveci is an opportunistic pathogen especially affecting lungs in immune-suppressed patients. According to the increased number of patients with AIDS the agent is frequently faced with in recent years. Because of the impossibility of culturing in vitro conditions it is difficult to be diagnosed. The treatment of the illness takes long time and has lots of side effects. There can be same problems in prophylactic treatment before diagnosis. Early diagnosis is important because of the high mortality. As a result, rapid and reliable methods are needed in PCP.In our study, in a risk group of 57 patients we collected 57 clinical samples and searched the agent with Giemsa, TBO, DFA and RT-PCR. P. jiroveci was indicated by Giemsa with five (8.7%), TBO with four (7%), DFA with seven (12.3%) and RT-PCR with seven (12.3%) of 57 patients. There was one specimen that was positive by DFA staining but negative by real-time PCR. On DFA staining cysts were rare and hollow in this specimen. When it was confirmed with the clinical findings, the positive results were mostly obtained by RT-PCR. The sensitivity and specificity of Giemsa, TBO and DFA compare with RT-PCR were determined respectively as %72 - %100, %57 - %100, %86 - %98.As a result the diagnosis and the treatment of PCP are very difficult and have high risk of mortality and morbidity. We think that real-time PCR is a convenient method that can be used in the rapid and correct diagnosis of this opportunistic pneumonia.