Prevalence of Pneumocystis jirovecii pneumonia (2010-2013): the first Croatian report.

Pneumocystis jirovecii is an important cause of interstitial pneumonia particularly among immunocompromised hosts. We analysed the prevalence of P. jirovecii pneumonia (PCP) among HIV-infected and HIV-uninfected patients presented with interstitial pneumonia or acute respiratory syndrome hospitalized in six Croatian tertiary care hospitals. Over four-year period (2010-2013), a total of 328 lower respiratory tract samples: 253 (77.1%) bronchoalveolar lavage fluid, 43 (13.1%) tracheal aspirates and 32 (9.8%) bronchial aspirates from 290 patients were examined by real-time polymerase chain reaction (PCR). PCP was detected in 23 (7.9%) patients. The prevalence of PCP differed significantly among tested groups (χ2 = 95.03; d.f. = 3; p < 0.001). HIV-infected patients were more often positive (56.6%, 95%CI = 37.3-72.4) compared to other groups (patients with malignant disease 7.7%, 95%CI = 2.6-20.3; transplant patients 7.7%, 95%CI = 2.2-24.1; patients with other diagnosis 1.5%, 95%CI = 0.5-4.4). Majority of HIV-positive patients (80%) were newly diagnosed cases. Our results indicate that HIV-infected patients still represents the main risk group for P. jirovecii infection. PCP is responsible for pneumonia in 56.6% HIV-positive patients in Croatia, primarily those who do not know that they are HIV infected.