Features of severe community acquired pneumonia in hiv-infected patients

Questions of management of patients with severe community acquired pneumonia (CAP) in HIV-infected are particularly acute. Pneumonia etiology, identification and treatment on the background of immune deficiency, its clinical and diagnostic features and tactics are still not clearly described, this significantly increases mortality from CAP in general clinical practice. That is why the aim of the work was to determine clinical features, etiology, severity of systemic inflammation and cellular immunity status of severe pneumonia in HIV-infected individuals. For this, 62 patients with verified severe CAP were observed, after express testing the main group included 11 (17.7%) persons with severe CAP and identified HIV-infection who underwent identification of respiratory pathogens, determination of serum levels of markers of systemic inflammation (procalcitonin (PCT) and C-reactive protein (CRP)), count of CD4, CD8, CD4/CD8 lymphocyte subpopulations. According to the results of causative agent identification in the study group pneumonia caused by Pneumocystis jirivecii (in 9 (81.8%) of cases) dominated, whereas in 2 other patients (18.2%) Streptococcus pneumonia was identified. According to the results of objective examination it turned out that the peculiarities of severe CAP in HIV infected patients is non-manifestal atypical clinical set of symptoms with predominance of respiratory distress syndrome over general intoxication, due to Pneumocystis pathogenetic mechanisms of lung injury (BR in the study group was at 37,5±0,1 per 1 min. of oxygen saturation 79,2±3,0%), and with following minimal inflammatory processes (maximum level of PCT in patients with pneumocystis pneumonia corresponded 0.555 ng/ml). According to the study of cellular immunitit it was found that of study group patients had CD4 count 65% less than in the control group. It turned out that in cases of suspected severe CAP in HIV-infectsd patients sputum PCR method allows to quickly detect atypical respiratory pathogens (including Pneumocystis). Determination of serum levels of biomarkers allows to be oriented towards the cause of severity state of patients with severe CAP, and the need in antibiotic therapy. Determination of CD4, CD8, CD4/CD8 markers has high differential diagnostic value in patients with severe CAP and HIV infection, especially in the absence of evidence of immunodeficiency.