Clinical and epidemiological features of community-acquired pneumonia during an epidemic of respiratory viral infection

Abstract

Community-acquired pneumonia (CAP) is one of the most common lower respiratory tract diseases. An increase in the CAP incidence has been reported to be associated with epidemics of acute respiratory viral infections (ARVI).Aim. Аssess clinical and epidemiological features of CAP in patients admitted to hospital during an ARVI epidemic.Methods. A cross-sectional study included 208 patient records. Medical history, physical examination, laboratory and imaging data were analyzed. CAP severity was assessed by CRB-65 scale and the systemic inflammatory response syndrome (SIRS) criteria.Results. Most CAP patients (75%) were of active working age; all presented signs of ARVI upon admission. Nasal mucosa diagnostic smears have revealed type A influenza viruses: H1N1 – 5 (83.3%) and H3N2 – 1 (16.7%) cases. 195 (93.8%) patients were not vaccinated against influenza. X-rays showed that unilateral (81.7%) and lobular pneumonia (55.8%) were the most common CAP types. 93.2% patients had nonsevere CAP, according to CRB-65. But 88 (42.3%) subjects qualified for SIRS upon admission. Concomitant conditions as risk factors of an adverse course of CAP were present in 89 patients (42.8%). Sputum analysis, if available, most frequently identified Streptococcus pneumoniae (23 cases or 38.9%) as a causative agent. Antibacterial drugs (ABD) used to treat CAP were ceftriaxone 206 (99%), macrolides 188 (90.4%), and fluoroquinolones 94 (45.2%). The initial antibacterial treatment regimens were: 186 (89.4%) prescriptions of ceftriaxone + macrolides, 16 (7.7%) prescriptions of ceftriaxone alone, and 6 (2.9%) prescriptions of levofloxacin. A switch between ABDs was reported in 78 (37.5%) cases, including 61 switches to fluoroquinolones. The median ABD administration duration was 10 (8 – 13) days.Conclusion. Most of the hospitalized CAP patients were of working age and not vaccinated against influenza. Streptococcus pneumoniae was the most common causative agent. PCR (polymerase chain reaction) smear analysis was performed only in 6 patients with ARVI, which does not allow us to assess the role of viruses and viral-bacterial associations in the etiology of CAP. In spite of non-severe CAP, all hospitalizations were justified, due to multiple risk factors of unfavorable prognosis of CAP and epidemiological factors. Most patients received a combination of generation 3 cephalosporins and macrolides as the initial therapy for CAP.