Major Bacteria of Community-Acquired Respiratory Tract Infections in Turkey

SUMMARY: To determine the bacterial etiology of lower respiratory tract infections (LRTIs) in Turkey, quantitative cultures of sputum were carried out. The major pathogens for LTRIs were found to be Haemophilus influenzae, followed by Streptococcus pneumoniae and Moraxella catarrhalis. Only 6.1% of the H. inlfuenzae and all strains of M. catarrhalis were β-lactamase producers. An E-test showed that 31.2% of the S. pneumoniae strains had an intermediate resistance to penicillin, and the remaining strains were susceptible; no fully resistant strains were detected. From the perspective of the world community, acquired lower respiratory tract infections (LRTIs) are an important cause of morbidity and mortality for all age groups. Each year, approximately 7 million people die as a direct consequence of acute and chronic respiratory infection (1). LRTIs are very common, with an incidence in the world population of 40 - 50 per 1,000 (2,3). Since the etiological agents of LRTIs cannot be determined clinically, microbiological investigation is critical for both treatment and epidemiological purposes. A quantitative sputum culture is a reliable and noninvasive procedure used for the determination of causative bacteria (4,5). Although a sputum culture has the advantage of high sensitivity, routine laboratories are not able to perform this test for various reasons. Therefore, antimicrobial therapy for LRTIs is frequently empirical, generally presumptive and instituted before the etiology of the specific disease is known. Empirical antimicrobial choice is complicated by the increasing prevalence of resistance of some of the common LRTI pathogens to antibiotics (6). In order to select appropriate antibiotics for empirical therapy, epidemiological studies are critical to identify the actual causative microorganism and to determine whether it is susceptible to antibiotics. To save lives and to reduce mortality with proper treatment, there is no alternative other than to obtain this information for each country. Information in this regard is scarce in Turkey. The present study represents a joint effort between respirologists, infectious disease specialists, and microbiologists to introduce a platform for continued future surveillance. To determine the bacterial etiology of LRTIs, their resistance to antibiotics and β-lactamase production was determined in two major hospitals in Ankara, Turkey, in a prospective study. Between September of 2002 and April of 2003, sputum samples were collected from adult LRTI patients who were attending the inpatient and outpatient clinics of the Ataturk Chest Disease and Chest Surgery Central Education and Research Hospital, and Ibni Sina Hospital, Ankara.