Bacterial Aetiologies of Lower Respiratory Tract Infections among Adults in Yaoundé, Cameroon

Abstract

Lower respiratory tract infections (LRTIs) remain a challenge in African healthcare settings and only few data are available on their aetiology in Cameroon. The purpose of this study was to access the bacterial cause of LRTIs in patients in Cameroon by two methods.Methods. Participants with LRTIs were enrolled in the referral centre for respiratory diseases in Yaoundé city and its surroundings. To detect bacteria, specimens were tested by conventional bacterial culture and a commercial reverse-transcriptase real-time polymerase chain reaction (RT-PCR) assay. One hundred forty-one adult patients with LRTIs were enrolled in the study. Among the participants, 46.8% were positive for at least one bacterium.Streptococcus pneumoniaeandHaemophilus influenzaewere the most detected bacteria with 14.2% (20/141) followed byKlebsiella pneumoniae, 9.2% (13/141),Staphylococcus aureus, 7.1% (10/141), andMoraxella catarrhalis, 4.3% (6/141). Bacterial coinfection accounted for 23% (14/61) withHaemophilus influenzaebeing implicated in 19.7% (12/61). The diagnostic performance of RT-PCR for bacteria detection (43.3%) was significantly different from that of culture (17.7%) (p< 0.001). OnlyStreptococcus pneumoniaedetection was associated with empyema by RT-PCR (p<0.001). These findings enhance understanding of bacterial aetiologies in order to improve respiratory infection management and treatment. It also highlights the need to implement molecular tools as part of the diagnosis of LRTIs.