ABSTRACT
Background: Lower respiratory tract infections (LRTIs) are among the commonest infectious diseases requiring hospitalization. There is an increasing resistance development of bacterial pathogens of LRTIs to the commonly prescribed antibiotics necessitating regular surveillance for these bacteria and their antibiogram. Aim: To identify bacterial pathogens of adult LRTIs, determine their antibiotic susceptibility pattern, and suggest the best empirical treatment of adult LRTIs in the setting. Study Design: Descriptive cross-sectional study. Methods: A total of 194 respiratory samples from 194 consecutive consenting adult in-patient of a Federal Teaching Hospital were processed. Identification of isolated bacteria and antibiotic susceptibility testing of the isolates were carried out following the standard protocol. Results: Bacteria isolation was seen in 52.1% of all specimens, highest isolation rate was from sputum (55.2%). Isolation was higher in males (54.9%) than females (48.1%) but no significant |
difference was seen (P=0.36). Gram negative bacteria were predominantly isolated (64.4%) and Klebsillapneumoniae was the most common (33.7%). Eight extended-spectrum beta-lactamase (ESBL) producers and 3 methicillin-resistant Staphylococcus aureus (MRSA) were also detected. All isolates were sensitive to imipenem and meropenem. All MRSAs were sensitive to vancomycin. There was poor sensitivity pattern seen against most antibiotics tested.
Conclusion: Gram negative bacteria were the predominant bacterial pathogen isolated, and isolates were resistant to most antibiotics tested, though, all were sensitive to carbapenems. Levofloxacin plus gentamicin, and carbapenems were the suggested first and second line empirical treatment of choice respectively for adult LRTIs in this and similar settings.
CHAPTER ONE
Infections of the lower respiratory tract, a region from the trachea to the alveoli include pneumonia, emphysema, lung abscess, bronchiolitis, bronchitis, bronchiectasis, lung abscess, and pleural effusion. Acute forms of these infections are among the commonest human infectious diseases globally. Human of all age-groups are affected with associated significant morbidity and mortality [1, 2]. They are a significant contributor to out-patient consultation (6%) and all hospital admission (4.4%). Among adults up to 60 years, lower respiratory tract infections (LRTIs) account for 3%-5% of mortality [3]. Globally, it is estimated that about 4.2 million deaths from acute LRTIs occur among all age groups annually. However, the burden of the diseases is higher in developing countries, where pneumonia is among the most common cause of hospital attendance among adults [4]. The morbidity and mortality arising from these infections varies depending on the underlying etiological agents and their virulence [5]. The incidence and associated mortality due to LRTI can be influenced by several factors including characteristics of the population at risk, standard of the healthcare facilities available, use of immunosuppressive drugs, inappropriate antibiotic therapy, distribution of causative agents, and prevalence of antimicrobial resistance [6]. Each of the different types of LRTIs presents