Current Trend in the Antibiogram of Bacterial Pathogens of Adult Lower Respiratory Tract Infections in a Nigerian Tertiary Hospital

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 Klebsilla pneumoniae 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.