Sputum bacterial identification in patients with bronchial asthma exacerbation

Abstract

Background The role of bacterial pathogens in exacerbations of bronchial asthma is unclear as that of viral infections. Aim To identify sputum bacteria and antibiotic sensitivity in patients with bronchial asthma exacerbation. Patients and methods A descriptive cross-sectional study was conducted on 50 patients with acute bronchial asthma exacerbation. Spirometeric pulmonary function tests, total and differential leukocyte count, sputum Gram stain, culture, and sensitivities were done for all patients. Results Of the studied patients, 50% have growth of normal flora, 12% have fungal growth, and 38% have bacterial growth (63.6 and 36.4% of them have Gram-negative and Gram-positive bacteria, respectively). The most predominant bacteria were Klebsiella pneumoniae (31.8%) and Streptococcal pneumoniae (18.2%), while Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii complex, and Enterobacter aerogenes are equally distributed (9.1%). There was a significant decrease of vital capacity %, forced vital capacity %, and forced expiratory volume in the 1 s % in bronchial asthma with Gram-negative bacteria compared with those with Gram-positive bacteria. The total and differential leukocytic counts nonsignificantly differed between both subgroups. Among the studied patients with bacterial growth, Amikacin, Quinupristin/Dalfopristin, Linezolid, Vancomycin, and Tigecycline were the most common sensitive antibiotics (100%), followed by Tobramycin, Ciprofloxacin, Levofloxacin, and Gentamicin (95.5%). On the other hand, Benzylpenicillin and Oxacillin were the most common resistant antibiotics (100%), followed by Ampicillin (92.3%). Conclusion Bacterial organisms were responsible for only about one-third of bronchial asthma exacerbation, with predominance of Gram-negative organisms. Amikacin, Quinupristin/Dalfopristin, Linezolid, Vancomycin, and Tigecycline, Tobramycin, Ciprofloxacin, Levofloxacin, and Gentamicin were the most common sensitive antibiotics. Benzylpenicillin, Oxacillin and Ampicillin were the most common resistant antibiotics.

Keywords

• acute asthma exacerbation
• bacterial etiology
• bronchial asthma
• etiology of asthma exacerbation
• gram-negative organisms