Assessment of Biofilm Formation in Extended Spectrum Beta-Lactamase-Producing <i>Klebsiella pneumoniae</i>

therapy and promoting antibiotic resistance [1, 2].Klebsiella pneumoniae, a commensal bacterium of the human gastrointestinal tract, skin, and nasopharynx, is a major pathogen that causes both community-acquired and nosocomial infections, including urinary and biliary tract infections, septicemia, and pneumonia [3].Biofilm formation in K. pneumoniae [4] involves the aggregation of microbial cells enclosed in a self-produced polysaccharide matrix that adheres to biological surfaces [5].Drug-resistant K. pneumoniae, particularly extended-spectrum -lactamase (ESBL)-pro- ducing strains, causes a substantial antibiotic management problem in treating patients with infections, thereby increasing mortality rates.ESBL-producing K. pneumoniae isolates have greater potential to form biofilms than non-ESBL producers [1, 4, 6].Most K. pneumoniae isolates expressed two types of fimbrial adhesins (types 1 and 3).