Extended-spectrum beta-lactamase-producing Klebsiella pneumoniae hospital acquired bacteremia. Risk factors and clinical outcome

OBJECTIVE: To study the risk factors and clinical outcome in patients having extended-spectrum beta-lactamase producing (ESBL) Klebsiella pneumoniae (K. pneumoniae) hospital acquired bacteremia.

METHODS: The study was conducted at 500 bedded King Fahad Hospital and Tertiary Care Center, Al-Hofuf, Al-Hasa, Eastern Province of Saudi Arabia. Retrospectively infection control and microbiology records of patients having hospital acquired K. pneumoniae bacteremia during July 2001 to July 2003 were reviewed. Data on age, gender, location, onset of bacteremia, hospital stay after onset of bacteremia, prior antibiotic therapy, comorbid conditions and clinical outcome were recorded.

RESULTS: During 2 years of study period 26 patients developed hospital acquired K. pneumoniae bacteremia, out of them 10 patients had bacteremia due to ESBL producing strains. Extended-spectrum beta-lactamase producing K. pneumoniae bacteremia was significantly higher among patients of less than 65 years of age (p=0.004). Klebsiella pneumoniae bacteremia was more common (12/26, 46.1%) among diabetic patients and 8/12 had ESBL K. pneumoniae bacteremia. (p=0.02). Invasive devices (urinary and vascular catheters) were more commonly observed among patients having ESBL K.pneumoniae bacteremia (p=0.004, 0.001). Significantly higher number (9/10) of patients with ESBL K.pneumoniae bacteremia received prior third generation cephalosporins (p=0.001). Extended-spectrum beta-lactamase K. pneumoniae hospital acquired bacteremia had significantly longer hospital stay and higher mortality (p=0.0001).

CONCLUSION: Elderly age, diabetes, invasive devices and prior third generation cephalosporin therapy are the major risk factors for hospital acquired ESBL K.pneumoniae bacteremia, leading to significantly higher mortality and prolonged hospitalization. Infection control measures should be aggressively followed to prevent such infections among these high risk patients.