Factors associated with airway colonisation and invasion due to Klebsiella spp

Area of Science:

• Medical Microbiology
• Infectious Diseases
• Pulmonary Medicine

Background:

• Klebsiella species are significant pathogens in respiratory infections.
• Understanding the clinical implications of heavy sputum growth is crucial for patient management.

Purpose of the Study:

• To investigate the clinical significance of heavy Klebsiella spp. growth in sputum.
• To identify risk factors for colonization and invasive disease.
• To evaluate the utility of sputum Gram stain for diagnosing invasive Klebsiella infections.

Main Methods:

• Retrospective study of 54 patients with heavy Klebsiella spp. growth in sputum.
• Analysis of patient demographics, clinical history, and microbiological data.
• Assessment of risk factors for colonization and invasive disease.

Main Results:

• Most patients (51/54) had factors predisposing to respiratory colonization or invasion.
• Risk factors for colonization and invasive disease were similar.
• Community-acquired Klebsiella infections were associated with chronic respiratory diseases.
• Prior antibiotic use was a risk factor for nosocomial infections, often with resistant strains.
• Common diagnoses included airway colonization, community-acquired, and nosocomial chest infections; primary pneumonia was rare.
• Sputum Gram stain sensitivity and specificity for invasive disease were 42% and 69%.

Conclusions:

• Heavy Klebsiella spp. sputum growth is frequently associated with underlying risk factors and diverse clinical presentations.
• Risk factor profiles for colonization and invasive disease overlap.
• Antibiotic resistance is a concern in nosocomial Klebsiella infections.
• Sputum Gram stain has limited accuracy in predicting invasive Klebsiella disease.