How to Read an Antibiogram

An antibiogram shows which antibiotics are effective against specific bacteria. This guide explains how to interpret resistance patterns and treatment options.

Understanding Key Terms

  • Susceptible (S): Bacteria respond well to antibiotic
  • Intermediate (I): May need higher doses or alternative treatment
  • Resistant (R): Antibiotic won't work effectively

Reading the Results

  1. Identify the bacterial species tested
  2. Check antibiotic names and their corresponding results
  3. Look for minimum inhibitory concentration (MIC) values when available
  4. Consider clinical relevance of intermediate results

Comparison of Testing Methods

Method Cost Time Required Accuracy
Disc diffusion Low 24 hours Good
Minimum inhibitory concentration Medium 24-48 hours High
Automated systems High 6-12 hours Excellent

Practical Application

  • Always consult with healthcare providers for treatment decisions
  • Consider patient factors like allergies and kidney function
  • Follow local guidelines for antibiotic use