Sputum Culture & Sensitivity Test

The Sputum Culture and Sensitivity (C&S) test is used to detect bacterial, fungal, or mycobacterial infections in the lungs and to determine the most effective antibiotics for treatment. It is commonly used to diagnose pneumonia, tuberculosis (TB), bronchitis, and lung abscesses.

Why is the Test Done?

A doctor may order this test if a patient has:
✅ Persistent cough with mucus (lasting more than 2 weeks)
✅ Fever, chills, and difficulty breathing
✅ Blood in sputum (hemoptysis)
✅ Suspected pneumonia, tuberculosis (TB), or other lung infections
✅ To check antibiotic resistance in respiratory infections

What Does the Test Detect?

This test identifies bacterial or fungal pathogens in sputum. Common pathogens include:

How is the Test Done?

1. Sample Collection:

• The patient is asked to cough deeply and collect morning sputum in a sterile container.
• Avoid contamination with saliva or nasal secretions.
• The sample is sent to the lab immediately.

2. Laboratory Process:

1. Culture: The sputum is placed on a special growth medium and incubated for 24–72 hours.
2. Bacterial/Fungal Identification: Growth is analyzed under a microscope.
3. Antibiotic Sensitivity Testing (AST):
   • The bacteria are tested against different antibiotics to find the most effective treatment.
   • Helps guide appropriate antibiotic therapy and avoid resistance.

Test Results Interpretation

🔬 If Pathogens Are Found:

• Antibiotic Sensitivity Report will indicate which antibiotics are effective.
• Resistant Bacteria: If the bacteria are resistant to multiple antibiotics, special drugs may be needed.

Next Steps After a Positive Result

💊 Targeted Antibiotic Therapy (based on sensitivity results)
😷 Isolation in contagious infections (e.g., TB, MDR bacteria)
🌬️ Supportive care (nebulization, oxygen therapy if needed)