🦠 What is the Test?
The AFB (Acid-Fast Bacilli) Susceptibility Test for Streptomycin checks whether Mycobacterium tuberculosis (TB bacteria) is resistant or susceptible to the antibiotic streptomycin. This helps guide effective TB treatment.
📊 Normal Ranges:
Susceptible (S) → The bacteria respond to streptomycin (the drug is effective).
Resistant (R) → The bacteria do not respond to streptomycin (alternative treatments needed).
Intermediate (I) → Partial response; may require a higher dose or alternative therapy.
(Results are determined by laboratory testing.)
🎯 Purpose of the Test:
✅ Determines whether TB bacteria can be treated with streptomycin
✅ Helps in customizing TB treatment regimens
✅ Prevents antibiotic resistance by selecting the right medication
✅ Monitors drug resistance in TB patients who are not responding to treatment
🩺 When is it Recommended?
🔹 Diagnosed TB patients before starting treatment
🔹 Patients with recurrent or persistent TB
🔹 Those suspected of having drug-resistant TB
🔹 Individuals in high-risk groups, such as immunocompromised patients
📝 How is the Test Done?
A sample (sputum, tissue, or body fluid) is collected.
The bacteria are grown in a lab and tested for streptomycin resistance.
Results may take several weeks due to slow bacterial growth.
⚠️ What Do Abnormal Results Mean?
📉 Susceptible (S) → Streptomycin can be used to treat TB.
📈 Resistant (R) → Alternative antibiotics are needed to combat TB infection.