WHO Recommendations for TB Diagnosis
1. Near Point-of-Care (NPOC) Molecular Tests
Definition:
Near point-of-care tests are rapid molecular diagnostic tests performed close to the patient, such as in primary health centers or peripheral laboratories.
Key Features
1. Detect Mycobacterium tuberculosis DNA using nucleic acid amplification tests (NAATs).
2. Provide results faster than traditional culture methods.
3. Can be used for initial diagnosis of TB.
Advantages
– Rapid diagnosis (minutes to hours).
– Can be used outside central laboratories.
– Helps early treatment initiation.
WHO recommends NPOC-NAATs on sputum samples as the initial diagnostic test instead of smear microscopy.
2. Tongue Swab Samples
Definition:
A tongue swab is a sample collected by gently swabbing the surface of the tongue to detect TB bacteria.
Why WHO recommends it
   -Useful when patients cannot produce sputum, such as:
    : Children
    : Elderly patients
    : People with HIV
    : Patients with mild symptoms
Advantages
> Non-invasive and easy to collect
> Can be self-collected or collected by trained personnel
> Expands access to TB testing
> WHO recommends NPOC molecular tests on tongue swabs when sputum cannot be obtained.
3. Sputum Pooling Strategy
Definition:
Sputum pooling involves mixing sputum samples from multiple individuals and testing them together using automated molecular tests.
Purpose
– Increase testing efficiency
– Reduce costs and resource use
Advantages
– Fewer tests needed for large populations
– Faster screening in resource-limited settings
– Helpful during high testing demand
– If a pooled sample tests positive, individual samples are then tested separately to identify the infected person.
