Table 2.
Overview of the most used methods to detect M. tuberculosis and its variants including cost-effectiveness
|
Assay |
Accessibility/cost |
Sensitivity |
Quantification |
Turnaround time* |
Resistance identification |
|---|---|---|---|---|---|
|
Bacilloscopy |
High |
Low |
Intermediate |
2–3 days |
No |
|
Solid culture |
Cheap |
Low |
Intermediate |
30–60 days |
No |
|
Liquid culture |
Intermediate |
Intermediate |
Intermediate |
15–30 days |
No |
|
Flow cytometry |
Low |
High |
High |
2–3 days |
Yes |
|
Nested PCR/RT-PCR |
Low |
Intermediate |
Low |
2–4 days |
Yes |
|
qRT-PCR |
Low |
Low |
Intermediate |
2–4 days |
No† |
|
GeneXpert MTB/RIF |
Low |
High |
High |
90 min |
Yes |
|
Fluorescence microscopy |
Intermediate |
High |
High |
1–2 days |
Yes |
*Time to detect the presence or absence of M. tuberculosis, according to the Foundation for Innovative New Diagnostics (FIND).
†Except for EP-TB [92].