Sputum smear microscopy in the Xpert^® MTB/RIF era

Area of Science:

• Medical Diagnostics
• Infectious Diseases
• Public Health

Background:

• Pulmonary tuberculosis (TB) diagnosis relies on various methods, including microscopy and molecular assays.
• The Xpert MTB/RIF assay represents a recent advancement, while acid-fast bacilli microscopy is an established technique.

Purpose of the Study:

• To provide a balanced perspective on the assessment and application of both microscopy and Xpert MTB/RIF for TB diagnosis.
• To identify challenges hindering the use of these diagnostic methods in TB control programs.

Main Methods:

• Comparative analysis of the merits and shortcomings of microscopy and Xpert MTB/RIF assay.
• Discussion of factors impacting the utility of these diagnostic tools in real-world settings.

Main Results:

• Neither microscopy nor Xpert MTB/RIF alone provides complete diagnostic information for TB.
• Systematic replacement of microscopy by Xpert is not feasible in the near future; complementarity is key.
• Advancements in microscopy were previously hampered by issues with decentralized culture-based testing.

Conclusions:

• Microscopy and Xpert MTB/RIF should be used complementarily to ensure comprehensive, accessible TB diagnostic services.
• This integrated approach targets high-risk individuals and optimizes TB control strategies.
• Future applications of microscopy and Xpert are expected to reduce reliance on culture-based methods.