Tuberculosis (TB)

Fluorescent light-emitting diode (LED) microscopy for diagnosis of tuberculosis policy

Policy statement

World Health Organization

Publication details

Number of pages: 16
Publication date: 2011
Languages: English
ISBN: 9789241501613
WHO reference number: WHO/HTM/TB/2011.8



Light-emitting diodes (LED) have been developed to offer the benefits of fluorescence microscopy without the associated costs. In 2009, the evidence for the efficacy of LED microscopy was assessed by the World Health Organization, on the basis of standards appropriate for evaluating both the accuracy and the effect of new TB diagnostics on patients and public health.

The results showed that the accuracy of LED microscopy was equivalent to that of international reference standards, it was more sensitive than conventional Ziehl-Neelsen microscopy and it had qualitative, operational and cost advantages over both conventional fluorescence and Ziehl-Neelsen microscopy.

On the basis of these findings, WHO recommends that conventional fluorescence microscopy be replaced by LED microscopy, and that LED microscopy be phased in as an alternative for conventional Ziehl-Neelsen light microscopy.