Histopathological Techniques and PCR on Tissues Included in Paraffin for the Diagnosis of Tuberculosis

Evaluation of the Sensitivity of Histopathological Techniques and Molecular Biology (PCR) on Tissues Fixed in Paraformaldehyde and Included in Paraffin for the Diagnosis of Tuberculosis in Current Practice

Tuberculosis (TB) remains a major public health problem nowadays. About 30% of the world population is infected with Mycobacterium tuberculosis. There is an increase in the number of cases of classic tuberculosis in developing countries, even if number of cases are declining in developed countries. However, in developed countries this decrease is counterbalanced by the emergence of multidrug resistant (MDR) strains of the bacteria.

There are also latent forms (1/3 of the world population) of the infection that can be reactivated in one case out of ten. Each year, about 2 million people die of tuberculosis and 9 million new cases are identified, including about 500,000 cases of MDR TB.

The spread of this disease as well as the increasing number of cases of MDR tuberculosis, reinforce the need for research and development of strategies of diagnosis and management of this affection.

Nowadays, the culture is the gold standard for the TB diagnosis but this technique needs at least three weeks to be performed. The objective of this study is to evaluate the sensitivity and specificity of histopathological and molecular techniques (PCR) on paraformaldehyde fixed and embedded in paraffin tissues for a faster diagnosis of tuberculosis in current practice, in order to administrate an efficient treatment as soon as possible.

Inclusion Criteria:

• Positive TB patients
• Patients who performed biopsy before inclusion

Exclusion Criteria:

• Anti-tuberculosis drugs administered before biopsy
• Patients who refuse to participate