Mycobacterium Tuberculosis – Part 5 – Gelification test for Tuberculosis (Glutaraldehyde gelification test)

Sample

1. This test is done in the serum.
2. EDTA blood can be used.

Indication

1. For the diagnosis of pulmonary tuberculosis as a screening test.
2. This is a simple, rapid, and inexpensive screening test.

Pathophysiology of Tuberculosis

1. Tuberculosis is a chronic and debilitating disease.
2. This is seen in two forms:
   1. Primary tuberculosis. This will give the primary complex.
   2. Secondary or post-primary tuberculosis. Involve the lung with the most common site of apices of the lung.

Signs and Symptoms

Signs and symptoms are summarized below.

Procedure

1. EDTA-blood and 2.5% glutaraldehyde solution were mixed,
2. A shorter gelification time was observed in blood from patients with pulmonary tuberculosis.
3. This test advised in clinically suspected cases of tuberculosis where X-Ray chest and clinical history favor the diagnosis of Pulmonary tuberculosis.
4. This test is helpful in Sputum AFB negative cases.

Result

1. Shorter time in pulmonary tuberculosis than the non-tuberculous patients.
2. The glutaraldehyde test gives a sensitivity of 89% and a specificity of 95%.
3. In one of the study was found:
   1. For pulmonary TB sensitivity was 96.6% and specificity 82.1%.
   2. For extrapulmonary TB sensitivity was 91.2% and specificity 77.4%.

Advantage

1. In case if there is no facility for the TB culture and state of the art radiology. Then this method along with Sputum for AFB and simple X-Ray is cost-effective and reliable.
2. There is no need for any sophisticated instrument.

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