The Mantoux reaction in pulmonary tuberculosis

Area of Science:

• Medical Diagnostics
• Infectious Diseases
• Pulmonology

Background:

• Tuberculosis diagnosis relies on various methods, including sputum microscopy and immunological tests.
• The Mantoux test (tuberculin skin test) is a common tool for assessing cell-mediated immunity to Mycobacterium tuberculosis.
• Accurate interpretation of Mantoux test results is crucial, especially in differentiating active disease from latent infection or other conditions.

Purpose of the Study:

• To evaluate the efficacy of the Mantoux test in diagnosing active tuberculosis.
• To correlate Mantoux test induration sizes with sputum positivity in tuberculous patients.
• To assess the performance of the Mantoux test in sputum-negative individuals.

Main Methods:

• The Mantoux tuberculin skin test was administered to 181 patients diagnosed with tuberculosis.
• Patient sputum was examined for the presence of acid-fast bacilli (sputum-positive vs. sputum-negative).
• Tuberculin reaction induration sizes were measured and categorized.

Main Results:

• In 124 sputum-positive cases, 93% showed Mantoux reactions between 10 and 19 mm.
• Only 2 sputum-positive cases had reactions less than 6 mm.
• Among sputum-negative cases, 12% were Mantoux negative, and 9% had reactions less than 10 mm.

Conclusions:

• The Mantoux test demonstrates high sensitivity in sputum-positive tuberculosis patients, with typical reactions between 10-19 mm.
• A significant proportion of sputum-negative cases showed minimal or negative Mantoux reactions, indicating potential diagnostic ambiguity.
• The findings suggest the Mantoux test is a valuable adjunct but may require careful interpretation alongside other diagnostic data, particularly in sputum-negative individuals.