A Mantoux skin test shows 7 mm induration. What action should the practical nurse take?

A Mantoux skin test shows 7 mm induration. What action should the practical nurse take?

• A. No action is required, as this is a normal finding.
• B. Repeat the test, as inconclusive.
• C. Refer to physician for further investigation.
• D. Prophylactic medications that will be ordered by physician.

Answer: (C)

Mantoux interpretation hinges on risk factors and exposure, not just the number of millimeters. A 7 mm induration is not automatically considered positive for everyone; thresholds vary by risk group, so without knowing the patient’s risk factors or symptoms, the result cannot be acted on alone. The appropriate nursing action is to refer the patient for physician evaluation to determine whether further testing (such as a chest X-ray or sputum studies) or treatment for latent TB infection is indicated. The physician will interpret the result in the full clinical context and decide the next steps.

Mantoux interpretation hinges on risk factors and exposure, not just the number of millimeters. A 7 mm induration is not automatically considered positive for everyone; thresholds vary by risk group, so without knowing the patient’s risk factors or symptoms, the result cannot be acted on alone. The appropriate nursing action is to refer the patient for physician evaluation to determine whether further testing (such as a chest X-ray or sputum studies) or treatment for latent TB infection is indicated. The physician will interpret the result in the full clinical context and decide the next steps.