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Lung Disease & Respiratory Health Center

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Nasal Potential Difference Test for Cystic Fibrosis - Topic Overview

The nasal potential difference test (nasal PD test) measures how well salts (sodium and chloride) flow across the mucous membranes in the nose. This type of test can be helpful when the results of a sweat test or a genetic test are not clear.

In this test, electrodes are placed inside the nose and liquids are run through the nose. There is also a needle placed in the forearm that connects to a machine. Because this test can be uncomfortable, your child may need medicine to help him or her relax before having the test.

Recommended Related to Lung Disease/Respiratory Problems

Pleural Effusion

A pleural effusion is an abnormal amount of fluid around the lung. Pleural effusions can result from many medical conditions. Most pleural effusions are not serious by themselves, but some require treatment to avoid problems.

Read the Pleural Effusion article > >

This test is not used very often because it can be difficult to do and because it is not available in many places.

    WebMD Medical Reference from Healthwise

    Last Updated: September 09, 2014
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
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