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What's the difference between a positive and negative PPD test?

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Dr. Gutti Rao
Internal Medicine - Hospital-based practice

In brief: PPD

Positive test: 5mm in HIV patients and other immunosuppressed individuals all others: 10 mm .
Measured induration after 48 hours. Negative reaction: not exposed to tb.

In brief: PPD

Positive test: 5mm in HIV patients and other immunosuppressed individuals all others: 10 mm .
Measured induration after 48 hours. Negative reaction: not exposed to tb.
Dr. Gutti Rao
Dr. Gutti Rao
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