You'll need to have a skin test for tuberculosis, a chest X-ray and a test for hepatitis B before taking infliximab.

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For instance, a new diagnostic test for tuberculosis is about to become more affordable and accessible in the developing world, causing diagnostics to leapfrog more than a century.

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He also advises asking for proof of a tuberculosis screening within the past year, as well as a recent test for community-associated Methicillin-resistant Staphylococcus aureus (CA-MRSA), which can be transmitted by skin-to-skin contact and cause painful skin infections and boils.

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