Which antibiotic must not be given if the organism causing pneumonia yields a positive Modified Hodge test?

Which antibiotic must not be given if the organism causing pneumonia yields a positive Modified Hodge test?

• A. Imipenem
• B. Tobramycin
• C. Gentamycin
• D. Tetracycline

Answer: (A)

A positive Modified Hodge test signals carbapenemase production, meaning the organism can inactivate carbapenem antibiotics. Since imipenem is a carbapenem, administering it would be ineffective against a carbapenemase-producing organism, so it must not be used. Other drugs on the list aren’t ruled out by this test alone; their effectiveness depends on specific susceptibility for that organism, but the key takeaway is that carbapenems should be avoided when carbapenemase production is present.

A positive Modified Hodge test signals carbapenemase production, meaning the organism can inactivate carbapenem antibiotics. Since imipenem is a carbapenem, administering it would be ineffective against a carbapenemase-producing organism, so it must not be used. Other drugs on the list aren’t ruled out by this test alone; their effectiveness depends on specific susceptibility for that organism, but the key takeaway is that carbapenems should be avoided when carbapenemase production is present.