Question 259

Question:

An otherwise healthy 55-year-old Asian American man is given isoniazid and vitamin B6 (pyridoxine) after conversion of his PPD skin test. An x-ray of the chest shows no abnormalities. Four weeks later, he develops abdominal pain and jaundice. Which of the following is the most likely explanation?

Correct Answer: C.  Isoniazid-induced hepatitis

Hepatotoxicity is a well known side effect of isoniazid. Pyridoxine is given with isoniazid to help prevent B6 deficiency and neurotoxicity. The proximity of this man’s symptoms to starting isoniazid, normal chest x-ray, and lack of exposure make tuberculosis and hepatitis B unlikely. Cholecystitis is not a well-known toxicity of pyridoxine and jaundice is not a typical feature of cholecystitis.