Mycobacterium haemophilum growth requirements include the need for which of the following?

• A. Requires high CO2
• B. No special requirements
• C. Ferric ammonium citrate or hemin required
• D. Glucose needed

Answer: (C)

Certain mycobacteria are fastidious and need specific nutrients beyond what routine media provide. Mycobacterium haemophilum is one of these; it requires an iron source to grow. In the lab, growth only occurs when the medium includes iron, supplied as ferric ammonium citrate or hemin. Without this iron enrichment, the organism will not grow well or at all, which is why iron supplementation is a defining growth requirement.

The other options don’t reflect what this species needs: it does not inherently require high CO2, it certainly does have a special requirement (iron), and glucose is not the driving nutrient for its growth.