**Question:** The following are true about Acinetobacter except:

A. Acinetobacter is a Gram-negative bacterium that can cause infections in humans.
B. Acinetobacter is sensitive to most antibiotics, making treatment straightforward.
C. Acinetobacter is commonly found in soil and water, but can also infect humans.
D. Acinetobacter is a harmless commensal organism on human skin.

**Correct Answer:** B. Acinetobacter is sensitive to most antibiotics, making treatment straightforward.

**Core Concept:** Acinetobacter is a group of Gram-negative bacteria that can cause infections in humans. These infections are often found in healthcare settings, particularly in immunocompromised patients. Acinetobacter is known for its ability to adapt to various environments, including soil, water, and clinical settings, which contributes to its ability to cause infections.

**Why the Correct Answer is Right:** Acinetobacter is generally susceptible to a wide range of antibiotics, which is why treatment options are typically straightforward. However, the statement "most antibiotics" is incorrect, as some Acinetobacter strains may develop resistance to certain antibiotics. This resistance can be due to various mechanisms, including enzymatic inactivation, efflux pumps, and alteration of antibiotic targets.

**Why Each Wrong Option is Incorrect:**

A. Acinetobacter is a Gram-negative bacterium that can cause infections in humans, which is true.
C. Acinetobacter is commonly found in soil and water but can also infect humans, which is true.
D. Acinetobacter is a harmless commensal organism on human skin, which is false. Acinetobacter is typically found in the environment and can cause infections in humans. It is not a harmless commensal organism on human skin.

**Clinical Pearl:** Understanding Acinetobacter infections is crucial for healthcare professionals, as they can cause serious and often difficult-to-treat infections in immunocompromised patients. Early recognition, isolation precautions, and appropriate antibiotic therapy are essential for managing Acinetobacter infections.