This condition is an inflammation of bone usually resulting from a bacterial infection.

The condition described as an inflammation of bone that usually results from a bacterial infection is osteomyelitis. This condition specifically involves the bone itself and can occur when bacteria enter the bone tissue, often through an open wound, or it can spread from nearby tissues or through the bloodstream. Symptoms typically include pain in the affected area, fever, and sometimes swelling or redness over the bone.

Arthritis primarily refers to inflammation of the joints, not the bones directly. Nephritis involves inflammation of the kidneys, while dermatitis is related to skin inflammation. Each of these conditions affects different parts of the body and has distinct causes and symptom profiles, which helps clarify why osteomyelitis is the correct answer to the question.