How is the presence of infection confirmed in osteomyelitis?

In osteomyelitis, the confirmation of infection is primarily achieved through positive wound cultures. When a wound is present or if there is drainage from the site of infection, obtaining cultures can help isolate the organism responsible for the infection, which is critical for diagnosis and determining appropriate treatment.

Wound cultures can reveal specific pathogens, allowing for targeted antibiotic therapy, which is especially important in osteomyelitis because infections may involve resistant strains of bacteria. Unlike the other options, which provide indirect evidence or a lack of evidence for infection, positive cultures give a direct indication of an infectious organism in the area.

Radiographic findings can suggest changes consistent with osteomyelitis, such as bone destruction or abscess formation, but they do not confirm the presence of infection. Similarly, negative blood tests or normal ESR test results can indicate that there may not be significant systemic inflammation or infection, but they do not rule out osteomyelitis, and low inflammation markers can sometimes be seen in chronic cases. Thus, while imaging and blood tests may support the diagnosis, they are not definitive for confirming infection in osteomyelitis.