A patient returns to the clinic after a regimen of antibiotics for a wound that is not healing. The provider is unsure of the type of organism infecting the wound. Which diagnostic would the nurse expect to perform in this scenario?

A. Complete blood count: A CBC can indicate infection through elevated white blood cell count, but it does not identify the specific organism or determine which antibiotic is effective. It provides general information rather than targeted guidance. B. Urinalysis: A urinalysis evaluates urinary tract function and infections, not wound infections. It is unrelated to identifying the pathogen in a non-healing wound. C. X-ray of the wound: An X-ray can assess for bone involvement or foreign bodies but does not identify the causative microorganism or guide antibiotic selection. Imaging is supportive, not diagnostic for pathogen type. D. Wound culture and sensitivity: A wound culture identifies the specific organism causing the infection, and sensitivity testing determines which antibiotics will effectively treat it. This diagnostic is essential when a wound is not healing and the causative pathogen is unknown.