On the basis of the data retrieved by literature search, we construct a diagnostic algorithm useful to examine the patients with postoperative fever after arthroplasty and able to distinguish infectious from noninfectious fever.

We suggest that the presence of fever prompts an accurate clinical examination and laboratory investigation.

In our diagnostic algorithm, continuous fever persisting during the second and third day after arthroplasty can represent indication to dosage of serum procalcitonin and IL-6 (if the dosage is available).

If procalcitonin dosage is elevated, blood culture and other microbiological investigations can be performed on the basis of clinical findings. In fact, the presence of associated symptoms has to guide the choice of subsequent investigation, such as chest X-ray in the presence of pulmonary symptoms or culture of urine in the presence of urinary tract symptoms. Also the surgical site has to be the object of an accurate clinical evaluation for the presence of swelling, warmth and drainage. Culture from an infected surgical site has to be immediately attempted.

Timely administration of adequate antibiotic therapy is an important factor to reduce morbidity and mortality in patients with postoperative infections, and thus a thorough clinical examination and diagnostic algorithm is mandatory.

Antibiotic therapy must be started only in the presence of diagnosis of bacterial infections (Fig. 24.1).