Is procalcitonin elevation always an indicator of bacterial infection?

Adult-onset Still’s disease is a systemic inflammatory disorder with fever, arthritis, and rash.[1] Although the etiology is not known, some viral (rubella, echovirus, Epstein-Barr, cytomegalovirus) and bacterial (Yersinia enterocolitica, Mycoplasma pneumoniae) factors have been accused.[2] It is difficult to diagnose and can be diagnosed by excluding other causes, such as malignancy, collagen tissue disease, and infection. It is very difficult to distinguish from bacterial infections, especially since it is accompanied by fever and rashes, elevated C-reactive protein (CRP), erythrocyte sedimentation rate, and leukocytosis.