Finally, a comparative study of 166 patients with blood eosinophilia (>1.000 cells/μL) and systemic manifestations demonstrated that CRP level was a sound diagnostic biomarker that could accurately differentiate between HES and EGPA, with low levels (<36 mg/L) suggestive of HES (175). Here, CRP is linked to eosinophilic granulomatosis with polyangiitis.