CRP and chronic obstructive pulmonary disease: In COPD patients from the Melbourne Longitudinal COPD Cohort (an open cohort of participants with moderate to severe COPD GOLD stages II–IV), both SAA and C-reactive protein (CRP) were elevated at the exacerbation onset compared with stable disease while SAA was a more sensitive and specific inflammatory biomarker compared to CRP during exacerbations [76].