Relationship between serum procalcitonin level and chronic obstructive pulmonary disease

Background: Differentiation of the etiologies of acute exacerbations of chronic obstructive pulmonary disease (AECOPD) and differential diagnosis of other causes of respiratory attacks in chronic obstructive pulmonary disease (COPD) patients are challenging. Serum procalcitonin (PCT) which is a biomarker of bacterial infection, but not viral infections, could possibly recognize AECOPD requiring antibiotic treatment from other etiologies of respiratory attack. Methods: Patients aged from 40-80 years who were diagnosed with COPD according to the GOLD criteria and who referred to the Imam Khomeini Hospital of Ahvaz in 2016 were divided into two groups of exacerbated and stable COPD. Exacerbation of COPD is defined as worsening of the patient's condition from the stable state and behind normal day-to-day variations that is acute in onset and may necessitate treatment in a patient with underlying COPD. BODE Index and 6MWDT were used to assess the patients, and the severity of their disease was determined based on the GOLD criteria. Subsequently, PCT testing using electrochemiluminescence (ECL) method was carried out on patients on the same day. Results: PCT level in the exacerbation group was 0.272 +/- 0.586 and 0.066 +/- 0.027 in the non-exacerbation group, and their difference was statistically significant with P value = 0.001. Based on the results, the cut point of differentiating between the AECOPD and the stable groups with a sensitivity of 68% and a specificity of 80% is 0.085. Conclusion: Overall, the findings of this study indicate that PCT levels could be regarded as a good diagnostic marker for patients with COPD, and for the differentiation of AECOPD patients from stable COPD patients.