Pleural Fluid and Serum Procalcitonin in Patients With Parapneumonic Pleural Effusion
Condition: Community Acquired Pneumonia
MeSH terms: Pneumonia; Pleural Effusion
Study type: Observational

Summary: 
      Key words : serum, pleural effusion, procalcitonin, pneumonia Pneumonia is the common cause
      of pleural effusion (ranged 2nd) and bacterial infection is the main etiology of pneumonia.
      Procalcitonin, the prohormone of calcitonin, is a 116 amino-acid protein produced by C-cell
      of the thyroid gland. During severe infection, procalcitonin is probably produced by
      extra-thyroid tissues and the concentration increased rapidly in bacterial infection but
      remains low in viral infections. However, the exact origin and pathophysiological role of
      procalcitonin during sepsis is not clear and it is not a marker of infection as such, since
      localized infections or infections with no systemic manifestation cause a little if any
      increase in procalcitonin levels. This study will focus on assessing the value of
      procalcitonin in pleural effusion for diagnosis, severity and prognosis among
      community-acquired pneumonia with pleural effusion, such as in serum. 100 patients with
      clinical pneumonia infection score over six points diagnosed of community-acquired pneumonia
      and proved to have pleural effusion by chest sonography on admission will be studied
      prospectively. Serum and effusion procalcitonin levels will be measured initially and 3 days
      later after medical therapy. Bacterial pneumonia will be identified if bacteria was cultured
      from any one of the three kinds of specimen, including blood, pleural effusion or
      bronchoalveolar lavage. Then we will divide one hundred of patients into bacterial or
      non-bacterial groups. Finally, we will analyze demographic and procalcitonin data of serum
      and pleural effusion between these two groups and compare the difference between the severe
      or mild and response or non-response bacterial community-acquired pneumonia statistically.

      The aim of the study will be to verify whether procalcitonin levels measured in the serum and
      pleural effusion could serve as a predictor for bacterial community-acquired pneumonia with
      pleural effusion and the different levels will also be indicative of severity and prognosis.
      We hope that the predictor from pleural effusion will be more sensitive or specific than that
      from serum and could be detectable in localized bacterial infection.
    

Detailed description: 
      In this study, the first goal will be to determine the sensitivity, specificity, and
      predictive value of serum and pleural effusion PCT level in CAP with pleural effusion. The
      second goal will be to decide an appropriate value in serum or pleural effusion to assess as
      an index of severity and prognosis in bacterial CAP with pleural effusion.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Patients from the out-patient-department in division of pulmonary and critical care
        medicine and the department of emergency medicine at Chang Gung Memorial Hospital,
        Kaohsiung.
      
Biospecimen description: 
      serum,pleural fluid
    
Keywords: serum, pleural effusion, procalcitonin, pneumonia